Charging / discharging circuit, system, and control method thereof

Abstract

The embodiments of the present application provide a charging / discharging circuit, a system and a control method thereof, comprising a power supply module, a heating module and a charging / discharging switching module, the power supply module comprises at least a first assembled battery, the heating module comprises an energy storage module and a switch module, the at least first assembled battery, the switch module and the charging / discharging switching module are connected in parallel, a first end of the energy storage module is connected to the switch module, and a second end of the energy storage module is connected to the charging / discharging switching module, the charging / discharging switching module and the switch module are used to generate an AC waveform current in the charging / discharging circuit in response to a charging / discharging enable signal. The present application forms a discharging circuit and a charging circuit that alternate in the charging / discharging circuit by controlling the on or off of the switch module and the charging / discharging switching module, thereby forming an AC current in the charging / discharging circuit, the AC current flows through the assembled battery, the internal resistance of the assembled battery generates heat, and the effect of heating the assembled battery is achieved.

Description

[Technical Field]

[0001] The present application relates to the field of battery technology, and in particular to a charging and discharging circuit, a system and a control method thereof. [Background technology]

[0002] Due to their advantages such as high energy density, cyclic charging, safety and environmental friendliness, power batteries are widely used in fields such as new energy vehicles, consumer electronics and energy storage systems.

[0003] However, the use of power batteries in low-temperature environments has certain limitations, such as a significant drop in the discharge capacity of the power battery and the inability to charge the battery in low-temperature environments, so that the power battery needs to be heated in low-temperature environments to ensure normal use.

[0004] The conventional power battery heating technology may cause the problem of excessive motor vibration noise in the process of using a motor circuit to heat the power battery. Summary of the Invention

[0005] The embodiments of the present application provide a charging / discharging circuit, system, and control method thereof that can realize heating of a power battery and effectively suppress motor vibration noise when heating the battery using a motor circuit.

[0006] According to a first aspect, there is provided a charge / discharge circuit, the charge / discharge circuit including a power supply module, a heating module, and a charge / discharge switching module; the power supply module includes at least a first assembled battery; the heating module includes an energy storage module and a switch module; the at least first assembled battery, the switch module, and the charge / discharge switching module are connected in parallel; a first end of the energy storage module is connected to the switch module, and a second end of the energy storage module is connected to the charge / discharge switching module; The charge / discharge switching module and the switch module are used to generate an AC waveform current in the charge / discharge circuit in response to a charge / discharge enable signal.

[0007] In the charge / discharge circuit, the charge / discharge switching module and the switch module are controlled to form an alternating charge circuit and a discharge circuit between at least a first assembled battery included in the power supply module and the energy storage module, and in the process of alternating between the charge circuit and the discharge circuit, an AC waveform current is generated in the charge / discharge circuit, and this AC waveform current flows through at least the first assembled battery included in the power supply module, causing the internal resistance of the batteries in at least the first assembled battery to generate heat, thereby achieving the effect of heating the assembled battery included in the power supply module.

[0008] The charging and discharging circuit can heat the battery without using the electric vehicle's motor, and the motor is not affected by the frequency of the current in the charging and discharging circuit during the battery heating process, solving the conventional technical problem of large motor vibration noise during the power battery heating process. When the charging and discharging circuit is used to heat the battery, the motor can drive the power vehicle normally, thereby achieving heating while driving.

[0009] In one implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit connected in series; a connection point between the first switching circuit and the second switching circuit is connected to a second end of the energy storage module; The first switching circuit and the second switching circuit are used to be turned on or off by the trigger of the charge / discharge enable signal.

[0010] In this implementation, the charge / discharge switching module includes two switching circuits, which are used to control the charge / discharge circuit to form a charge circuit or a discharge circuit. Specifically, the first switching circuit, the second switching circuit, and the switch module are controlled to turn on or off to form an alternating charge circuit and a discharge circuit between the power supply module and the energy storage module, generating an AC waveform current in the charge / discharge circuit, thereby realizing the effect of heating the battery pack included in the power supply module.

[0011] The connection point between the first switching circuit and the second switching circuit is connected to the second end of the energy storage module, and the first end of the energy storage module is connected to the switch module. In this way, by rationally controlling the switch module, the first switching circuit, and the second switching circuit, it is possible to realize alternating charging and discharging between the power supply module and the energy storage module, thereby causing the internal resistance of the battery pack in the power supply module to heat up and achieving the effect of self-heating from within the battery pack. Heating from within the battery pack results in higher heating efficiency.

[0012] In one implementation, the first switching circuit includes a first upper arm, and the second switching circuit includes a first lower arm; a connection point between the first upper arm and the first lower arm is connected to a second end of the energy storage module; The first upper arm and the first lower arm are used to be turned on or off by the trigger of the charge / discharge enable signal.

[0013] By controlling the on / off of the first upper arm, the first lower arm, and the switch module, an AC waveform current is generated in the charge / discharge circuit, thereby achieving the effect of heating the battery pack included in the power supply module.

[0014] In one implementation, the first upper arm includes a first switch and a first diode connected in parallel, and the first lower arm includes a second switch and a second diode connected in parallel; The cathode of the first diode is connected to the positive electrode of the first assembled battery, the anode of the first diode is connected to the cathode of the second diode, and the anode of the second diode is connected to the negative electrode of the first assembled battery.

[0015] The first and second diodes may be freewheeling diodes, which are typically used in conjunction with inductors. A sudden change in inductor current can cause a sudden change in the voltage across the inductor, potentially damaging other circuit elements. However, when used in conjunction with freewheeling diodes, the inductor current changes more gently, avoiding sudden voltage changes and improving circuit safety. Therefore, the first upper arm and the first lower arm each employ a parallel-connected switch and freewheeling diode structure to achieve a switching function, and the on / off switching of the switches in the first upper arm and the first lower arm can be controlled to switch between the charging circuit and the discharging circuit. The freewheeling diodes in the first upper arm and the first lower arm can avoid sudden voltage changes and improve the safety of the entire charging and discharging circuit.

[0016] Furthermore, in a structure in which the first upper arm and the first lower arm both include the above-mentioned switches and diodes connected in parallel, the charge / discharge switching module can have more combination control methods in terms of controlling the on / off of the circuit, and the control is more flexible and varied. By rationally controlling the on / off of different devices, it is possible to form a charge circuit or a discharge circuit in the charge / discharge circuit, balance the operating frequencies of different devices, and improve the service life of each device included in the charge / discharge switching module.

[0017] In one implementation, the first upper arm includes a third switch, and the first lower arm includes a fourth switch.

[0018] The first upper arm and the first lower arm only include switches, which allow the charge / discharge switching module to more easily control the on / off of the circuit to form a charge circuit or a discharge circuit in the charge / discharge circuit, thereby realizing heating of the battery pack and reducing the cost of the charge / discharge circuit.

[0019] In one implementation, the first switching circuit includes a third diode, and the second switching circuit includes a fifth switch; The cathode of the third diode is connected to the positive electrode of the first assembled battery, the anode of the third diode is connected to one end of the fifth switch, and the other end of the fifth switch is connected to the negative electrode of the first assembled battery.

[0020] The charge / discharge switching module uses one diode and one switch connected in series, which reduces the cost by half compared to using two switch tubes and saves the cost of switching period.In addition, the diode is passively controlled and does not require active control, so the control policy of the structure using one diode and one switch is simpler.

[0021] In one implementation, the first switching circuit further includes a sixth switch, one end of the sixth switch being connected to the positive electrode of the first assembled battery, and the other end of the sixth switch being connected to the negative electrode of the third diode.

[0022] The sixth switch is installed to prevent current from flowing through the third diode in scenarios where heating of the battery is not required, thereby preventing circuit failure due to current flowing through the third diode in scenarios where heating is not required, and improving the service life of electrical devices in the circuit.

[0023] In one implementation, the first switching circuit includes a seventh switch, and the second switching circuit includes a fourth diode; One end of the seventh switch is connected to the positive electrode of the first assembled battery, the other end of the seventh switch is connected to the cathode of the fourth diode, and the anode of the fourth diode is connected to the negative electrode of the first assembled battery.

[0024] In this implementation, the charge / discharge switching module uses one diode and one switch connected in series, which reduces the cost by half compared to using two switch tubes and saves the cost of the switching period.The diode is passively controlled, does not require active control, and the control policy is simpler.For example, this charge / discharge switching module can flexibly switch between the charge circuit and the discharge circuit in the charge / discharge circuit, thereby forming an AC current in the charge / discharge circuit.

[0025] In one implementation, the second switching circuit further includes an eighth switch; The eighth switch is connected in series between the fourth diode and the negative electrode of the first assembled battery.

[0026] The eighth switch is installed to prevent current from flowing through the fourth diode in scenarios where heating of the battery is not required, thereby preventing circuit failure due to current flowing through the fourth diode in scenarios where heating is not required, and improving the service life of electrical devices in the circuit.

[0027] In one implementation, the energy storage module includes a first energy storage element, the first energy storage element including at least one inductor, a first end of the first energy storage element connected to the switch module, and a second end of the first energy storage element connected to the charge / discharge switching module.

[0028] In this implementation, the energy storage module may include only a first energy storage element, which may include one or more inductors. By installing the first energy storage element, the electrical energy released by the power supply module when the charging / discharging circuit is set to a discharging circuit may be stored in the first energy storage element. When the charging / discharging circuit is switched to a charging circuit, the first energy storage element recharges the power supply module with its stored electrical energy, causing AC current to flow through the power supply module, which heats the internal resistance of the battery pack in the power supply module and achieves the effect of internal heating of the battery pack. Compared to external heating of the battery pack, the self-heating method of internally heating the battery pack provides a superior heating effect.

[0029] In one implementation, the energy storage module further includes a second energy storage element, and the second energy storage element is connected between a second end of the first energy storage element and the charge / discharge switching module.

[0030] A second energy storage element is added between the first energy storage element and the charge / discharge switching module, and the first energy storage element is connected in series with the second energy storage element. When a discharge circuit is formed in the charge / discharge circuit, the electrical energy released by the power supply module can be jointly stored by the first energy storage element and the second energy storage element, thereby enabling more energy storage. When the charge / discharge circuit is switched to a charge circuit, the first energy storage element and the second energy storage element recharge the stored electrical energy into the battery pack of the power supply module. This larger electrical energy during charging and discharging allows a larger charging / discharging current to be generated in the charge / discharge circuit. The larger the current, the more heat is generated due to the internal resistance of the battery as it flows through the battery pack. This improves the rate at which the battery pack temperature rises, improves the efficiency of battery self-heating, and allows the battery pack temperature to rise to the desired temperature as quickly as possible. Furthermore, the greater the charging / discharging energy, the more the current and frequency parameters in the battery self-heating process can be optimized, enhancing the self-heating effect of the battery.

[0031] In one implementation, the second energy storage element includes at least one inductor and / or capacitor, and can be implemented by electrical devices with various energy storage functions, allowing for more variations in the circuit structure of the charging and discharging circuit to meet different user or industrial production needs for the charging and discharging circuit structure.

[0032] In one implementation, a ninth switch is connected between the energy storage module and the charge / discharge switching module, and the ninth switch is connected in series with the second energy storage element.

[0033] The ninth switch is used to provide protection for the normal operation of components such as the energy storage module, the second energy storage element, and the switch module. When the first switching circuit and / or the second switching circuit fails in heating mode and a breakdown or short circuit occurs, it is necessary to ensure that the connection between the disconnected energy storage module, the second energy storage element, and the power supply module is cut off to avoid a situation in which the energy storage module, the second energy storage element, and the power supply module are short-circuited. By controlling the ninth switch to be cut off, the risk of a short circuit that exists in such a case can be effectively avoided.

[0034] In one implementation, the switch module includes at least one set of switch arms, and the first energy storage element in the energy storage module includes at least one energy storage device, the number of the energy storage devices is equal to the number of the switch arms, and the energy storage devices are connected in one-to-one correspondence with the switch arms; The connection point of the second end of each of the energy storage devices is connected to the charge / discharge switching module.

[0035] In this implementation, the switch module includes at least one pair of switch arms, and the switch arms have a symmetrical structure. By controlling the on / off of each pair of switch arms and the charge / discharge switching module, a charging circuit and a discharging circuit are formed, which are alternately switched in the charging / discharging circuit, thereby charge / discharge circuitThis generates an AC waveform current, which flows through the battery pack, generating heat from the battery pack's internal resistance and achieving the self-heating effect of the power battery. The control method for the switch arms is simple. The energy storage devices included in the first energy storage element are connected one-to-one with the switch arms. This provides an expansion method for expanding the energy storage scale of the energy storage module in the charging and discharging circuit, thereby reducing product costs when there are fewer energy storage devices and switch arms, while still achieving self-heating of the battery pack. On the other hand, when there are more energy storage devices and switch arms, the control complexity does not increase significantly, but the energy storage capacity of the energy storage module increases significantly. The increased energy storage capacity allows for a larger charging and discharging current to be generated in the charging and discharging circuit, which increases the heat generated by the battery's internal resistance as it flows through the battery pack. This improves the battery's temperature rise rate, improves the battery's self-heating efficiency, and allows the battery pack's temperature to reach the desired temperature as quickly as possible. Furthermore, the greater the charging and discharging energy, the more the current and frequency parameters in the battery's self-heating process can be optimized to enhance the battery's self-heating effect.

[0036] In one implementation, the switch module includes a first switch arm, and the first switch arm includes a second upper arm and a second lower arm connected in series; a first end of the first switch arm, a first end of the charge / discharge switching module, and a first end of the power supply module are connected to the same line; The second end of the first switch arm, the second end of the charge / discharge switching module, and the second end of the power supply module are connected to the same line.

[0037] The switch module uses only one switch arm to realize the battery heating function through the charge / discharge circuit, reducing the cost of the charge / discharge circuit. By controlling the on / off of the second upper arm, the second lower arm, and the charge / discharge switching module, a charge circuit and a discharge circuit that alternately switch in the charge / discharge circuit can be formed.

[0038] In one implementation, the first energy storage element includes an inductor and / or a capacitor; The connection point between the second upper arm and the second lower arm is connected to a first end of the first energy storage element, and a second end of the first energy storage element is connected to the charge / discharge switching module.

[0039] In this implementation, one end of the first energy storage element is connected to the connection point between the second upper arm and the second lower arm, and the other end of the first energy storage element is connected to the charge / discharge switching module, thereby controlling the on / off of the second upper arm, the second lower arm and the charge / discharge switching module, so that the circuit between the first energy storage element and the power supply module can be flexibly switched to a charge circuit or a discharge circuit.

[0040] In one implementation, each set of switch arms includes an upper arm and a lower arm, and each of the upper arm and the lower arm includes a switch and a diode connected in parallel, or each of the upper arm and the lower arm includes a switch.

[0041] The diode may be a freewheeling diode, which is typically used in conjunction with an inductor. A sudden change in inductor current can cause a sudden change in the voltage across the inductor, potentially damaging other circuit elements. However, when used in conjunction with a freewheeling diode, the inductor current changes more gently, avoiding sudden voltage changes and improving circuit safety. Therefore, the second upper arm and the second lower arm can both employ a switch and diode structure connected in parallel to realize the switch function, and the switching between the charging circuit and the discharging circuit can be achieved by controlling the on / off of the switches in the second upper arm and the second lower arm. The diodes in the second upper arm and the second lower arm can avoid sudden voltage changes and improve the safety of the entire charging and discharging circuit. Furthermore, in a structure in which the second upper arm and the second lower arm both include the above-mentioned switches and diodes connected in parallel, more combination control methods can be used in terms of controlling the on / off of the circuit, and the control is more flexible and varied. By rationally controlling the on / off of different devices, it is possible to form a charging circuit or a discharging circuit in the charging / discharging circuit, balance the operating frequencies of different devices, and improve the service life of each device included in the charging / discharging switching module.

[0042] On the other hand, in the case where the second upper arm and the second lower arm only include switches, a charging circuit or a discharging circuit is formed in the charging / discharging circuit, which makes it easier to control the on / off of the circuit, thereby realizing heating of the battery pack and reducing the cost of the charging / discharging circuit.

[0043] In one implementation, the switch module includes at least one pair of switch legs, each pair including a switch and a diode connected in series, and the first energy storage element in the energy storage module includes at least one energy storage device, the number of the energy storage devices is equal to the number of the switch legs, and the energy storage devices are connected in one-to-one correspondence with the switch legs.

[0044] In this implementation, the switch module includes a switch leg consisting of a switch and a diode connected in series. Using one diode and one switch connected in series reduces costs by half compared to using a switch arm consisting of two switch tubes, saving on switching costs. Furthermore, the diode is passively controlled, eliminating the need for active control, making the control strategy for a structure using one diode and one switch simpler. Furthermore, more structural variations of the switch module are provided, and the different variations of the charge / discharge switching module can be combined to create a wider variety of specific circuit structures for charge / discharge circuits, satisfying different user or industrial production needs for charge / discharge circuit structures.

[0045] In one implementation, the cathode of the diode in the switch leg is connected to the positive terminal of the power supply module, and the anode of the diode in the switch leg is connected to the negative terminal of the power supply module.

[0046] In this implementation, the cathode of the diode in the switch leg is connected to the positive electrode of the power supply module, and the cathode of the diode turns off the current, preventing direct forward current flow between the positive and negative electrodes of the power supply module via the diode, thereby improving the safety of the charge / discharge circuit.

[0047] In one implementation, the energy storage module includes an M-phase motor, the switch module includes M-phase arms, M is a positive integer, and Here, the M-phase arm, the power supply module, and the charge / discharge switching module are connected in parallel, connection points of the upper and lower arms of the M-phase arm are connected to M-phase windings of the M-phase motor in one-to-one correspondence, respectively; The charge / discharge switching module is connected to a connection point of the M-phase winding.

[0048] This method uses the electric vehicle's motor to heat the battery pack, improving motor utilization and reducing battery pack heating costs. The M-phase motor is connected not only to the M-phase arm of the switch module but also to the charge / discharge switching module, allowing current flowing through the M-phase arm to simultaneously flow into all windings of the M-phase motor and flow out the other end of all windings. This allows the current flowing through all windings of the M-phase motor to be of the same direction and magnitude, rather than alternating current with different directions. This effectively reduces the problem of excessive motor vibration noise when using the motor circuit to heat the power battery.

[0049] In one implementation, the M-phase motor includes a first M-phase motor and a second M-phase motor; A connection point of an M-phase winding of the first M-phase motor is connected to a connection point of an M-phase winding of the second M-phase motor.

[0050] In one implementation, connection points of the upper and lower arms of the M-phase arm of the switch module are connected to the M-phase windings of the first M-phase motor in a one-to-one correspondence, respectively.

[0051] In one implementation, the charge / discharge switching module includes an M-phase arm, and the connection points of the upper and lower arms of the M-phase arm of the charge / discharge switching module are respectively connected in one-to-one correspondence to the M-phase windings of the second M-phase motor.

[0052] For a power consumption device with two motors, two motors may be used to heat a battery pack, with the inverter of one motor corresponding to a switching module and the inverter of the other motor corresponding to a charge / discharge switching module. The windings of the two motors correspond to an energy storage module. By controlling the on / off of each arm of the inverters of the two motors, the charge circuit and the discharge circuit are alternately switched.

[0053] By controlling the currents flowing into each phase winding of the first M-phase motor to be equal in magnitude and in phase, vibration noise from the first M-phase motor can be effectively suppressed when using the motor circuit to heat the power battery. Similarly, by controlling the currents flowing out of each phase winding of the second M-phase motor to be equal in magnitude and in phase, vibration noise from the second M-phase motor can be effectively suppressed when using the motor circuit to heat the power battery. At the same time, the motor can be prevented from running, solving the problem of rotor heat generation in the motor and thereby extending the service life of the battery due to self-heating.

[0054] In one implementation, the power supply module includes a first battery pack; The charge / discharge switching module and the switch module are used to respond to a charge / discharge enable signal, and the waveform of the AC current generated in the charge / discharge circuit includes any one of a triangular waveform, a quasi-triangular waveform, a sine waveform, and a quasi-sine waveform.

[0055] In this implementation method, the power supply module includes one battery pack, and charging and discharging are alternately performed between the battery pack and the energy storage module. Since the energy storage module needs to discharge immediately after storing energy in a full tank, the magnitude of the heating current constantly changes. Therefore, the waveform of the AC current generated in the charging and discharging circuit including only the first battery pack is at least one of a triangular wave, a quasi-triangular wave, a sine wave, and a quasi-sine wave.

[0056] In one implementation, the power supply module includes at least a first assembled battery and a second assembled battery; the charge / discharge switching module and the switch module are used to generate an AC current with a square wave or a quasi-square wave in the charge / discharge circuit in response to a first charge / discharge enable signal, or are used to generate an AC current with any one of a triangular waveform, a quasi-triangular wave, a sine waveform, and a quasi-sine waveform in the charge / discharge circuit in response to a second charge / discharge enable signal; Here, the charge / discharge frequency corresponding to the first charge / discharge enable signal is higher than the charge / discharge frequency corresponding to the second charge / discharge enable signal.

[0057] In this implementation, ModuleThe system includes at least two battery packs, and during each heating cycle, one battery pack charges the energy storage module, and the battery pack and the energy storage module simultaneously charge another battery pack. The dual battery pack configuration effectively reduces the constraints on the magnitude and frequency of the heating current of the energy storage module. The dual battery pack heating method allows the energy of the energy storage module to be timely released to one of the battery packs so that the heating current of the battery packs can be maintained at a stable and relatively large magnitude according to a preset heating frequency. This allows the heating rate to be significantly increased by adjusting the frequency of the heating current when the batteries are in different temperature and SOC states. Because the magnitude of the heating current can be maintained at a stable value, the AC current waveform generated in the charging and discharging circuit of the dual battery pack is a square wave or quasi-square wave. Another approach is to control the frequency of the heating current and extend the duration of the discharge circuit, allowing the energy storage module to store more electrical energy before discharging. Furthermore, by extending the maintenance time of the charging circuit, all of the electrical energy in the energy storage module can be recharged into the battery pack, and in such a case, even in a charging / discharging circuit including at least two battery packs, an AC current having any one of a triangular waveform, a quasi-triangular waveform, a sine waveform, and a quasi-sine waveform can be generated.

[0058] In one implementation, a first end of the second assembled battery is connected to a first end of the charge / discharge switching module, and a second end of the second assembled battery, a second end of the first assembled battery, a second end of the switch module, and a second end of the charge / discharge switching module are connected to the same line; a first end of the first assembled battery is connected to a first end of the switch module; A tenth switch is connected between the first end of the first assembled battery and the first end of the second assembled battery.

[0059] In this implementation method, the tenth switch can control a connection method between the first assembled battery and the second assembled battery. When the tenth switch is disconnected, the negative electrode of the first assembled battery is connected to the positive electrode of the second assembled battery, and when the tenth switch is closed, the positive electrode of the first assembled battery is connected to the positive electrode of the second assembled battery. When it is necessary to heat the first assembled battery and the second assembled battery, the tenth switch is controlled to be disconnected, and the first assembled battery and the second assembled battery are heated. When it is necessary to supply power to the outside, the tenth switch is controlled to be closed, and power is supplied to the outside from the first assembled battery and the second assembled battery.

[0060] In one implementation, the first end of the energy storage module is connected to the first end of the switch module, and the second end of the energy storage module is connected to the first end of the charge / discharge switching module; or the first end of the energy storage module is connected to the second end of the switch module, and the second end of the energy storage module is connected to the second end of the charge / discharge switching module.

[0061] This implementation method provides a modified connection position of the energy storage module, allowing the charging and discharging circuit to have more variable structural configurations and be applicable to more application scenarios.

[0062] In one implementation, a capacitor is connected in parallel across the battery pack included in the power supply module.

[0063] The capacitor realizes functions such as voltage stabilization, reduces voltage fluctuations in the battery pack, and improves the stability of the battery pack voltage.

[0064] According to a second aspect, there is provided a charging / discharging system, which includes a control module and a charging / discharging circuit according to the first aspect and any one of its implementation methods, and the control module is used to control a power supply module to charge / discharge by sending a command to the charging / discharging circuit.

[0065] In this charging / discharging system, a control module is used to control a switch module and a charge / discharge switching module in the charging / discharging circuit, thereby realizing alternating switching between the charging circuit and the discharging circuit, thereby heating the assembled battery.

[0066] In one embodiment, the charging device further includes a charging device connected to the charging / discharging circuit; The charging device is used to charge the battery pack included in the power supply module via the charge / discharge circuit.

[0067] In this implementation method, the battery pack can be heated by the charge / discharge circuit, and the battery pack can be charged by the charging device.

[0068] According to a third aspect, there is provided a charge / discharge control method, which is used in the charge / discharge system according to the second aspect, and the method includes: This includes sending a charge / discharge enable signal to control the charge / discharge switching module and the switch module to be on or off, and causing the charge / discharge circuit to form a charging circuit and a discharging circuit that alternately switch, thereby generating an AC waveform current.

[0069] By controlling the on / off of the charge / discharge switching module and the switch module, an alternating charge circuit and a discharge circuit are formed between at least a first assembled battery included in the power supply module and the energy storage module. During the alternating charge and discharge circuit, an AC current is generated in the charge / discharge circuit. This AC current flows through at least the first assembled battery included in the power supply module, causing the internal resistance of the at least first assembled battery to heat, thereby achieving heating of the assembled battery included in the power supply module. The battery can be heated in the charge / discharge circuit without using the electric vehicle's motor. The motor is not affected by the frequency of the current in the charge / discharge circuit during the battery heating process, solving the conventional technical problem of high motor vibration noise during the power battery heating process. By using this charge / discharge circuit to heat the battery, the motor can drive the power vehicle normally, thereby achieving heating while driving.

[0070] In one implementation, a charge enable signal and a discharge enable signal are alternately sent to the charge / discharge switching module and the switch module at a preset frequency, thereby controlling the alternating switching between the charge circuit and the discharge circuit.

[0071] In this method, the heating rate of the battery pack is improved by controlling the frequency at which the charging and discharging circuits are switched, thereby adjusting the frequency of the AC current generated throughout the entire circuit.

[0072] In one implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit connected in series, and the switch module includes at least one pair of switch arms, each pair of switch arms including an upper arm and a lower arm; The alternating charging and discharging circuits include: a circuit between the upper arm of each pair of the switch modules, the energy storage module, the second switching circuit, and the power supply module; The lower arm of each set of the switch module includes a circuit between the energy storage module, the first switching circuit, and the power supply module.

[0073] In this implementation, the circuit between each pair of the upper arm of the switch module, the energy storage module, the second switching circuit, and the power supply module, and the circuit between each pair of the lower arm of the switch module, the energy storage module, the first switching circuit, and the power supply module are alternately switched to form an AC current in the charge / discharge circuit, which flows through the battery pack in the power supply module, causing heat to flow through the internal resistance of the battery pack, thereby achieving the effect of self-heating of the battery pack.

[0074] In one implementation, the power supply module includes at least a first assembled battery; the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, the second switching circuit includes a first lower arm; the switch module includes at least one pair of switch arms; Send a discharge enable signal to turn on the first upper arm and the lower arm of each set of the switch arms, thereby forming a discharge circuit between the power supply module, the first upper arm, the energy storage module, and the lower arm of each set of the switch arms; A charging enable signal is sent to control the first lower arm and the upper arm of each set of the switch arms to be on, thereby forming a charging circuit between the power supply module, the first lower arm, the energy storage module, and the upper arm of each set of the switch arms.

[0075] In one implementation, sending a discharge enable signal to turn on the upper arm and the first lower arm of each pair of the switch arms, thereby forming a discharge circuit between the power supply module and the upper arm of each pair of the switch arms, and between the energy storage module and the first lower arm; A charging enable signal is sent to control the lower arm of each set of switch arms and the first upper arm to be turned on, thereby forming a charging circuit between the power supply module, the lower arm of each set of switch arms, the energy storage module, and the first upper arm.

[0076] In the above two implementation methods, the first upper arm, the first lower arm, and the upper and lower arms of each set of switch arms are flexibly controlled to be turned on or off, thereby alternately switching between the discharge circuit and the charge circuit and forming an AC current in the charge / discharge circuit, thereby realizing the effect of heating the battery pack.

[0077] In one implementation, the power supply module includes at least a first assembled battery; the charge / discharge switching module includes a first switching circuit and a second switching circuit; the first switching circuit includes a third diode; the second switching circuit includes a fifth switch; and the switch module includes at least one pair of switch arms; Send a discharge enable signal to turn on the upper arm of each set of switch arms and the fifth switch, thereby forming a discharge circuit between the power supply module, the upper arm of each set of switch arms, the energy storage module, and the fifth switch; A charging enable signal is sent to control the lower arm of each set of the switch arms to be turned on, and a charging circuit is formed between the power supply module, the lower arm of each set of the switch arms, the energy storage module, and the third diode.

[0078] In one implementation, the power supply module includes at least a first assembled battery; the charge / discharge switching module includes a first switching circuit and a second switching circuit; the first switching circuit includes a seventh switch; the second switching circuit includes a fourth diode, the anode of which is connected to the negative electrode of the first assembled battery; and the switch module includes at least one pair of switch arms; Send a discharge enable signal to turn on the seventh switch and the lower arm of each set of the switch arms, thereby forming a discharge circuit between the power supply module, the seventh switch, the energy storage module, and the lower arm of each set of the switch arms; A charging enable signal is sent to control the upper arm of each set of the switch arms to be turned on, and a charging circuit is formed between the power supply module, the fourth diode, the energy storage module, and the upper arm of each set of the switch arms.

[0079] In the above two implementations, the charge / discharge switching module includes a switch and a diode connected in series, which is low cost, and the diode does not require active control but only passive control, making the control method of the entire circuit simpler.

[0080] In one implementation, the cathode of the fourth diode is connected to the negative electrode of the first assembled battery; Send a discharge enable signal to turn on the upper arm of each set of the switch arms, thereby forming a discharge circuit between the power supply module, the upper arm of each set of the switch arms, the energy storage module, and the fourth diode; A charging enable signal is sent to control the seventh switch and the lower arm of each set of the switch arms to be on, and a charging circuit is formed between the power supply module, the lower arm of each set of the switch arms, the energy storage module, and the seventh switch.

[0081] In this implementation, the orientation of the fourth diode is changed, and the modification methods of the charge / discharge circuit are increased. After the orientation of the fourth diode is changed, the control method can be simply adjusted, which simplifies the control method and reduces the cost compared to when the charge / discharge switching module includes two switches.

[0082] In one implementation, the power supply module includes at least a first assembled battery, the energy storage module includes a first M-phase motor and a second M-phase motor, the switch module includes an M-phase arm, the charge / discharge switching module includes an M-phase arm, M-phase windings of the first M-phase motor are connected in one-to-one correspondence to the M-phase arms of the switch module, M-phase windings of the second M-phase motor are connected in one-to-one correspondence to the M-phase arms of the charge / discharge switching module, and a connection point of the M-phase winding of the first M-phase motor is connected to a connection point of the M-phase winding of the second M-phase motor; sending a discharge enable signal to control the upper arm of the M-phase arm of the switch module and the lower arm of the M-phase arm of the charge / discharge switching module to be on, thereby forming a discharge circuit between the power supply module, the upper arm of the M-phase arm of the switch module, the first M-phase motor, the second M-phase motor, and the lower arm of the M-phase arm of the charge / discharge switching module; A charge enable signal is sent to control the upper arm of the M-phase arm of the charge / discharge switching module and the lower arm of the M-phase arm of the switch module to be turned on, thereby forming a charging circuit between the power supply module, the lower arm of the M-phase arm of the switch module, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the charge / discharge switching module.

[0083] In one implementation, a discharge enable signal is sent to turn on the upper arm of the M-phase arm of the charge / discharge switching module and the lower arm of the M-phase arm of the switch module, thereby forming a discharge circuit between the power supply module, the lower arm of the M-phase arm of the switch module, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the charge / discharge switching module; A charge enable signal is sent to control the upper arm of the M-phase arm of the switch module and the lower arm of the M-phase arm of the charge / discharge switching module to be on, and a charging circuit is formed between the power supply module, the lower arm of the M-phase arm of the charge / discharge switching module, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the switch module.

[0084] In the above two implementation methods, for a power consumption device with two motors, two motors can be used to heat a battery pack, with the inverter of one motor corresponding to the switching module and the inverter of the other motor corresponding to the charge / discharge switching module. The windings of the two motors correspond to the energy storage module. The charging and discharging circuits are alternately switched between the charging circuit and the discharging circuit by controlling the on / off of each arm of the inverters of the two motors.

[0085] By controlling the currents flowing into each phase winding of the first M-phase motor to be equal in magnitude and in phase, vibration noise from the first M-phase motor can be effectively suppressed when using the motor circuit to heat the power battery. Similarly, by controlling the currents flowing out of each phase winding of the second M-phase motor to be equal in magnitude and in phase, vibration noise from the second M-phase motor can be effectively suppressed when using the motor circuit to heat the power battery. At the same time, the motor can be prevented from running, solving the problem of rotor heat generation in the motor and thereby extending the service life of the battery due to self-heating.

[0086] In one implementation, the power supply module includes at least a first assembled battery and a second assembled battery; charging and discharging the first assembled battery or the second assembled battery via the charging circuit or the discharging circuit, and generating a square wave or pseudo-square wave AC current in the charging and discharging circuit; The charging and discharging includes switching between the charging and discharging states of the first assembled battery and the second assembled battery, and the charging and discharging states include charging the first assembled battery and discharging the second assembled battery, or discharging the first assembled battery and charging the second assembled battery.

[0087] In a charge / discharge circuit including two battery packs, the two battery packs alternate between charging and discharging. During each heating cycle, one battery pack is discharged while the other is charged. The dual battery pack configuration effectively reduces the constraints on the magnitude and frequency of the heating current of the energy storage module. The dual battery pack heating scheme allows the energy storage module to timely release energy to one of the battery packs so that the heating current of the battery packs can be maintained at a stable magnitude according to a preset heating frequency. This allows the heating rate to be significantly increased by adjusting the frequency of the heating current when the batteries are in different temperature and SOC states. Because the magnitude of the heating current can be maintained at a stable value, the AC current waveform generated in the dual battery pack charge / discharge circuit is a square wave or a quasi-square wave.

[0088] In one implementation, a first end of the second assembled battery is connected to a first end of the charge / discharge switching module, a second end of the second assembled battery, a second end of the first assembled battery, a second end of the switch module, and a second end of the charge / discharge switching module are connected to the same line, a first end of the first assembled battery is connected to a first end of the switch module, and a tenth switch is connected between the first end of the first assembled battery and the first end of the second assembled battery, and the method includes: The method further includes determining that the first assembled battery and the second assembled battery satisfy a heating condition and controlling the tenth switch to be turned off.

[0089] In this implementation method, the tenth switch can control a connection method between the first assembled battery and the second assembled battery. When the tenth switch is disconnected, the negative electrode of the first assembled battery is connected to the positive electrode of the second assembled battery, and when the tenth switch is closed, the positive electrode of the first assembled battery is connected to the positive electrode of the second assembled battery. When it is necessary to heat the first assembled battery and the second assembled battery, the tenth switch is controlled to be disconnected, and the first assembled battery and the second assembled battery are heated. When it is necessary to supply power to the outside, the tenth switch is controlled to be closed, and power is supplied to the outside from the first assembled battery and the second assembled battery.

[0090] In one implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, and the second switching circuit includes a first lower arm; the switch module includes at least one pair of switch arms, one end of the energy storage module is connected to a connection point between the first upper arm and the first lower arm, and the other end of the energy storage module is connected to a connection point between the upper and lower arms of the switch arms; sending a first enable signal to turn on the first upper arm and the lower arm of each set of the switch arms, thereby forming a discharge circuit between the first assembled battery, the first upper arm, the energy storage module, and the lower arm of each set of the switch arms, and discharging the first assembled battery to the energy storage module; A second enable signal is sent to turn on the first upper arm and the upper arms of each pair of the switch arms, and the first assembled battery, the first upper arm, the energy storage module, the upper arms of each pair of the switch arms, and the second assembled battery Between a charging circuit for charging the first assembled battery and the energy storage module to the second assembled battery.

[0091] In one implementation, the method comprises: The method further includes controlling the charging time for the second assembled battery by repeatedly switching on the upper arm or the lower arm of each set of switch arms.

[0092] In one implementation, the method comprises: sending a third enable signal to control the first lower arm and the upper arm of each set of the switch arms to be on, thereby forming a discharge circuit between the second assembled battery, the upper arm of each set of the switch arms, the energy storage module, and the first lower arm, and discharging the second assembled battery to the energy storage module; A fourth enable signal is sent to turn on the first upper arm and the upper arms of each set of the switch arms, and the second assembled battery, the upper arms of each set of the switch arms, the energy storage module, the first upper arm, and the first assembled battery. Between and forming a charging circuit for charging the second assembled battery and the energy storage module to the first assembled battery.

[0093] In one implementation, the method comprises: The method further includes controlling a charging time for the first assembled battery by repeatedly switching on the first upper arm or the first lower arm.

[0094] In a charge / discharge circuit including two battery packs, by controlling the on / off of a first upper arm, a first lower arm, and the upper and lower arms of each set of switch arms, one battery pack discharges to an energy storage module, and this battery pack and the energy storage module simultaneously charge another battery pack. By repeatedly switching on or off the upper arm or the lower arm of each set of switch arms, the length of time for charging each battery pack can be flexibly controlled.

[0095] In one implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, and the second switching circuit includes a first lower arm; the switch module includes at least one pair of switch arms; a first end of the energy storage module is connected to a first end of the switch module; and a second end of the energy storage module is connected to a first end of the charge / discharge switching module; Send a first enable signal to simultaneously turn on the first lower arm and the upper arm of each set of the switch arms, thereby forming a circuit for discharging the first assembled battery to the energy storage module; A second enable signal is sent to simultaneously control the lower arm and the first lower arm of each set of switch arms to be on, and the first assembled battery and the energy storage module form a circuit for charging the second assembled battery.

[0096] In one implementation, the method comprises: Sending a third enable signal to simultaneously turn on the first upper arm and the lower arm of each set of the switch arms, thereby forming a circuit for discharging the second assembled battery to the energy storage module; The method further includes transmitting a fourth enable signal to simultaneously control the first lower arm and the lower arms of each set of the switch arms to be turned on, so that the second assembled battery and the energy storage module form a circuit for charging the first assembled battery.

[0097] In one implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, and the second switching circuit includes a first lower arm; the switch module includes at least one pair of switch arms; a first end of the energy storage module is connected to a second end of the switch module, and the second end of the energy storage module is connected to a second end of the charge / discharge switching module; Send a first enable signal to simultaneously turn on the first lower arm and the upper arm of each set of the switch arms, thereby forming a circuit for discharging the second assembled battery to the energy storage module; A second enable signal is sent to simultaneously control the upper arm and the first upper arm of each set of switch arms to be on, and the second assembled battery and the energy storage module form a circuit for charging the first assembled battery.

[0098] In one implementation, the method comprises: Sending a third enable signal to simultaneously turn on the first upper arm and the lower arm of each set of the switch arms, thereby forming a circuit for discharging the first assembled battery to the energy storage module; The method further includes transmitting a fourth enable signal to simultaneously control the first upper arm and the upper arms of each set of the switch arms to be on, so that the first assembled battery and the energy storage module form a circuit for charging the second assembled battery.

[0099] In one implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, and the second switching circuit includes a first lower arm; the switch module includes at least one pair of switch arms, one end of the energy storage module is connected to a connection point between the first upper arm and the first lower arm, and the other end of the energy storage module is connected to a connection point between the upper and lower arms of the switch arms; send a first enable signal to control the first upper arm and the upper arms of each set of switch arms to be on, to form a charge / discharge circuit between the first assembled battery, the upper arms of each set of switch arms, the energy storage module, the first upper arm, and the second assembled battery, to discharge the first assembled battery to the energy storage module, and to charge the second assembled battery from the first assembled battery and the energy storage module; A second enable signal is sent to turn on the first upper arm and the upper arms of each pair of the switch arms, and the first assembled battery, the first upper arm, the energy storage module, the upper arms of each pair of the switch arms, and the second assembled battery Between a charging / discharging circuit, discharging the second assembled battery to the energy storage module, and charging the first assembled battery from the second assembled battery and the energy storage module.

[0100] In one implementation, a ninth switch is connected between the energy storage module and the charge / discharge switching module; The controller determines that the battery pack included in the power supply module satisfies the heating condition and controls the ninth switch to close, or determines that the battery pack satisfies the heating stop condition and controls the ninth switch to shut off.

[0101] The ninth switch is used to provide protection for the normal operation of components such as the energy storage module, the second energy storage element, and the switch module. When the first switching circuit and / or the second switching circuit fails in heating mode, causing a breakdown or short circuit, it is necessary to ensure that the connections between the energy storage module, the second energy storage element, and the power supply module are cut off to avoid a situation in which the energy storage module, the second energy storage element, and the power supply module are short-circuited. By controlling the ninth switch to be cut off, the risk of a short circuit in such a case can be effectively avoided.

[0102] In one implementation, before sending the charge / discharge enable signal, the method includes: determining whether a state-of-charge value of each battery pack in the power supply module is equal to or greater than a predetermined charge threshold; The method further includes, when it is determined that the state-of-charge value of each assembled battery is equal to or greater than the predetermined threshold, alternately transmitting a charge / discharge enable signal to the charge / discharge switching module and the switch module at a predetermined frequency.

[0103] In this implementation, the battery pack is heated only when the state-of-charge value of the battery pack is greater than a preset charge threshold, avoiding the situation where the power of the battery pack is too low to support the discharge electrical energy required for heating.

[0104] In one implementation, before determining whether the state-of-charge value of each assembled battery in the power supply module is equal to or greater than a predetermined charging threshold, the method further comprises: The method further includes determining whether the temperature of the power supply module is less than a predetermined temperature threshold, and if so, performing an operation of determining whether a state-of-charge value of each assembled battery in the power supply module is greater than or equal to a predetermined charge threshold.

[0105] In this implementation method, first, it is determined whether the temperature of the power supply module is lower than a preset temperature threshold, and only under low temperature conditions, it is further determined whether the state of charge value of the battery pack is equal to or greater than a preset charge threshold, and if it is determined that the state of charge value is equal to or greater than the preset charge threshold, heating of the battery pack is initiated.

[0106] In one implementation, before sending the charge / discharge enable signal, the method includes: The method further includes obtaining an operating state of the motor, and when the operating state indicates that the motor is in a non-driving state, alternately sending a charge / discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency.

[0107] In the application scenario where the motor is used to heat the battery pack, the heating of the battery pack is activated only when the motor is in a non-driving state, to avoid the heating mode affecting the normal operation of the motor.

[0108] In one implementation, before sending the charge / discharge enable signal, the method includes: The method further includes receiving a control signal sent from a vehicle controller, and when the control signal instructs the power supply module to be heated, alternately sending a charge / discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency.

[0109] In this implementation, to start heating of the battery pack, the vehicle controller may send a control signal to the motor controller, and the motor controller may control the switch module and the charge / discharge switching module to start heating.

[0110] In one implementation, before sending the charge / discharge enable signal, the method includes: The method further includes receiving request data sent from a battery management system, and, when the request data indicates that the power supply module satisfies a heating condition, alternately sending a charge / discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency.

[0111] In this implementation, the battery management system may detect whether the battery pack meets the heating condition, and if so, send request data to the vehicle controller or the motor controller, which controls the process of activating the heating.

[0112] In one implementation, the method comprises: In the charging / discharging process, the method further includes determining whether the temperature of each battery pack included in the power supply module satisfies a heating stop condition, where the heating stop condition includes that the battery pack reaches a preset temperature or the temperature rise of the battery pack is abnormal, and if so, sending a heating stop signal to the charging / discharging switching module and the switch module, where the heating stop signal triggers the charging / discharging switching module and the switch module to cut off the charging / discharging circuit.

[0113] During the charging and discharging process, the temperature of the battery pack is further monitored in real time, and if the temperature rise of the battery pack becomes abnormal or reaches a preset temperature, heating is stopped by timely control. If heating is continued even when the temperature of the battery pack reaches the preset temperature or the temperature rise becomes abnormal, it may lead to a situation where the battery pack is damaged.

[0114] In one implementation, the charging / discharging system further includes a charging device, and the method includes: When the voltage of the charging device is lower than the voltage of the power supply module, control the switch module and the charge / discharge switching module to form a circuit in which the charging device charges the energy storage module, and a circuit in which the charging device and the energy storage module simultaneously charge the power supply module; The method further includes controlling the switch module and the charge / discharge switching module when the voltage of the charging device is higher than the voltage of the power supply module, so that the charging device forms a circuit for charging the power supply module and the energy storage module, and a circuit for the energy storage module for charging the power supply module.

[0115] In this implementation, the charging / discharging circuit has both a heating mode and a charging mode, which not only heats the power battery, but also adjusts the charging voltage during the charging process of the power battery. In this way, when the voltage of the charging device and the voltage of the power battery do not match, for example, when the voltage of the charging device is lower or higher than the voltage of the power battery, the charging device can step-up charge or step-down charge the power battery through the charging / discharging circuit, thereby improving the compatibility between the charging device and the power battery.

[0116] In one implementation, the end of the energy storage module connected to the switch module is connected to one end of a charging device through a first switch tube, and the second end of the switch module is connected to the other end of the charging device, and the charging device is used to charge the power supply module through the heating module, the switch module includes at least one pair of switch arms, and the charge / discharge switching module includes a first switching circuit and a second switching circuit, and the method includes: Controlling the upper arm of each set of switch arms to be cut off; when the voltage of the charging device is lower than the voltage of the power supply module, controlling the second switching circuit and the first switch tube to be on and the first switching circuit and the lower arm of each set of switch arms to be cut off, thereby forming a circuit including the charging device, the energy storage module and the second switching circuit, for the charging device to charge the energy storage module; The method further includes controlling the first switching circuit and the first switch tube to be on and the second switching circuit and the lower arm of each set of switch arms to be off, and forming a circuit including the charging device, the energy storage module, the first switching circuit and the power supply module, so that the charging device and the energy storage module simultaneously charge the power supply module.

[0117] When the voltage of the charging device is lower than the voltage of the power supply module, a reasonable control timing is set and each sub-arm is controlled to be turned on and off, thereby forming a first stage in each charging cycle in which the charging device charges the energy storage module, and a second stage in which the charging device and the energy storage module simultaneously charge the power supply module. In this way, a certain amount of power is stored in the energy storage module during the first stage in which the charging device charges the energy storage module, so that the energy storage module and the charging device jointly charge the power supply module during the second stage, thereby reducing the voltage difference between the charging device and the power supply module and improving charging efficiency.

[0118] In one implementation, the lower arm of each set of switch arms includes a switch and a diode connected in parallel, and the method includes: When the voltage of the charging device is higher than the voltage of the power supply module, control the first switching circuit and the first switch tube to close, and the second switching circuit and the lower arm of each pair of switch arms to disconnect, so as to form a circuit including the charging device, the energy storage module, the first switching circuit and the power supply module, for the charging device to charge the power supply module and the energy storage module; The method further includes controlling the first switching circuit to close and disconnecting the second switching circuit, the lower arm of each set of switch arms, and the first switch tube, thereby forming a circuit including the energy storage module, the first switching circuit, the power supply module, and diodes in the lower arm of each set of switch arms, for the energy storage module to charge the power supply module.

[0119] When the voltage of the charging device is higher than the voltage of the power supply module, a reasonable control timing is set and each sub-arm is turned on and off to form a phase in each charging cycle in which the charging device charges the energy storage module and the power supply module, and a phase in which only the energy storage module charges the power supply module. On the one hand, when the charging device charges the energy storage module and the power supply module, the energy storage module can absorb part of the voltage, thereby appropriately reducing the voltage difference between the charging device and the power supply module. On the other hand, to avoid the charging device continuously charging the power supply module at a high voltage because the voltage of the charging device is higher than the voltage of the power supply module, the charging device and the energy storage module can alternately charge the power supply module. Here, when the charging device charges the energy storage module and the power supply module, a certain amount of power can be stored in the energy storage module, and the energy storage module can independently charge the power supply module based on this portion of the power.

[0120] According to a fourth aspect, there is provided a power consuming device, the power consuming device including the charging / discharging system according to the second aspect.

[0121] When the power consuming device is in a low-temperature environment, the power battery in the power consuming device will have a significantly reduced discharge capacity due to the low temperature, and the power battery cannot be charged in a low-temperature environment, which will affect the normal use of the power consuming device in a low-temperature environment. In the power consuming device of the embodiment of this application, the power battery is heated through a charging / discharging circuit, and a charging circuit and a discharging circuit are formed that alternate between the charging / discharging circuit, thereby generating an AC current in the charging / discharging circuit, which flows through the power battery and generates heat in the internal resistance of the power battery, thereby realizing heating of the power battery. [Brief explanation of the drawings]

[0122] In order to more clearly explain the technical solutions of the embodiments of the present application, the following briefly introduces the drawings that need to be used in the embodiments of the present application. It is obvious that the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on the drawings without exerting any creative efforts. [Figure 1] FIG. 1 is a circuit diagram of a conventional charge / discharge circuit. [Figure 2] FIG. 1 is a schematic block diagram of a charging / discharging circuit according to an embodiment of the present application. [Figure 3] FIG. 2 is another schematic block diagram of a charging / discharging circuit according to an embodiment of the present application. [Figure 4] FIG. 1 is a schematic block diagram of a charging / discharging circuit according to an embodiment of the present application, showing a first structural schematic diagram of a charging / discharging switching module. [Figure 5] FIG. 2 is a schematic block diagram of a charging / discharging circuit according to an embodiment of the present application, showing a second structural schematic diagram of a charging / discharging switching module. [Figure 6] FIG. 10 is a schematic block diagram of a charging / discharging circuit according to an embodiment of the present application, showing a third structural schematic diagram of a charging / discharging switching module. [Figure 7] 1 is a schematic block diagram of a charging / discharging circuit according to an embodiment of the present application, showing a fourth structural schematic diagram of a charging / discharging switching module. [Figure 8] FIG. 2 is another schematic block diagram of a charging / discharging circuit according to an embodiment of the present application. [Figure 9] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 10] 1 is a schematic diagram of a triangular AC current waveform generated in a charge / discharge circuit including only one battery pack according to an embodiment of the present application; [Figure 11] 1 is a schematic block diagram of a charging / discharging circuit including at least two battery packs according to an embodiment of the present application; [Figure 12] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 13] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 14] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 15] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 16] 1 is a schematic diagram of a square wave or pseudo-square wave AC current waveform generated in a charge / discharge circuit including at least two assembled batteries according to an embodiment of the present application. [Figure 17] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 18] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 19] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 20] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 21] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 22] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 23] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 24]FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 25] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 26] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 27] FIG. 2 is another schematic block diagram of a charging / discharging circuit according to an embodiment of the present application. [Figure 28] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 29] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 30] FIG. 1 is a circuit diagram of a charge / discharge circuit according to an embodiment of the present application. [Figure 31] 1 is a schematic block diagram of a charging / discharging system according to an embodiment of the present application; [Figure 32] FIG. 2 is another schematic block diagram of a charging / discharging system according to an embodiment of the present application. [Figure 33] 1 is a circuit diagram of a charging / discharging system according to an embodiment of the present application. [Figure 34] 1 is a circuit diagram of a charging / discharging system according to an embodiment of the present application. [Figure 35] 1 is a circuit diagram of a charging / discharging system according to an embodiment of the present application. [Figure 36] 1 is a flowchart of a control method in a power battery heating scenario according to an embodiment of the present application. [Figure 37] 1 is a schematic block diagram of a charge / discharge control device according to an embodiment of the present application; DETAILED DESCRIPTION OF THE INVENTION

[0123] The following describes in more detail the embodiments of the present application in conjunction with the drawings and examples. The detailed description of the embodiments and the drawings are for illustrative purposes only to explain the principles of the present application, but are not intended to limit the scope of the present application, i.e., the present application is not limited to the described embodiments.

[0124] In the description of this application, it should be explained that, unless otherwise specified, "plurality" means two or more, and the orientations or positional relationships indicated by terms such as "up," "down," "left," "right," "inside," and "outside" are merely for the convenience and simplification of the description of this application and do not indicate or imply that the referenced devices or elements must have a particular orientation or be configured and operated in a particular orientation, and should not be understood as limitations on this application. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and should not be understood as indicating or implying relative importance. "Perpendicular" does not mean strictly perpendicular, but has a margin of error. "Parallel" does not mean strictly parallel, but has a margin of error.

[0125] Any direction terms appearing in the following description refer to the directions shown in the drawings and do not limit the specific structure of the present application. It should be further explained that in the description of the present application, unless otherwise clearly defined or limited, the terms "attached," "connected," and "connected" should be understood in a broad sense, and may refer to, for example, a fixed connection, a detachable connection, or an integral connection, or may be a direct connection or an indirect connection via an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the present application according to the specific circumstances.

[0126] With the development of the times, new energy vehicles have huge market potential due to their advantages such as environmental friendliness, low noise and low usage costs, and can effectively promote energy conservation and reduction of pollutant emissions, which is beneficial to the development and progress of society.

[0127] Due to the electrochemical characteristics of power batteries, the charge and discharge capacity of power batteries is significantly limited in low temperature environments, which seriously affects the winter driving experience of customers. Therefore, it is necessary to heat the power battery in low temperature environments to ensure normal use.

[0128] The power battery in the embodiments of the present application may be a lithium ion battery, a lithium metal battery, a lead-acid battery, a nickel-cadmium battery, a nickel-metal hydride battery, a lithium-sulfur battery, a lithium-air battery, or a sodium ion battery, etc., but is not limited thereto. In terms of scale, the battery in the embodiments of the present application may be a single cell, a battery module, or a battery pack, but is not limited thereto. In terms of application scenarios, the battery may be applied in power plants such as automobiles and steamships. For example, it may be applied in a power vehicle to power the motor of the power vehicle and serve as the power source for the electric vehicle. The battery may also power other power-consuming devices in the electric vehicle, such as the interior air conditioning and on-board player.

[0129] For ease of description, the application of power batteries to new energy vehicles (power vehicles) will be described below as an example.

[0130] The drive motor and its control system are one of the core components of new energy vehicles, and their drive characteristics determine the main performance indicators of vehicle operation. The motor drive system of a new energy vehicle mainly consists of an electric motor (i.e., motor), a motor controller (e.g., inverter), various detection sensors, and a power supply. The motor is a rotating electromagnetic machine that operates using the principle of electromagnetic induction and is used to convert electrical energy into mechanical energy. During operation, it absorbs power from the electrical system and outputs mechanical power to the mechanical system.

[0131] To avoid unnecessary cost increases when heating the power battery, the motor circuit can be used to heat the power battery.

[0132] 1 shows a charging and discharging circuit diagram of a conventional power battery heating system. As shown in FIG. 1, the power battery heating system 100 may include a power supply module 110, an inverter module 120 connected to the power supply module 110, and a driving module 130 connected to the inverter module 120.

[0133] The power supply module 110 can be implemented by using a power battery itself or an external power supply module, such as a charging station. The heating energy provided by the external power supply module can be output by, for example, an external DC charger or an external AC charger after rectification, and is not specifically limited herein.

[0134] The inverter module 120 may be implemented using various types of switches. For example, the inverter module 120 may be implemented by an inverter in a motor drive system, where the inverter may be implemented using insulated gate bipolar transistor (IGBT) arm switches. Specifically, the number of arms of the inverter is the same as the number of windings in the driving module 130. For example, the driving module 130 includes a three-phase winding motor, and the inverter includes three phase arms, namely, a U-phase arm, a V-phase arm, and a W-phase arm. Here, each phase arm of the three phase arms has an upper arm and a lower arm, and the upper arm and the lower arm are respectively provided with switch units. That is, the inverter module 120 includes an upper arm switch 121 and a lower arm switch 122 in the U-phase arm, an upper arm switch 123 and a lower arm switch 124 in the V-phase arm, and an upper arm switch 125 and a lower arm switch 126 in the W-phase arm, respectively.

[0135] Specifically, drive module 130 may include winding 131 connected to the U-phase arm, winding 132 connected to the V-phase arm, and winding 133 connected to the W-phase arm. One end of winding 131 is connected to the connection point between the upper and lower arms of the U-phase arm, one end of winding 132 is connected to the connection point between the upper and lower arms of the V-phase arm, and one end of winding 133 is connected to the connection point between the upper and lower arms of the W-phase arm. The other end of winding 131, the other end of winding 132, and the other end of winding 133 are connected to the same wire.

[0136] It should be noted that the drive module 130 is not limited to a three-phase winding motor, but may also be a six-phase winding motor, a twelve-phase winding motor, etc. Accordingly, the inverter module 120 may include a three-phase arm, a six-phase arm, a twelve-phase arm, etc.

[0137] In some embodiments, the current may be modulated by controlling the periodic on / off of switches in inverter module 120. For example, the current may be modulated by controlling the periodic on / off of target upper and lower switches in inverter module 120. In one example, when the target upper switch is upper switch 121, the target lower switch is lower switch 124 and / or lower switch 126. In another example, when the target upper switch is upper switch 123, the target lower switch is lower switch 122 and / or lower switch 126. In another example, when the target upper switch is upper switch 125, the target lower switch is 122 and / or lower switch 124. In another example, when the target upper switch is upper switch 121 and / or upper switch 123, the target lower switch is 126. In another example, when the target upper switch is upper switch 123 and / or upper switch 125, the target lower switch is lower switch 122. In another example, if the target upper arm switch is upper arm switch 121 and / or upper arm switch 125, the target lower arm switch is 124.

[0138] It should be noted that the periodic on / off of the target upper arm switch and the target lower arm switch in each cycle may be the same or different, and is not limited thereto. For example, in each cycle, the upper arm switch 121 and the lower arm switch 124 are controlled to be on / off. Furthermore, for example, in the first cycle, the upper arm switch 121 and the lower arm switch 124 are controlled to be on / off, in the second cycle, the upper arm switch 123 and the lower arm switch 122 are controlled to be on / off, and in the third cycle, the upper arm switch 121, the lower arm switch 124, and the lower arm switch 126 are controlled to be on / off. That is, the target upper arm switch and the lower arm switch controlled in different cycles may be different.

[0139] As can be seen, when the charge / discharge circuit shown in Figure 1 is adopted, the target-on switch includes at least one upper arm switch and at least one lower arm switch, and since the at least one upper arm switch and the at least one lower arm switch are located on different arms, it is not possible to turn on all of the upper arms or all of the lower arms at the same time in one cycle. As a result, the current directions in the different circuits formed between the power supply module, the target upper arm switch, the target lower arm switch, and the motor winding are different, thereby generating an AC current.

[0140] The magnetomotive force of a unidirectional winding is distributed in a stepped manner in space, resulting in a pulsating magnetomotive force that regularly alters over time as the current changes. The superposition of the magnetomotive forces of three single-phase windings results in a three-phase winding composite magnetic field. Generally, the currents flowing through the three windings of a three-phase motor during heating are not all equal in magnitude. The currents flowing through two of the windings are 180° out of phase with each other, while the two phases with no phase difference are equal in magnitude. This causes the three phases of current flowing through the motor windings to be asymmetrical, and the current frequency is high, which can lead to problems with loud motor vibration noise during heating.

[0141] 2 shows a schematic block diagram of a charging / discharging circuit 200 according to an embodiment of the present application. This charging / discharging circuit 200 does not use a motor to heat the battery, and the heating process does not affect the normal operation of the motor, allowing the vehicle in which the battery is located to run normally during the battery heating process. Furthermore, not using a motor for heating fundamentally solves the problem of large motor vibration noise during the battery heating process.

[0142] 2, the charging / discharging circuit 200 includes a power supply module 210, a heating module 220, and a charging / discharging switching module 230. Here, the heating module 220 includes a switch module 240 and an energy storage module 250. The power supply module 210 includes at least a first assembled battery.

[0143] The charge / discharge switching module 230, the switch module 240, and at least the first assembled battery included in the power supply module 210 are connected in parallel. A first end of the energy storage module 250 is connected to the switch module 240, and a second end of the energy storage module 250 is connected to the charge / discharge switching module 230.

[0144] To form a charging circuit or a discharging circuit in the charging / discharging circuit shown in FIG. 2 , the charging / discharging switching module 230 and the switch module 240 need to be controlled by a charging / discharging enable signal, thereby forming an alternating charging circuit and a discharging circuit between at least the first assembled battery included in the power supply module 210 and the energy storage module 250. In the process of alternating between the charging circuit and the discharging circuit, an AC waveform current is generated in the charging / discharging circuit 200, which flows through at least the first assembled battery included in the power supply module 210, causing the internal resistance of the batteries of at least the first assembled battery to heat up, thereby achieving the effect of heating the assembled battery included in the power supply module 210.

[0145] 2 does not use a motor to heat the battery of the electric vehicle, and the motor is not affected by the frequency of the current in the charging / discharging circuit 200 during the battery heating process, solving the conventional technical problem of large motor vibration noise during the power battery heating process. When the charging / discharging circuit 200 shown in FIG. 2 is used to heat the battery, the motor drives the power vehicle normally to run, thereby realizing heating while running.

[0146] FIG. 3 shows another schematic block diagram of a charging / discharging circuit 200 according to an embodiment of the present application.

[0147] 3, the charge / discharge switching module 230 includes a first switching circuit 231 and a second switching circuit 232 connected in series. The connection point between the first switching circuit 231 and the second switching circuit 232 is connected to a second end of the energy storage module 250. The first switching circuit 231 and the second switching circuit 232 are used to be turned on or off by triggering a charge / discharge enable signal.

[0148] The charge / discharge switching module 230 includes two switching circuits, which are used to control the charge / discharge circuit to form a charge circuit or a discharge circuit. The charge / discharge enable signal controls the first switching circuit 231, the second switching circuit 232 and the switch module 240 to form an alternating charge circuit and a discharge circuit between the power supply module 210 and the energy storage module 250, generating an AC waveform current in the charge / discharge circuit 200, thereby realizing the effect of heating the battery pack included in the power supply module 210. The connection point between the first switching circuit 231 and the second switching circuit 232 is connected to the second end of the energy storage module 250, while the first end of the energy storage module 250 is connected to the switch module 240. By rationally controlling the switch module 240, the first switching circuit 231, and the second switching circuit 232 in this way, it is possible to realize alternating charging and discharging between the power supply module 210 and the energy storage module 250, thereby causing the internal resistance of the battery pack in the power supply module 210 to heat up and achieving the effect of self-heating from within the battery pack. Heating from within the battery pack results in higher heating efficiency.

[0149] FIG. 4 shows a circuit schematic diagram of a charging / discharging circuit 200 according to an embodiment of the present application.

[0150] The first switching circuit 231 and the second switching circuit 232 may form an arm structure. Here, as shown in FIG. 4 , the first switching circuit 231 includes a first upper arm 2311, and the second switching circuit 232 includes a first lower arm 2321. The connection point between the first upper arm 2311 and the first lower arm 2321 is connected to a second end of the energy storage module 250. The first upper arm 2311 and the first lower arm 2321 are turned on or off by triggering a charge / discharge enable signal. The charge / discharge enable signal controls the first upper arm 2311, the first lower arm 2321, and the switch module 240 to generate an AC waveform current in the charge / discharge circuit 200, thereby realizing the effect of heating the battery pack included in the power supply module 210.

[0151] 4, the first upper arm 2311 includes a first switch V11 and a first diode D11 connected in parallel, and the first lower arm 2321 includes a second switch V12 and a second diode D12 connected in parallel. Here, the cathode D11 of the first diode is connected to the positive electrode of the first assembled battery 211, the anode of the first diode D11 is connected to the cathode of the second diode D12, and the anode of the second diode D12 is connected to the negative electrode of the first assembled battery 211.

[0152] Here, the first switch V11 and the second switch V12 may both be switch triodes, and the first diode D11 and the second diode D12 may both be freewheeling diodes. The switch triodes and the freewheeling diodes may both be insulated gate bipolar transistors (IGBTs). Transistor , or IGBT). Freewheeling diodes are generally used in conjunction with inductors. A sudden change in inductor current causes a sudden change in the voltage across the inductor, which may damage other elements in the circuit. However, when used in conjunction with freewheeling diodes, the inductor current changes relatively slowly, preventing sudden voltage changes and improving circuit safety. Therefore, the first upper arm 2311 and the first lower arm 2321 each employ a structure in which a switch and a freewheeling diode are connected in parallel to each other, thereby realizing a switching function. By controlling the on / off of the switches in the first upper arm 2311 and the first lower arm 2321, switching between a charging circuit and a discharging circuit can be achieved. The freewheeling diodes in the first upper arm 2311 and the first lower arm 2321 prevent sudden voltage changes and improve the safety of the entire charging and discharging circuit.

[0153] When the first switch V11 is closed, the first switch V11 corresponds to a conductor, and current can flow bidirectionally through the closed first switch V11. When the first switch V11 is cut off, unidirectional current can flow through the first diode D11, from the anode to the cathode of the first diode D11. The second switch V12 and the second diode D12 have the same structures and functions on current flow as the first switch V11 and the first diode D11.

[0154] In a structure in which the first upper arm 2311 and the first lower arm 2321 both include the above-mentioned switches and diodes connected in parallel, the charge / discharge switching module 230 can have more combination control methods in terms of controlling the on / off of the circuit, and the control is more flexible and varied. By rationally controlling the on / off of different devices, it is possible to form a charge circuit or a discharge circuit in the charge / discharge circuit 200, balance the operating frequencies of different devices, and improve the service life of each device included in the charge / discharge switching module 230.

[0155] Since the first upper arm 2311 and the first lower arm 2321 are mainly responsible for on / off control of the circuit and mainly use a switch function, the first upper arm 2311 and the first lower arm 2321 may only include a switch without including a freewheeling diode. As shown in Fig. 5, the first upper arm 2311 includes a third switch V13, and the first lower arm 2321 includes a fourth switch V14. The third switch V13 and the fourth switch V14 may be a switch triode or a relay switch.

[0156] The structure in which the first upper arm 2311 and the first lower arm 2321 only include switches allows the charge / discharge switching module 230 to more easily control the on / off of the circuit so as to form a charge circuit or a discharge circuit in the charge / discharge circuit 200, thereby realizing heating of the battery pack.

[0157] In some other embodiments of the present application, the first switching circuit 231 and the second switching circuit 232 included in the charge / discharge switching module 230 may further have other modified structures. As shown in Fig. 6, the first switching circuit 231 includes a third diode D13, and the second switching circuit 232 includes a fifth switch V15. Here, the cathode of the third diode D13 is connected to the positive electrode of the first assembled battery 211, the anode of the third diode D13 is connected to one end of the fifth switch V15, and the other end of the fifth switch V15 is connected to the negative electrode of the first assembled battery 211.

[0158] In another implementation, the direction of the third diode D13 may be reversed, i.e., the anode of the third diode D13 is connected to the positive electrode of the first assembled battery 211 via the sixth switch K1, and the cathode of the third diode D13 is connected to the negative electrode of the first assembled battery 211 via the fifth switch V15.

[0159] The fifth switch V15 may be a switch triode or a relay switch.

[0160] In the charge / discharge circuit shown in FIG. 6, when the first switching circuit 231 is unidirectional, current can only flow from the anode of the third diode D13 to its cathode. When the second switching circuit 232 is bidirectional, the fifth switch V15 is closed, forming a conductor. Current can flow from the first terminal of the fifth switch V15 to the second terminal, or from the second terminal of the fifth switch V15 to the first terminal. The charge / discharge switching module 230 uses only one diode and one switch, which reduces costs by half compared to using two switch tubes and saves switching costs. Furthermore, the control strategy of the structure using only one diode and one switch is simpler, and the diode is passively controlled, eliminating the need for active control. In this way, the charge / discharge switching module 230 can flexibly switch between the charge circuit and the discharge circuit in the charge / discharge circuit, thereby generating AC current in the charge / discharge circuit.

[0161] As shown in FIG. 6, in an embodiment in which the first switching circuit 231 includes the third diode D13, the first switching circuit 231 may further include a sixth switch K1, one end of which is connected to the positive electrode of the first assembled battery 211 and the other end of which is connected to the negative electrode of the third diode D13.

[0162] Here, the sixth switch K1 may be a triode or a relay switch, and is installed to prevent current from flowing through the third diode D13 when the battery does not need to be heated, thereby preventing circuit failure caused by current flowing through the third diode when the battery does not need to be heated, and improving the service life of the electrical devices in the circuit.

[0163] 7 shows a modified structure of the charge / discharge switching module 230 shown in FIG. 7. As shown in FIG. 7, the first switching circuit 231 includes a seventh switch V16, and the second switching circuit 232 includes a fourth diode D14. One end of the seventh switch V16 is connected to the positive electrode of the first assembled battery 211, and the other end of the seventh switch V16 is connected to the negative electrode of the fourth diode D14. The anode of the fourth diode D14 is connected to the negative electrode of the first assembled battery 211.

[0164] In another implementation, the direction of the fourth diode D14 may be reversed, i.e., the anode of the fourth diode D14 is connected to the seventh switch V16, and the cathode of the fourth diode D14 is connected to the negative electrode of the first assembled battery 211.

[0165] In the charge / discharge circuit shown in FIG. 7, when the first switching circuit 231 is bidirectionally on, the seventh switch V16 corresponds to a conductor after it is closed, and current can flow from the first terminal of the seventh switch V16 to the second terminal, or from the second terminal of the seventh switch V16 to the first terminal. When the second switching circuit 232 is unidirectionally on, current can only flow from the anode of the fourth diode D14 to its cathode. The charge / discharge switching module 230 employs only one diode and one switch, which halves the cost compared to employing two switch tubes and saves the cost of switching. Furthermore, the control strategy of the structure employing only one diode and one switch is simpler, and the diode is passively controlled, eliminating the need for active control. In this way, the charge / discharge switching module 230 can flexibly switch between the charge circuit and the discharge circuit in the charge / discharge circuit, thereby generating AC current in the charge / discharge circuit.

[0166] 7, in an embodiment in which the second switching circuit 232 includes the fourth diode D14, the second switching circuit 232 further includes an eighth switch K2. The eighth switch K2 is connected in series between the fourth diode D14 and the negative electrode of the first assembled battery 211.

[0167] Here, the eighth switch K2 may be a triode or a relay switch, and is installed to prevent current from flowing through the fourth diode D14 when the battery does not need to be heated, thereby preventing circuit failure caused by current flowing through the fourth diode when the battery does not need to be heated, and improving the service life of the electrical devices in the circuit.

[0168] The energy storage module 250 in the above Figures 2-7 may include only a first energy storage element 251 (not shown in Figures 2-7), where the first energy storage element 251 includes at least one inductor, a first end of the first energy storage element 251 is connected to the switch module 240, and a second end of the first energy storage element 251 is connected to the charge / discharge switching module 230.

[0169] The energy storage module 250 may include only a first energy storage element 251, or the first energy storage element 251 may include one or more inductors. By installing the first energy storage element 251, the electrical energy released by the power supply module 210 when the charging / discharging circuit is switched to a discharging circuit may be stored in the first energy storage element 251. When the charging / discharging circuit is switched to a charging circuit, the first energy storage element 251 may recharge the stored electrical energy to the power supply module 210, causing an AC current to flow through the power supply module 210, which generates heat from the internal resistance of the battery pack in the power supply module 210 and achieves the effect of internal heating of the battery pack. Compared to external heating of the battery pack, the self-heating method of internally heating the battery pack provides a better heating effect.

[0170] 8, the energy storage module 250 may further include a second energy storage element 260, which is connected between the second end of the first energy storage element 251 and the charge / discharge switching module 230. The second energy storage element 260 includes at least one inductor and / or capacitor.

[0171] A second energy storage element 260 is added between the first energy storage element 251 and the charge / discharge switching module 230, and the first energy storage element 251 is connected in series with the second energy storage element 260. When a discharge circuit is formed in the charge / discharge circuit, the electrical energy released by the power supply module 210 can be jointly stored by the first energy storage element 251 and the second energy storage element 260, thereby storing more energy. When the charge / discharge circuit is switched to a charge circuit, the first energy storage element 251 and the second energy storage element 260 recharge the stored electrical energy into the battery pack of the power supply module 210. This larger electrical energy can be charged and discharged, thereby forming a larger charging / discharging current in the charge / discharge circuit. The larger the current, the more heat is generated due to the internal resistance of the battery when it flows through the battery pack, thereby improving the temperature rise rate of the battery pack, improving the efficiency of battery self-heating, and allowing the temperature of the battery pack to be raised to a desired temperature as quickly as possible. The more energy there is in the charge and discharge, the more the current and frequency parameters in the battery's self-heating process can be optimized, thereby enhancing the battery's self-heating effect.

[0172] After adding the second energy storage element 260, when a discharge circuit is formed in the charge / discharge circuit, more energy can be stored by storing energy through the energy storage module 250 and the second energy storage element 260, thereby optimizing the current and frequency parameters in the battery self-heating process and improving the self-heating effect of the battery.

[0173] A ninth switch K3 may be connected between the energy storage module 250 and the charge / discharge switching module 230, and the ninth switch K3 is connected in series with the second energy storage element 260. The ninth switch K3 may be connected between the energy storage module 250 and the second energy storage element 260, or may be connected between the second energy storage element 260 and the charge / discharge switching module 230.

[0174] The ninth switch K3 is used to provide protection for the normal operation of components such as the energy storage module 250, the second energy storage element 260, and the switch module 240. Specifically, if the first switching circuit 231 and / or the second switching circuit 232 fails in the heating mode, causing a breakdown or short circuit, it is necessary to ensure that the connections between the energy storage module 250, the second energy storage element 260, and the power supply module 210 are cut off to avoid a situation in which the energy storage module 250, the second energy storage element 260, and the power supply module 210 are short-circuited. By controlling the ninth switch K3, the risk of a short circuit that may exist in such a case can be effectively avoided.

[0175] In some embodiments of the present application, the switch module 240 includes at least one pair of switch arms, and the energy storage module 250 includes at least one energy storage device, the number of which is equal to the number of the switch arms, and the energy storage devices are connected to the switch arms in a one-to-one correspondence. A connection point at the second end of each energy storage device is connected to the charge / discharge switching module 230.

[0176] Here, each set of switch arms includes an upper arm and a lower arm, and each of the upper arm and the lower arm includes a switch and a diode connected in parallel, or each of the upper arm and the lower arm includes a switch, where the switch may be a switch triode or a relay switch.

[0177] The switch module 240 includes at least one pair of switch arms, and the switch arms have a symmetrical structure. By controlling the on / off of each pair of switch arms and the charge / discharge switching module 230, a charging circuit and a discharging circuit are formed, which are alternately switched in the charging / discharging circuit, thereby charge / discharge circuitThis generates an AC waveform current, which flows through the battery pack, generating heat from the battery pack's internal resistance and achieving the self-heating effect of the power battery. The control method for the switch arms is simple. The energy storage devices included in the first energy storage element are connected one-to-one with the switch arms. This provides an expansion method for expanding the energy storage scale of the energy storage module 250 in the charging and discharging circuit, thereby reducing product costs when there are fewer energy storage devices and switch arms, while still achieving self-heating of the battery pack. On the other hand, when there are more energy storage devices and switch arms, the control complexity does not increase significantly, but the energy storage capacity of the energy storage module 250 increases significantly. The increased energy storage capacity allows for a larger charging and discharging current to be generated in the charging and discharging circuit, which increases the heat generated by the battery's internal resistance as it flows through the battery pack. This improves the rate at which the battery pack temperature rises, improves the efficiency of battery self-heating, and allows the battery pack temperature to reach the desired temperature as quickly as possible. Furthermore, the greater the charging and discharging energy, the more the current and frequency parameters in the battery self-heating process can be optimized to enhance the self-heating effect of the battery.

[0178] By controlling the on / off of each pair of switch arms and the charge / discharge switching module 230, a charging circuit and a discharging circuit are formed that alternately switch between the charging and discharging circuits, thereby charge / discharge circuit This current flows through the battery pack, causing the internal resistance of the battery pack to heat up, thereby achieving the effect of self-heating of the power battery.

[0179] 9, the switch module 240 includes a first switch arm 241, which includes a second upper arm 2411 and a second lower arm 2412 connected in series. A first end of the first switch arm 241, a first end of the charge / discharge switching module 230, and a first end of the power supply module 210 are connected to the same line. A second end of the first switch arm 241, a second end of the charge / discharge switching module 230, and a second end of the power supply module 210 are connected to the same line.

[0180] The energy storage module 250 includes a first energy storage element, the first energy storage element including at least one inductor, a first end of the first energy storage element connected to the switch module, and a second end of the first energy storage element connected to the charge / discharge switching module 230. The first energy storage element includes at least one inductor, or the first energy storage element includes at least one inductor and / or capacitor. A connection point between the second upper arm 2411 and the second lower arm 2412 is connected to a first end of the energy storage module 250, and a second end of the energy storage module 250 is connected to the charge / discharge switching module 230.

[0181] 9 is schematically illustrated using an inductor L1 as an example, but in actual applications, the first energy storage element 251 may be a capacitor, multiple inductors connected in series, or an inductor and a capacitor connected in series. The second upper arm 2411 and the second lower arm 2412 are both schematically illustrated using a switch triode and a freewheeling diode connected in parallel. The second upper arm 2411 includes a tenth switch V17 and a fifth diode D15 connected in parallel, and the second lower arm 2412 includes an eleventh switch V18 and a sixth diode D16 connected in parallel. In actual applications, the second upper arm 2411 and the second lower arm 2412 may have any structure capable of implementing a switch function. For example, the second upper arm 2411 and the second lower arm 2412 may both be switch triodes.

[0182] 9, the charge / discharge switching module 230 includes a first upper arm 2311 and a first lower arm 2321 connected in series, the first upper arm 2311 including a first switch V11 and a first diode D11 connected in parallel, and the first lower arm 2321 including a second switch V12 and a second diode D12 connected in parallel. In addition to the structure shown in FIG. 9, the charge / discharge switching module 230 may have any one of the structures shown in FIGS. 5-7.

[0183] 9, the first upper arm 2311, the second upper arm 2411, and the positive electrode of the first assembled battery 211 are connected to the same line, and the first lower arm 2321, the second lower arm 2412, and the negative electrode of the first assembled battery 211 are connected to the same line. One end of the inductor L1 is connected to the connection point between the second upper arm 2411 and the second lower arm 2412, and the other end of the inductor L1 is connected to the connection point between the first upper arm 2311 and the first lower arm 2321.

[0184] 9, a capacitor C2 may be connected in parallel across the first assembled battery 211. This capacitor C2 provides functions such as voltage stabilization, reduces voltage fluctuations in the first assembled battery 211, and improves the stability of the voltage of the first assembled battery 211. In this way, the motor controller's requirements for battery voltage sampling accuracy during driving can be reduced.

[0185] In a powered vehicle, the control module controls the switch module 240 and the charge / discharge switching module 230 to alternately switch between a charge circuit and a discharge circuit in the charge / discharge circuit. Specifically, in the circuit structure shown in Fig. 9, the control module controls the on / off of the first upper arm 2311, the first lower arm 2321, the second upper arm 2411, and the second lower arm 2412 to form a circuit in which the first assembled battery 211 discharges to the inductor L1, and a circuit in which the inductor L1 charges the first assembled battery 211, thereby heating the first assembled battery 211 during the discharging and charging processes.

[0186] The control module may be a VCU (vehicle controller) or an MCU (motor controller), or the VCU and MCU may be other relatively independent control modules, such as a domain controller, and the embodiments of the present application are not specifically limited thereto.

[0187] As can be seen, when the first assembled battery 211 is heated, the first upper arm 2311, the first lower arm 2321, the second upper arm 2411, and the second lower arm 2412 are controlled to be turned on or off to form a circuit in which the first assembled battery 211 discharges to the inductor L1, and a circuit in which the inductor L1 charges the first assembled battery 211. By switching between the discharge circuit and the charge circuit, repeated charging and discharging is performed between the first assembled battery 211 and the inductor L1. Because an alternating current flows inside the battery during the discharge and charge processes, the temperature of the battery rises, resulting in self-heating of the battery.

[0188] Specifically, each heating cycle for heating the first assembled battery 211 may include a first stage and a second stage. Here, in the first stage, the control module controls the first upper arm 2311 and the second lower arm 2412 to be simultaneously turned on and the first lower arm 2321 and the second upper arm 2411 to be turned off, thereby forming a circuit including the first assembled battery 211, the first upper arm 2311, the inductor L1, and the second lower arm 2412. The first assembled battery 211 discharges to the inductor L1, and the inductor L1 can store electrical energy. The discharge current path is from the positive electrode of the first assembled battery 211 to V11 to inductor L1 to V18 to the negative electrode of the first assembled battery 211.

[0189] In the second stage, the first lower arm 2321 and the second upper arm 2411 are simultaneously turned on, and the first upper arm 2311 and the second lower arm 2412 are controlled to be cut off, forming a circuit including the first assembled battery 211, the first lower arm 2321, the inductor L1, and the second upper arm 2411, and the inductor L1 charges the first assembled battery 211. The charging current path is from the negative electrode of the first assembled battery 211 to V12 to inductor L1 to V17 to the positive electrode of the first assembled battery 211.

[0190] In another implementation, in the first stage, the control module first controls the first lower arm 2321 and the second upper arm 2411 to be simultaneously turned on and the first upper arm 2311 and the second lower arm 2412 to be turned off, thereby forming a discharge circuit including the first assembled battery 211, the second upper arm 2411, the inductor L1, and the first lower arm 2321. The first assembled battery 211 discharges to the inductor L1, and the inductor L1 stores electrical energy. The discharge current path is from the positive electrode of the first assembled battery 211 to V17 to inductor L1 to V12 to the negative electrode of the first assembled battery 211. In the second stage, the first upper arm 2311 and the second lower arm 2412 are simultaneously turned on, and the first lower arm 2321 and the second upper arm 2411 are controlled to be cut off, forming a charging circuit including the first assembled battery 211, the second lower arm 2412, the inductor L1, and the first upper arm 2311, and the inductor L1 charges the first assembled battery 211. The charging current path is from the negative electrode of the first assembled battery 211 to V18 to inductor L1 to V11 to the positive electrode of the first assembled battery 211.

[0191] In this application, by designing a rational control timing and controlling the on / off of the first upper arm 2311, the first lower arm 2321, the second upper arm 2411, and the second lower arm 2412, a circuit is formed in which the first assembled battery 211 discharges to the inductor L1, and a circuit in which the inductor L1 charges the first assembled battery 211. By switching between the discharge circuit and the charge circuit, repeated charging and discharging is performed between the first assembled battery 211 and the inductor L1, thereby realizing continuous heating of the battery.

[0192] In some other embodiments of the present application, the energy storage module 250 may include a combination of multiple inductors and / or capacitors, as long as the specific structure of the energy storage module 250 can store energy in accordance with the first assembled battery 211. The switch module 240 may include multiple sets of switch arms. When the first assembled battery 211 is heated by this charging / discharging circuit, the vehicle motor can operate normally, so operating in heating mode does not affect the normal running of the vehicle.

[0193] In the above embodiments, the power supply module 210 includes at least a first assembled battery 211. FIG. 9 illustrates an example in which the power supply module 210 includes only the first assembled battery 211. In an embodiment in which the charging / discharging circuit includes only one assembled battery, the energy storage module 250 stores energy during the discharging phase of the assembled battery, and charges the assembled battery during the charging phase. During this charging / discharging process, the energy storage module 250 must immediately discharge energy after storing a full tank of energy. Therefore, the current amplitude value in the charging / discharging circuit immediately drops after reaching a maximum value, and the generated AC current waveform is one of a triangular waveform, a quasi-triangular waveform, a sinusoidal waveform, and a quasi-sinusoidal waveform. FIG. 10 shows a schematic diagram of a triangular AC current waveform generated in a charging / discharging circuit including only one assembled battery.

[0194] In the embodiment of the present application, the quasi-triangular wave is distorted from a regular triangular waveform to a quasi-triangular wave due to some equipment errors or issues such as current modulation accuracy. The errors that cause the distortion may include issues such as delayed equipment response time and electromagnetic interference. Each period of the triangular wave and the quasi-triangular wave has only one maximum discharge peak value and one maximum charge peak value. Referring to the triangular wave shown in FIG. 10, for the quasi-triangular wave, the maximum discharge peak value I1 occurs only at time t1 and the maximum charge peak value -I2 occurs at time t2, with the current directions of I1 and -I2 being different.

[0195] Similarly, a pseudo-sine wave is also a waveform that is distorted from a regular sine wave to a pseudo-sine wave due to some errors in the equipment or problems such as current modulation accuracy. Each cycle of a sine wave and a pseudo-sine wave has only one maximum discharge peak value and one maximum charge peak value.

[0196] In some other embodiments of the present application, the power supply module 210 may further include two or more battery packs, and the charge / discharge circuit of the embodiments of the present application may simultaneously heat any two battery packs in the power supply module 210. The multiple battery packs included in the power supply module 210 may be divided into two sets of battery packs, each set of battery packs connected to the beginning (i.e., the negative terminal of the preceding battery pack is connected to the positive terminal of the adjacent subsequent battery pack) to form a single battery pack, thereby allowing all battery packs to be heated simultaneously via the charge / discharge circuit. In the embodiments of the present application, the heating module 220 and the charge / discharge switching module 230 are collectively referred to as a battery heating device 270. As shown in FIG. 11 , the battery heating device 270 is connected to the power supply module 210 and is used to heat the power supply module 210. The power supply module 210 includes N battery packs, such as a first battery pack 211, a second battery pack 212, ..., an Nth battery pack, etc., as shown in FIG. 11 , where N is a positive integer greater than or equal to 2. In the embodiment of the present application, the battery heating device 270 can simultaneously heat two of the battery packs. That is, the N battery packs are divided into multiple groups, each of which has two battery packs, and the battery heating device 270 heats two of the battery packs simultaneously. The embodiment of the present application does not limit how the N battery packs are grouped, nor does it limit the order in which the battery packs are heated. In another implementation, the N battery packs may be divided into two groups, and the multiple battery packs in each group may correspond to one larger battery pack, thereby making the N battery packs equivalent to two battery packs.

[0197] Based on the above analysis, when two or more assembled batteries are included, the configuration can be simplified to the case where two assembled batteries are heated simultaneously. In the following, the first assembled battery 211 and the second assembled battery 212 are taken as an example to describe in detail the charging / discharging circuit structure and control process for simultaneously heating the first assembled battery 211 and the second assembled battery 212.

[0198] Here, a first end of the first assembled battery 211 is connected to a first end of the charge / discharge switching module 230, a second end of the first assembled battery 211, a second end of the second assembled battery 212, a second end of the switch module 240, and a second end of the charge / discharge switching module 230 are connected to the same line, a first end of the second assembled battery 212 is connected to a first end of the switch module 240, and a tenth switch K4 is connected between the first end of the first assembled battery 211 and the first end of the second assembled battery 212.

[0199] In the application scenario of two assembled batteries, the structures of the switch module 240 and the charge / discharge switching module 230 are the same as those in the application scenario of a single assembled battery. The energy storage module 250 is connected between the charge / discharge switching module 230 and the switch module 240. In one implementation, one end of the energy storage module 250 is connected to the connection point between the first switching circuit 231 and the second switching circuit 232 included in the charge / discharge switching module 230, and the other end of the energy storage module 250 is connected to the connection point between the upper and lower arms of each pair of switch arms in the switch module 240. In another implementation, the energy storage module 250 does not need to be connected between the connection point between the first switching circuit 231 and the second switching circuit 232 and the connection point between the upper and lower arms of each pair of switch arms. Instead, it is connected between the first end of the switch module 240 and the first end of the charge / discharge switching module 230, or between the second end of the switch module 240 and the second end of the charge / discharge switching module 230. Here, the first end of the switch module 240 and the first end of the charge / discharge switching module 230 are the ends of the switch module 240 that are connected to the same line as the charge / discharge switching module 230, and the second end of the switch module 240 and the second end of the charge / discharge switching module 230 are the other ends of the switch module 240 that are connected to the same line as the charge / discharge switching module 230.

[0200] The first terminal of the first assembled battery 211 may be the positive terminal of the first assembled battery 211, and the second terminal of the first assembled battery 211 may be the negative terminal of the first assembled battery 211. The first terminal of the second assembled battery 212 may be the positive terminal of the second assembled battery 212, and the second terminal of the second assembled battery 212 may be the negative terminal of the second assembled battery 212.

[0201] When the tenth switch K4 is turned off, the negative electrode of the first assembled battery 211 is connected to the positive electrode of the second assembled battery 212, and when the tenth switch K4 is closed, the positive electrode of the first assembled battery 211 is connected to the positive electrode of the second assembled battery 212. When it is necessary to heat the first assembled battery 211 and the second assembled battery 212, the tenth switch K4 may be controlled to be turned off. On the other hand, in other cases, for example, when the first assembled battery 211 and the second assembled battery 212 supply power to a power system or the like, the tenth switch K4 may be controlled to be closed.

[0202] When the tenth switch K4 is turned off, the positive electrode of the first assembled battery 211 is connected to the positive electrode of the second assembled battery 212, and the negative electrode of the first assembled battery 211 is connected to the negative electrode of the second assembled battery 212. In this way, the current flows between the first assembled battery 211 and the second assembled battery 212. 212 , and energy exchange between the first assembled battery 211 and the second assembled battery 212 is realized.

[0203] 12 includes a first assembled battery 211 and a second assembled battery 212. The charge / discharge switching module 230 includes a first upper arm 2311 and a first lower arm 2321 connected in series. The first upper arm 2311 includes a first switch V11 and a first diode D11 connected in parallel. The first lower arm 2321 includes a second switch V12 and a second diode D12 connected in parallel. The energy storage module 250 includes an inductor L1. The switch module 240 includes a second upper arm 2411 and a second lower arm 2412. The second upper arm 2411 includes a tenth switch V17 and a fifth diode D15 connected in parallel. The second lower arm 2412 includes an eleventh switch V18 and a sixth diode D16 connected in parallel.

[0204] Here, the first upper arm 2311, the second upper arm 2411, and the positive electrode of the second assembled battery 212 are connected to the same line, and the first lower arm 2321, the second lower arm 2412, the negative electrode of the first assembled battery 211, and the negative electrode of the second assembled battery 212 are connected to the same line. One end of inductor L1 is connected to the connection point between the second upper arm 2411 and the second lower arm 2412, and the other end of inductor L1 is connected to the connection point between the first upper arm 2311 and the first lower arm 2321. The positive electrode of the first assembled battery 211 is connected to the second upper arm 2411. The connection point between the positive electrode of the first assembled battery 211 and the second upper arm 2411 is connected to one end of a tenth switch K4, and the other end of the tenth switch K4, the first upper arm 2311, and the positive electrode of the second assembled battery 212 are connected to the same line.

[0205] In FIG. 12 , the first upper arm 2311, the first lower arm 2321, the second upper arm 2411, and the second lower arm 2412 all include a switch triode and a freewheeling diode connected in parallel. This structure may be replaced with a structure in which the first upper arm 2311, the first lower arm 2321, the second upper arm 2411, and the second lower arm 2412 shown in FIG. 13 all include only a switch triode, and the switch triode may be replaced with any component having a switching function, such as a relay switch. In actual applications, any one of the first upper arm 2311, the first lower arm 2321, the second upper arm 2411, and the second lower arm 2412 may include a switch triode and a freewheeling diode connected in parallel, or may include only a switch; this application is not limited thereto. Furthermore, the charge / discharge switching module 230 may not include the first upper arm 2311 and the first lower arm 2321, but may instead have a combined structure including a diode and a switch connected in series, as shown in FIG. 6 or 7. The energy storage module 250 may include multiple inductors connected in series, or an inductor and a capacitor connected in series, or the like.

[0206] The energy storage module 250 may be connected between the charge / discharge switching module 230 and the switch module 240. For example, as shown in Figures 12 and 13, one end of the energy storage module 250 is connected between the first upper arm 2311 and the first lower arm 2321, and the other end of the energy storage module 250 is connected between the second upper arm 2411 and the second lower arm 2412.

[0207] 14 , for example, one end of the energy storage module 250 is connected to the first end E11 of the charge / discharge switching module 230, and the other end of the energy storage module 250 is connected between the first end E21 of the switch module 240. A conductor connects a connection point between the first upper arm 2311 and the first lower arm 2321 and a connection point between the second upper arm 2411 and the second lower arm 2412. The first lower arm 2321 is connected to the negative electrode of the first assembled battery 211, and the second lower arm 2412 is connected to the negative electrode of the second assembled battery 212, and the first lower arm 2321 and the second lower arm 2412 are not connected to each other.

[0208] 15 , for example, one end of the energy storage module 250 is connected to the second end E12 of the charge / discharge switching module 230, and the other end of the energy storage module 250 is connected between the second end E22 of the switch module 240. A conductor connects a connection point between the first upper arm 2311 and the first lower arm 2321 and a connection point between the second upper arm 2411 and the second lower arm 2412. The first upper arm 2311 is connected to the positive electrode of the first assembled battery 211, and the second upper arm 2411 is connected to the positive electrode of the second assembled battery 212, and the first upper arm 2311 and the second upper arm 2411 are not connected to each other.

[0209] 12-15, for example, a capacitor C1 may be connected in parallel across the first assembled battery 211, and for example, a capacitor C2 may be connected in parallel across the second assembled battery 212. These capacitors C1 and C2 provide functions such as voltage stabilization, reducing voltage fluctuations between the first assembled battery 211 and the second assembled battery 212 and improving the stability of the voltage between the second assembled battery 212 and the second assembled battery 212. In this way, the motor controller's requirements for battery voltage sampling accuracy during driving can be reduced.

[0210] In the powered vehicle, a control module such as a VCU or an MCU controls the switch module 240 and the charge / discharge switching module 230 to form a circuit in which the second assembled battery 212 discharges to the energy storage module 250 and a circuit in which the energy storage module 250 and the second assembled battery 212 charge the first assembled battery 211, thereby heating the first assembled battery 211 and the second assembled battery 212 during the discharging and charging processes. And / or, the control module controls the switch module 240 and the charge / discharge switching module 230 to form a circuit in which the first assembled battery 211 discharges to the energy storage module 250 and a circuit in which the energy storage module 250 and the first assembled battery 211 charge the second assembled battery 212, thereby heating the first assembled battery 211 and the second assembled battery 212 during the discharging and charging processes.

[0211] That is, when the control module heats the first assembled battery 211 and the second assembled battery 212, it needs to control the switch module 240 and the charge / discharge switching module 230, and by controlling the on / off of the switch module 240 and the charge / discharge switching module 230, a circuit is formed in which one of the first assembled battery 211 and the second assembled battery 212 discharges to the energy storage module 250, and a circuit is formed in which this battery and the energy storage module 250 charge the other assembled battery. Because current flows through both the two assembled batteries during the discharging and charging processes by switching between the discharging circuit and the charging circuit, the temperature of the two assembled batteries increases, achieving simultaneous heating of the two assembled batteries with relatively high heating efficiency.

[0212] 12 and 13 , when the first assembled battery 211 and the second assembled battery 212 need to be heated, each heating cycle includes a first stage and a second stage. In the first stage, the control module first controls the tenth switch K4 to be turned off. The control module simultaneously controls the first upper arm 2311 and the second lower arm 2412 to be turned on, thereby forming a circuit including the first assembled battery 211, the first upper arm 2311, the energy storage module 250, and the second lower arm 2412 for discharging from the first assembled battery 211 to the energy storage module 250. The discharging current path is from the positive electrode of the first assembled battery 211 to V11 to inductor L1 to V18 to the negative electrode of the first assembled battery 211. In the second stage, the first upper arm 2311 and the second upper arm 2411 are simultaneously controlled to be on, forming a circuit including the first assembled battery 211, the first upper arm 2311, the energy storage module 250, the second upper arm 2411, and the second assembled battery 212, for the first assembled battery 211 and the energy storage module 250 to charge the second assembled battery 212. The charging current path is from the positive electrode of the first assembled battery 211 to V11 to inductor L1 to V17 to the positive electrode of the second assembled battery 212 to the negative electrode of the second assembled battery 212 to the negative electrode of the first assembled battery 211. In order to keep this state constant, the repeated switching between V17 and V18 is controlled, thereby controlling the charging time for the second assembled battery 212.

[0213] Furthermore, each heating cycle may further include a third stage and a fourth stage in addition to including the first stage and the second stage. In the third stage, the control module simultaneously controls the first lower arm 2321 and the second upper arm 2411 to be on, thereby forming a circuit including the second assembled battery 212, the second upper arm 2411, the energy storage module 250, and the first lower arm 2321 for discharging from the second assembled battery 212 to the energy storage module 250. The discharging current path is from the positive electrode of the second assembled battery 212 to V17 to the inductor L1 to V12 to the negative electrode of the second assembled battery 212. In the fourth stage, the first upper arm 2311 and the second upper arm 2411 are simultaneously controlled to be on, forming a circuit including the second assembled battery 212, the second upper arm 2411, the energy storage module 250, the first upper arm 2311, and the first assembled battery 211, for the second assembled battery 212 and the energy storage module 250 to charge the first assembled battery 211. The charging current path is from the positive electrode of the second assembled battery 212 → V17 → inductor L1 → V11 → the positive electrode of the first assembled battery 211 → the negative electrode of the first assembled battery 211 → the negative electrode of the second assembled battery 212. In order to keep this state constant, the charging time for the first assembled battery 211 can be controlled by controlling repeated switching between the first upper arm 2311 and the first lower arm 2321.

[0214] 14 , in a first stage, when the first lower arm 2321 and the second upper arm 2411 are simultaneously controlled to be on, a circuit is formed in which the first assembled battery 211 discharges to the energy storage module 250, and the discharging current path is the positive electrode of the first assembled battery 211 → inductor L1 → V17 → V12 → negative electrode of the first assembled battery 211. In a second stage, when the second lower arm 2412 and the first lower arm 2321 are simultaneously controlled to be on, a circuit is formed in which the first assembled battery 211 and the energy storage module 250 charge the second assembled battery 212, and the charging current path is the positive electrode of the first assembled battery 211 → inductor L1 → positive electrode of the second assembled battery 212 → negative electrode of the second assembled battery 212 → V18 → V12 → negative electrode of the first assembled battery 211.

[0215] Furthermore, in a third stage, the first upper arm 2311 and the second lower arm 2412 are simultaneously controlled to be ON, forming a circuit in which the second assembled battery 212 discharges to the energy storage module 250, with the discharging current path being the positive electrode of the second assembled battery 212 → inductor L1 → V11 → V18 → negative electrode of the second assembled battery 212. In a fourth stage, the first lower arm 2321 and the second lower arm 2412 are simultaneously controlled to be ON, forming a circuit in which the second assembled battery 212 and the energy storage module 250 charge the first assembled battery 211, with the charging current path being the positive electrode of the second assembled battery 212 → inductor L1 → positive electrode of the first assembled battery 211 → negative electrode of the first assembled battery 211 → V12 → V18 → negative electrode of the second assembled battery 212. Here, by controlling the switch tube on each arm, it is possible to turn on and off each arm.

[0216] 15 , in a first stage, when the first lower arm 2321 and the second upper arm 2411 are simultaneously controlled to be on, a circuit is formed in which the second assembled battery 212 discharges to the energy storage module 250, and the discharging current path is the positive electrode of the second assembled battery 212 → V17 → V12 → inductor L1 → negative electrode of the second assembled battery 212. In a second stage, when the second upper arm 2411 and the first upper arm 2311 are simultaneously controlled to be on, the second assembled battery 212 and the energy storage module 250 form a circuit in which the first assembled battery 211 is charged, and the charging current path is the positive electrode of the second assembled battery 212 → V17 → V11 → positive electrode of the first assembled battery 211 → negative electrode of the first assembled battery 211 → inductor L1 → negative electrode of the second assembled battery 212.

[0217] Furthermore, in a third stage, the first upper arm 2311 and the second lower arm 2412 are controlled to be turned on simultaneously, forming a circuit in which the first assembled battery 211 discharges to the energy storage module 250, with the discharging current path being the positive electrode of the first assembled battery 211 → V11 → V18 → inductor L1 → negative electrode of the first assembled battery 211. In a fourth stage, the first upper arm 2311 and the second upper arm 2411 are controlled to be turned on simultaneously, forming a circuit in which the first assembled battery 211 and the energy storage module 250 charge the second assembled battery 212, with the charging current path being the positive electrode of the first assembled battery 211 → V11 → V17 → positive electrode of the second assembled battery 212 → negative electrode of the second assembled battery 212 → inductor L1 → negative electrode of the first assembled battery 211.

[0218] As can be seen, for the specific circuit structure of a charging / discharging circuit including two or more battery packs, by designing a reasonable control timing and controlling the on / off of each arm in the charging / discharging circuits shown in Figures 12 to 15, a circuit is formed in which one of the battery packs discharges to the energy storage module 250, and a circuit in which the energy storage module 250 and this battery pack charge another battery, and the discharging circuit and the charging circuit are switched, thereby heating both batteries simultaneously during the discharging and charging processes, and achieving relatively high heating efficiency.

[0219] It should be understood that the charge / discharge circuits shown in Figures 12-15 are only schematic, and each arm in the figures may have other implementations. For example, in one preferred implementation shown in Figure 12, the first upper arm 2311 may include a switch tube V11 and a freewheeling diode D11 connected in parallel with the switch tube V11. The first lower arm 2321 may include a switch tube V12 and a freewheeling diode D12 connected in parallel with the switch tube V12. The switch module 240 includes only one switch arm, and the second upper arm 2411 of this switch arm may include a switch tube V17 and a freewheeling diode D15 connected in parallel with the switch tube V17, and the second lower arm 2412 may include a switch tube V18 and a freewheeling diode D16 connected in parallel with the switch tube V18. The embodiments of the present application are not limited to the specific form of each arm, and the function of the charge / discharge circuit can be achieved even if each arm does not include a freewheeling diode.

[0220] Freewheeling diodes are generally used in conjunction with inductors. When the inductor current changes suddenly, the voltage across the inductor changes suddenly, which can damage other elements in the circuit. However, when used in conjunction with a freewheeling diode, the inductor current changes more slowly, preventing sudden voltage changes and improving the safety of the circuit.

[0221] For example, as shown in FIG. 12, when switching from the first stage to the second stage of a heating cycle, that is, when switching between the switch tube V17 and the switch tube V18, there is a switching delay, so that a current may temporarily remain in the discharge path from the first assembled battery 211 to the inductor L1 in the first stage. At this time, the freewheeling diode D16 buffers this current, preventing a sudden voltage change and improving the safety of the circuit.

[0222] In the above embodiment with two or more battery packs, during each heating cycle, one battery pack first discharges to the energy storage module, and then this battery pack and the energy storage module together charge another battery pack. By maintaining the charging or discharging current at a stable and relatively high current value, a square wave or quasi-square wave AC current can be generated in the charging and discharging circuit, as shown in the square wave schematic diagram in Figure 16. The dual battery pack configuration effectively reduces the constraints on the magnitude and frequency of the heating current of the energy storage module. The dual battery pack heating method allows the energy of the energy storage module to be timely released to one of the batteries so that the heating current of the battery pack can be maintained at a stable and relatively high current value according to a preset heating frequency. This allows the heating rate to be significantly increased by adjusting the frequency of the heating current when the batteries are in different temperature and SOC states. Because the magnitude of the heating current can be maintained at a stable value, the AC current waveform generated in the charging and discharging circuit of the dual battery pack is a square wave or quasi-square wave.

[0223] In the embodiment of the present application, the pseudo-square wave is a waveform distorted from a regular square wave to a pseudo-square wave due to some equipment errors or issues such as current modulation accuracy. Errors that cause the distortion may include issues such as delayed equipment response time and electromagnetic interference. In each cycle of the square wave and pseudo-square wave, there is a peak discharge current that remains stable for a certain period of time and a peak charge current that remains stable for a certain period of time. Referring to the square wave shown in FIG. 16, for the pseudo-square wave, even in a single cycle of the pseudo-square wave, the current remains at I1 during the time period 0-t1 and at -I2 during the time period t1-t2, with the currents I1 and -I2 being in opposite directions. The pseudo-square wave may also include a trapezoidal wave or other waveforms that have a peak discharge current that remains stable for a certain period of time and a peak charge current that remains stable for a certain period of time.

[0224] In some other embodiments, the frequency of the charging and discharging current may be controlled by the motor controller, the frequency of the current may be reduced, and as much electrical energy stored in the energy storage module as possible may be recharged into the battery pack in each cycle, thereby generating an AC current having any one of a triangular waveform, a quasi-triangular waveform, a sine waveform, and a quasi-sine waveform in the charging and discharging circuit, as shown in FIG. 10 .

[0225] Here, the frequency of the charging / discharging current in a scenario in which a square wave or a pseudo-square wave occurs is greater than the frequency of the current in a scenario in which a waveform such as a triangular wave, a pseudo-triangular wave, a sine waveform, or a pseudo-sine waveform occurs.

[0226] In some other embodiments of the present application, the switch module 240 includes at least one pair of switch legs, each pair including a switch and a diode connected in series, the first energy storage element 251 in the energy storage module 250 includes at least one energy storage device, the number of energy storage devices is equal to the number of switch legs, and the energy storage devices are connected in one-to-one correspondence with the switch legs. The cathode of the diode in the switch leg is connected to the positive electrode of the power supply module 210, and the anode of the diode in the switch leg is connected to the negative electrode of the power supply module 210.

[0227] In this embodiment, the switch module includes a switch leg consisting of a switch and a diode connected in series. Using one diode and one switch connected in series reduces costs by half compared to using a switch arm consisting of two switch tubes, saving on switching time. Furthermore, the diode is passively controlled, eliminating the need for active control. The control strategy for a structure using one diode and one switch is simpler. Furthermore, more structural variations of the switch module are provided, and different variations of the charge / discharge switching module can be combined to create a variety of specific circuit configurations for charge / discharge circuits, thereby satisfying different user and industrial production needs for charge / discharge circuit configurations. The cathode of the diode in the switch leg is connected to the positive electrode of the power supply module. This turns off the current, preventing direct forward current flow between the positive and negative electrodes of the power supply module through the diode, thereby improving the safety of the charge / discharge circuit.

[0228] The structure of the switch module 240 in Figures 9 and 12-15 may all be replaced with the switch leg structure described above. Using Figure 9 as an example, the structure of the switch module 240 can be modified to include a switch V18 and a diode D15 connected in series, as shown in Figure 17. As another example, using Figure 9 as an example, the structures of the switch module 240 and the charge / discharge switching module 230 in Figure 9 can be modified to include a switch V18 and a diode D15 connected in series, as shown in Figure 18. The switch module 240 includes a switch V18 and a diode D15 connected in series, and the charge / discharge switching module 230 includes a switch V11 and a diode D11 connected in series. The different structural combinations of the switch module 240 and the charge / discharge switching module 230 in Figures 12-15 will not be described one by one here.

[0229] In the charging / discharging circuits of the above embodiments, the battery is not heated directly by the vehicle motor, but the battery self-heating function is realized by adding components such as the heating module 220 and the charging / discharging switching module 230. As a result, the motor can operate normally during the battery heating process, and the heating of the power battery does not affect the normal running of the vehicle equipped with the power battery.

[0230] In some other embodiments of the present application, the power battery may be heated using a motor circuit installed in the vehicle to avoid unnecessary cost increases when heating the power battery. Accordingly, the energy storage module 250 includes an M-phase motor, and the switch module 240 includes an M-phase arm, where M is a positive integer. Here, the M-phase arm, the power supply module 210, and the charge / discharge switching module 230 are connected in parallel, and the connection points of the upper and lower arms of the M-phase arm are connected in one-to-one correspondence to the M-phase windings of the M-phase motor, respectively, and the charge / discharge switching module 230 is connected to the connection point of the M-phase winding.

[0231] The power supply module 210 includes at least one battery pack, and the battery pack may be a set including multiple battery modules or a battery module including multiple battery cores. The M-phase arms included in the switch module 240 may be realized by an inverter corresponding to the motor, and each phase arm includes an upper arm and a lower arm. For example, an inverter corresponding to a three-phase motor includes three phase arms, including three upper arms and three lower arms.

[0232] To form a charge circuit or a discharge circuit in the charge / discharge circuit, the upper arm or lower arm of the M-phase arm and the first switching circuit 231 or the second switching circuit 232 of the on-charge / discharge switching module 230 need to be turned on. Assuming that the upper end of the power supply module 210 is positive and the lower end is negative, turning on the upper arm of the M-phase arm and the second switching circuit 232 forms a discharge circuit, and current flows from the positive electrode of the power supply module 210, passes through the M upper arms of the M-phase arm, and then passes through the M-phase motor, and returns to the negative electrode of the power supply module 210 via the second switching circuit 232. Turning on the lower arm of the M-phase arm and the first switching circuit 231 forms a charge circuit, and current flows from the negative electrode of the power supply module 210, passes through the M lower arms of the M-phase arm, and then passes through the M-phase motor, and then returns to the positive electrode of the power supply module 210 via the first switching circuit 231.

[0233] By periodically switching the charging and discharging circuits, current is caused to flow inside the power supply module 210, thereby generating heat and heating the power supply module 210.

[0234] In this embodiment, the M-phase motor included in the energy storage module 250 is not only connected to the M-phase arm included in the switch module 240, but also to the charge / discharge switching module 230, so that the current flowing through the M-phase arm can simultaneously flow into all windings of the M-phase motor and flow out from the other ends of all windings, so that the current flowing through all windings of the M-phase motor can be current of the same direction and magnitude rather than alternating current with different directions. This effectively reduces the problem of excessive motor vibration noise when using a motor circuit to heat a power battery.

[0235] The circuit structure of a charge / discharge circuit that uses a motor to heat a battery will be described in detail below with reference to the accompanying drawings. First, in a charge / discharge circuit that includes only one assembled battery, this assembled battery may be a single battery pack or may be configured by combining multiple battery packs. In the embodiments of this application, this assembled battery included in the charge / discharge circuit is referred to as the first assembled battery.

[0236] In the charge / discharge circuit, the power supply module 210 includes a first assembled battery 211 and a switch module 240 M-phase arm, the energy storage module 250 includes an M-phase motor, and the charge / discharge switching module 230 includes a first switching circuit 231 and a second switching circuit 232 connected in series. The first assembled battery 211, the M-phase arm, and the charge / discharge switching module 230 are connected in parallel, and the connection points of the upper and lower arms of the M-phase arm are connected in one-to-one correspondence to the M-phase windings of the M-phase motor, and the connection point of the first switching circuit 231 and the second switching circuit 232 in the charge / discharge switching module 230 is connected to the M-phase motor.

[0237] 19 , the M-phase arm is exemplified as a three-phase arm including an arm 331, an arm 332, and an arm 333. Accordingly, the M-phase motor is a three-phase winding motor including three windings, namely, a winding 311, a winding 312, and a winding 313. The first assembled battery 211, the arm 331, the arm 332, the arm 333, and the charge / discharge switching module 230 are connected in parallel. A connection point between the upper arm 3311 and the lower arm 3312 of the arm 331 is connected to one end of the winding 311, a connection point between the upper arm 3321 and the lower arm 3322 of the arm 332 is connected to one end of the winding 312, and a connection point between the upper arm 3331 and the lower arm 3332 of the arm 333 is connected to one end of the winding 313. The other end of the winding 311, the other end of the winding 312, and the other end of the winding 313 are connected to the same line, and the connection point where the winding 311, the winding 312, and the winding 313 are connected to the same line is called the neutral point. The connection point between the first switching circuit 231 and the second switching circuit 232 of the charge / discharge switching module 230 is connected to the neutral point of the motor.

[0238] 19, the charge / discharge switching module 230 has an arm structure, in which the first switching circuit 231 includes a first upper arm 2311 and the second switching circuit 232 includes a first lower arm 2321.

[0239] 19, the first assembled battery 211, the upper arms 3311 to 3331, the windings 311 to 313, and the first lower arm 2321 of the charge / discharge switching module 230 jointly form a discharge circuit. The discharge current path is from the positive electrode of the first assembled battery 211 to the upper arm 331. 3311 , upper arm 3321 of arm 332 and upper arm 3331 of arm 333 →windings 311 , 312 and 313 →first lower arm 2321 →negative electrode of first assembled battery 211 .

[0240] On the other hand, the first assembled battery 211, the lower arms 3312-3332, the windings 311-313, and the first upper arm 2311 of the charge / discharge switching module 230 jointly form a charging circuit (not shown). The charging current path is from the negative electrode of the first assembled battery 211 → the lower arm 3312 of the arm 331, the lower arm 3322 of the arm 332, and the lower arm 3332 of the arm 333 → the windings 311, 312, and 313 → the first upper arm 2311 → the positive electrode of the first assembled battery 211.

[0241] 19, the connection point of the motor windings is connected to the connection point of the first upper arm 2311 and the first lower arm 2321, allowing current to flow in from all windings simultaneously during charging or discharging, without needing to flow out through any one phase winding. The currents flowing in and out of the three-phase windings are always equal in magnitude with zero phase difference, resulting in a nearly zero stator magnetic field generated by the spatially symmetrical three-phase windings. This effectively suppresses vibration noise caused by the interaction between the stator magnetic field and the rotor magnetic field when the motor circuit is used to heat the power battery. At the same time, this prevents the motor from running, solving the problem of rotor overheating within the motor and extending the service life of the battery due to self-heating.

[0242] In one example, a second energy storage element 260 is installed between the M-phase motor and the charge / discharge switching module 230. The second energy storage element 260 may include at least one external inductor, or at least one capacitor, or at least one inductor and / or capacitor connected in series. Specifically, a connection point between the first switching circuit 231 and the second switching circuit 232 in the charge / discharge switching module 230 is connected to one end of the second energy storage element 260, and the other end of the second energy storage element 260 is connected to the neutral point of the M-phase motor.

[0243] The difference between the charging / discharging circuit shown in Fig. 20 and the circuit structure shown in Fig. 19 is that in Fig. 20, an external inductor unit 321 is installed between the neutral point of the three-phase motor and the connection point between the first upper arm 2311 and the first lower arm 2321. Optionally, the external inductor unit 321 may be a conductor, as shown in Fig. 19. Also, the embodiments of the present application do not need to limit the number of external inductor units.

[0244] A second energy storage element 260 is added between the motor winding and the charge / discharge switching module 230. The second energy storage element 260 and the motor winding jointly store energy, thereby contributing to increasing the electrical energy stored in the discharge circuit and recharging the electrical energy stored in the charging circuit to the assembled battery, thereby improving the heating efficiency of the assembled battery. In Figure 20, an external inductor unit is installed between the motor and the charge / discharge switching module 230, which increases the inductance and is beneficial to reducing the current ripple during the heating process, thereby effectively increasing the charge / discharge current and improving the charge / discharge efficiency.

[0245] Alternatively, the M-phase motor may be a six-phase winding motor, and accordingly, the M-phase winding may be all windings in the six-phase winding motor. Alternatively, the M-phase arm may be a three-phase arm or a six-phase arm.

[0246] 19 and 20 may be the structure of any one of the charge / discharge switching modules 230 shown in FIGS. 4 to 7. Specifically, in one example, the freewheeling diodes in the first upper arm 2311 and the first lower arm 2321 in FIGS. 19 and 20 may be removed, and only the switch triodes may be reserved, and the switch triodes may be replaced with other components having a switch function, such as a relay switch.

[0247] In another example, the charge / discharge switching module 230 may have a structure that does not include an arm structure but includes a diode and a switch connected in series. As shown in FIG. 21 , the charge / discharge switching module 230 includes a diode D7 and a switch tube V7 connected in series. The positive electrode of the first assembled battery 211, all upper arms of the switch module 240, and the cathode of the diode D7 are connected to the same line, while the negative electrode of the first assembled battery 211, all lower arms of the switch module 240, and one end of the switch tube V7 are connected to the same line. The connection points of the upper and lower arms of each set of arms of the switch module 240 are connected in one-to-one correspondence to the three-phase windings LA, LB, and LC of the three-phase motor. The common connection point of the three-phase windings LA, LB, and LC is connected to the connection point of the diode D7 and the switch tube V7. The anode of the diode D7 is connected to one end of the switch tube V7, and the other end of the switch tube V7 is connected to the negative electrode of the first assembled battery 211.

[0248] 21, all upper arms, switches K, and switch tubes V7 of the switch module 240 are controlled to be closed, forming a discharge circuit between all upper arms that control the first assembled battery 211 and switch module 240, windings LA, LB, and LC, switch K, inductor L, and switch tube V7, with the discharge current path being the positive electrode of the first assembled battery 211 → all upper arms that control the switch module 240 → windings LA, LB, and LC → switch K → inductor L → switch tube V7 → negative electrode of the first assembled battery 211. In addition, all lower arms and switches K that control the switch module 240 are controlled to be closed, and all upper arms and switch tubes V7 that control the switch module 240 are controlled to be cut off. Then, a charging circuit is formed between the first assembled battery 211, all the lower arms of the switch module 240, the windings LA, LB, and LC, the switch K, the inductor L, and the diode D7, and the charging current path is as follows: negative electrode of the first assembled battery 211 → all the lower arms of the switch module 240 → windings LA, LB, and LC → switch K → inductor L → diode D7 → positive electrode of the first assembled battery 211.

[0249] 21, the diode D7 may be configured in the reverse direction, i.e., the cathode of the diode D7 is connected to the switch tube V7, and the anode of the diode D7 is connected to the positive electrode of the first assembled battery 211. After the diode D7 is configured in the reverse direction, during the discharge process, the switch K and all lower arms of the switch module 240 are controlled to be closed, and all upper arms of the switch module 240 and the switch tube V7 are controlled to be cut off, forming a discharge circuit between the first assembled battery 211, the switch K, the diode D7, the inductor L, the windings LA, LB, and LC, and all lower arms of the switch module 240. The discharge current path is as follows: the positive electrode of the first assembled battery 211 → the diode D7 → the inductor L → the switch K → the windings LA, LB, and LC → all lower arms of the switch module 240 → the negative electrode of the first assembled battery 211. During the charging process, all upper arms of the switch module 240, the switch K, and the switch tube V7 are controlled to be closed, and all lower arms of the switch module 240 are controlled to be cut off, forming a charging circuit between the first assembled battery 211, all upper arms of the switch module 240, the windings LA, LB, and LC, the switch K, the inductor L, and the switch tube V7, and the charging current path is as follows: negative electrode of the first assembled battery 211 → switch tube V7 → inductor L → switch K → windings LA, LB, and LC → all upper arms of the switch module 240 → positive electrode of the first assembled battery 211.

[0250] 21, only one of the switch K and the inductor L may be provided. Alternatively, the switch K and the inductor L may not be provided, and the neutral points of the windings LA, LB, and LC may be connected to the charge / discharge switching module 230 by conductors.

[0251] In the circuit structure shown in Figure 21, the charge / discharge switching module 230 only uses one freewheeling diode and one triode, which reduces the cost by half compared to using two switch tubes and saves the cost of the switching period. And the diode D7 is passively controlled, does not need active control, and the control strategy is simpler.

[0252] The circuit structure in FIG. 21 may be modified to the circuit structure shown in FIG. 20. The difference between FIG. 22 and FIG. 21 is that a switch K is installed between the cathode of diode D7 and the connection point of the switch module 240. In FIG. 22, the upper arm of the switch module 240 and the switch tube V7 are controlled to close, forming a discharge circuit between all upper arms controlling the first assembled battery 211 and the switch module 240, the windings LA, LB, and LC, the inductor L, and the switch tube V7. The discharge current path is as follows: the positive electrode of the first assembled battery 211 → all upper arms controlling the switch module 240 → the windings LA, LB, and LC → the inductor L → the switch tube V7 → the negative electrode of the first assembled battery 211. In addition, all lower arms controlling the switch module 240 and the switch K are closed, and all upper arms controlling the switch module 240 and the switch tube V7 are controlled to be cut off. Then, a charging circuit is formed between the first assembled battery 211, all the lower arms of the switch module 240, the windings LA, LB, and LC, the inductor L, the diode D7, and the switch K, and the charging current path is as follows: negative electrode of the first assembled battery 211 → all the lower arms of the switch module 240 → windings LA, LB, and LC → inductor L → diode D7 → switch K → positive electrode of the first assembled battery 211.

[0253] The direction of diode D7 in Figure 22 may be reversed. That is, the anode of diode D7 is connected to switch K, and the cathode of diode D7 is connected to switch tube V7. After diode D7 is reversed, during the discharge process, switch K and all lower arms of switch module 240 are closed, and all upper arms of switch module 240 and switch tube V7 are controlled to be cut off. This forms a discharge circuit between the first assembled battery 211, switch K, diode D7, inductor L, windings LA, LB, and LC, and all lower arms of switch module 240. The discharge current path is as follows: positive electrode of first assembled battery 211 → switch K → diode D7 → inductor L → windings LA, LB, and LC → all lower arms of switch module 240 → negative electrode of first assembled battery 211. During the charging process, all upper arms and switch tubes V7 of the switch module 240 are controlled to be closed, and all lower arms and switches K of the switch module 240 are controlled to be disconnected, forming a charging circuit between the first assembled battery 211, all upper arms of the switch module 240, windings LA, LB, and LC, inductor L, and switch tube V7. The charging current path is as follows: negative electrode of the first assembled battery 211 → switch tube V7 → inductor L → windings LA, LB, and LC → all upper arms of the switch module 240 → positive electrode of the first assembled battery 211.

[0254] In FIG. 22, the switch K is installed between the diode D7 and the positive electrode of the first assembled battery 211. When the charge / discharge switching module 230 fails, the switch K is turned off to prevent damage to other devices in the circuit due to the failure of the charge / discharge switching module 230.

[0255] The circuit structure in FIG. 19 may be modified to the circuit structure shown in FIG. 23. The difference between FIG. 23 and FIG. 21 is that the positions of the diode D7 and the switch tube V7 are swapped. In FIG. 23, the switch tube V7 is connected to the positive electrode of the first assembled battery 211, and the diode D7 is connected to the negative electrode of the first assembled battery 211. In the circuit structure shown in FIG. 23, all lower arms of the switch module 240, the switch K, and the switch tube V7 are controlled to be closed, forming a discharge circuit between the first assembled battery 211, all lower arms controlling the switch module 240, the windings LA, LB, and LC, the switch K, the inductor L, and the switch tube V7. The discharge current path is as follows: the positive electrode of the first assembled battery 211 → the switch tube V7 → the inductor L → the switch K → the windings LA, LB, and LC → all lower arms controlling the switch module 240 → the negative electrode of the first assembled battery 211. In addition, all upper arms and switch K that control the switch module 240 are closed, and all lower arms and switch tube V7 that control the switch module 240 are controlled to be cut off. This forms a charging circuit between the first assembled battery 211, all upper arms of the switch module 240, windings LA, LB, and LC, switch K, inductor L, and diode D7, and the charging current path is as follows: negative electrode of first assembled battery 211 → diode D7 → inductor L → switch K → windings LA, LB, and LC → all upper arms of the switch module 240 → positive electrode of the first assembled battery 211.

[0256] 23, the direction of the diode D7 may be reversed, i.e., the anode of the diode D7 may be connected to the switch tube V7, and the cathode of the diode D7 may be connected to the negative electrode of the first assembled battery 211. The control method may be adjusted accordingly, and no further explanation will be given here.

[0257] 23, only one of the switch K and the inductor L may be provided. Alternatively, the switch K and the inductor L may not be provided, and the neutral points of the windings LA, LB, and LC may be connected to the charge / discharge switching module 230 by conductors.

[0258] In the circuit structure shown in Figure 23, the charge / discharge switching module 230 only uses one freewheeling diode and one triode, which reduces the cost by half compared to using two switch tubes and saves the cost of the switching period. And the diode D7 is passively controlled, does not need active control, and the control strategy is simpler.

[0259] The circuit structure in FIG. 23 may be modified to the circuit structure shown in FIG. 24. The difference between FIG. 24 and FIG. 23 is that a switch K is installed between the diode D7 and the negative electrode of the first assembled battery 211. In the circuit structure shown in FIG. 24, all lower arms of the switch module 240 and the switch tube V7 are controlled to be closed, forming a discharge circuit between the first assembled battery 211, all lower arms controlling the switch module 240, the windings LA, LB, and LC, the inductor L, and the switch tube V7. The discharge current path is from the positive electrode of the first assembled battery 211 to the switch tube V7 to the inductor L to the windings LA, LB, and LC to all lower arms controlling the switch module 240 to the negative electrode of the first assembled battery 211. In addition, all upper arms controlling the switch module 240 and the switch K are closed, and all lower arms controlling the switch module 240 and the switch tube V7 are controlled to be cut off. Then, a charging circuit is formed between the first assembled battery 211, all the upper arms of the switch module 240, the windings LA, LB, and LC, the switch K, the inductor L, and the diode D7, and the charging current path is as follows: negative electrode of the first assembled battery 211 → switch K → diode D7 → inductor L → windings LA, LB, and LC → all the upper arms of the switch module 240 → positive electrode of the first assembled battery 211.

[0260] In Figure 24, the direction of diode D7 can be reversed, i.e., the anode of diode D7 is connected to switch tube V7, and the cathode of diode D7 is connected to switch K. The control method can be adjusted accordingly, and will not be further described here.

[0261] In FIG. 24, a switch K is installed between the diode D7 and the negative electrode of the first assembled battery 211. When the charge / discharge switching module 230 fails, the switch K is turned off to prevent damage to other devices in the circuit due to the failure of the charge / discharge switching module 230.

[0262] The above embodiments all use one motor to heat the battery. In actual application scenarios, electric vehicles may have two motors, and both motors may be used to heat the power battery. For power consumption devices with two motors, two motors may be used to heat the assembled battery, with one motor's inverter corresponding to the switching module and the other motor's inverter corresponding to the charge / discharge switching module. The windings of the two motors correspond to the energy storage module. By controlling the on / off of each arm of the inverters of the two motors, the charge and discharge circuits are alternately switched between the charge and discharge circuits in the charge / discharge circuit. Figures 25 and 26 show the circuit structure of a charge / discharge circuit using two motors to heat the battery according to an embodiment of the present application.

[0263] In one example, the M-phase motor is a twin motor including a first M-phase motor and a second M-phase motor, and a connection point of the M-phase winding of the first M-phase motor is connected to a connection point of the M-phase winding of the second M-phase motor. Specifically, the first M-phase motor and the second M-phase motor may both be three-phase winding motors, and the first M-phase motor includes windings 311, 312, and 313, and the second M-phase motor includes windings 321, 322, and 323. A common connection point of windings 311, 312, and 313 is connected to a common connection point of windings 321, 322, and 323.

[0264] In a circuit structure including a twin motor, connection points of the upper and lower arms of the M-phase arms included in switch module 240 are connected in one-to-one correspondence to the M-phase windings of the first M-phase motor. Specifically, the M-phase arms in switch module 240 include arm 331, arm 332, and arm 333. Specifically, a connection point between upper arm 3311 and lower arm 3312 of arm 331 is connected to one end of winding 311, a connection point between upper arm 3321 and lower arm 3322 of arm 332 is connected to one end of winding 312, and a connection point between upper arm 3331 and lower arm 3332 of arm 333 is connected to one end of winding 313.

[0265] In the circuit structure including the twin motor, the charge / discharge switching module 230 also includes an M-phase arm, and the connection points of the upper and lower arms of the M-phase arm are connected in one-to-one correspondence to the M-phase windings of the second M-phase motor. Specifically, the charge / discharge switching module 230 includes an arm 341, an arm 342, and an arm 343. The connection point between the upper arm 3411 and the lower arm 3412 of the arm 341 is connected to one end of the winding 321, the connection point between the upper arm 3421 and the lower arm 3422 of the arm 342 is connected to one end of the winding 322, the connection point between the upper arm 3431 and the lower arm 3432 of the arm 343 is connected to one end of the winding 323, and a common connection point of the other end of the winding 311, the other end of the winding 312, the other end of the winding 313, the other end of the winding 321, the other end of the winding 322, and the other end of the winding 323 is connected.

[0266] As shown in Fig. 25, the power supply module 210, the upper arms 3311, 3321, and 3331, the windings 311 to 313, the windings 321 to 323, and the lower arms 3412, 3422, and 3432 collectively form a discharge circuit. As shown in Fig. 26, the power supply module 210, the lower arms 3312, 3322, and 3332, the windings 311 to 313, the windings 321 to 323, and the upper arms 3411, 3421, and 3431 collectively form a charge circuit. Here, the charge circuit and the discharge circuit are turned on alternately and periodically under the control of a control module (not shown).

[0267] In another implementation method, the upper arm of the M-phase arm of the charge / discharge switching module 230 and the lower arm of the M-phase arm of the switch module may be controlled to be on, thereby forming a discharge circuit between the power supply module 210, the lower arms of the M-phase arms of the switch module 240, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the charge / discharge switching module. In the circuit structure shown in Fig. 25 or 22, the lower arms 3312, 3322, 3332 and the upper arms 3411, 3421, 3431 are all controlled to be on, thereby forming a discharge circuit between the first assembled battery 211, the upper arms 3411, 3421, 3431, the windings 321-323, the windings 311-313, and the lower arms 3312, 3322, 3332.

[0268] Furthermore, the upper arm of the M-phase arm of the switch module 240 and the lower arm of the M-phase arm of the charge / discharge switching module 230 are controlled to be on, and the power supply module 210, the lower arm of the M-phase arm of the charge / discharge switching module 230, the first M-phase motor, the second M-phase motor, and the switch module 240 25 or 22 controls upper arms 3311, 3321, 3331 and lower arms 3412, 3422, 3432 to be on, and forms a charging circuit between first assembled battery 211, lower arms 3412, 3422, 3432, windings 321-323, windings 311-313, and upper arms 3311, 3321, 3331.

[0269] In the embodiment shown in Figures 25 and 26, by controlling the currents flowing into windings 311-313 to be equal in magnitude and in phase, vibration noise of the first motor can be effectively suppressed when using the motor circuit to heat the power battery. Similarly, by controlling the currents flowing out of windings 321-323 to be equal in magnitude and in phase, vibration noise of the second motor can be effectively suppressed when using the motor circuit to heat the power battery. At the same time, by preventing the motor from operating, the problem of rotor heat generation in the motor can be solved, thereby extending the operating time of the battery due to self-heating.

[0270] Alternatively, the first M-phase motor may be a six-phase motor and the second M-phase motor may be a three-phase motor, with the energy storage module 250 being all windings in the six-phase motor and the second energy storage element 260 being all windings in the three-phase motor.

[0271] Alternatively, the first M-phase motor may be a three-phase motor, the second M-phase motor may be a six-phase motor, the energy storage module 250 may be all windings in the three-phase motor, and the second energy storage element 260 may be all windings in the six-phase motor.

[0272] Optionally, the first M-phase motor is a six-phase motor, the second M-phase motor is a six-phase motor, the energy storage module 250 is all windings in the six-phase motor, and the energy storage module 250 is all windings in another six-phase motor.

[0273] The first M-phase motor and the second M-phase motor may be combined with other phase motors, and the embodiments of the present application are not limited thereto.

[0274] In some other embodiments of the present application, two or more battery packs may be included in a charge / discharge circuit that uses a motor to heat the battery. Figure 27 shows a schematic block diagram of a charge / discharge circuit that includes two or more battery packs.

[0275] As shown in FIG. 27, the charge / discharge circuit includes a power supply module 210, a switch module 240, an energy storage module 250, and a charge / discharge switching module 230.

[0276] Specifically, the power supply module 210 includes a first assembled battery 211 and a second assembled battery 212. A tenth switch (not shown, dotted lines indicate a variable connection) is connected between the first assembled battery 211 and the second assembled battery 212, and the connection between the first assembled battery 211 and the second assembled battery 212 is changed by opening or closing the tenth switch. Specifically, when the tenth switch is closed, the first assembled battery 211 and the second assembled battery 212 are connected in parallel, and when the tenth switch is disconnected, the first assembled battery 211 and the second assembled battery 212 are connected in series. The assembled battery may be a set including multiple battery modules or a battery module including multiple battery cores. The switch module 240 may be realized by an inverter and includes M-phase arms, where M is a positive integer, and each phase arm includes an upper arm and a lower arm. For example, a three-phase arm may include three upper arms and three lower arms. The energy storage module 250 may include an M-phase motor, for example, a three-phase winding motor having three-phase windings. The charge / discharge switching module 230 includes a first switching circuit 231 and a second switching circuit 232. In a charge / discharge circuit including a dual assembled battery, the first switching circuit 231 includes a first upper arm 2311, and the second switching circuit 232 includes a first lower arm 2321. The first upper arm 2311 and the first lower arm 2321 may be configured as a triode and a freewheeling diode connected in parallel, or may include only a switch.

[0277] 28 , the first assembled battery 211 and the M-phase arm included in the switch module 240 are connected in parallel, with a first end of the first assembled battery 211 and the upper arm of the M-phase arm connected to the same line. The connection points of the upper and lower arms of the M-phase arm are connected to M-phase windings of the M-phase motor in a one-to-one correspondence, and the connection point of the upper and lower arms of the charge / discharge switching module 230 is connected to the neutral point of the M-phase motor. The connection points of the upper and lower arms of the charge / discharge switching module 230 may be directly connected to the neutral point of the M-phase motor by conductors. A second energy storage element 260 may be connected between the connection points of the upper and lower arms of the charge / discharge switching module 230 and the neutral point of the M-phase motor. The second energy storage element 260 may include at least one inductor, or may include an inductor and a capacitor connected in series. A ninth switch may be installed between the connection points of the upper and lower arms of the charge / discharge switching module 230 and the neutral point of the M-phase motor.

[0278] A first end of the second assembled battery 212 and a first upper arm 2311 of the charge / discharge switching module 230 are connected to the same line, a second end of the second assembled battery 212, a second end of the first assembled battery 211, the M-phase arm, and a first lower arm 2321 of the charge / discharge switching module 230 are connected to the same line, and a tenth switch K4 is installed between the first end of the first assembled battery 211 and the first end of the second assembled battery 212.

[0279] Specifically, the M-phase arm may be a three-phase arm including arm 431, arm 432, and arm 433, and accordingly, the M-phase motor is a three-phase winding motor including three phase windings, i.e., winding 411, winding 412, and winding 413, respectively.

[0280] When it is necessary to heat the power supply module 210 using the motor, the tenth switch K4 is turned off, and at this time the first assembled battery 211 and the second assembled battery 212 are connected in series. By controlling the upper arm or the lower arm of the M-phase arm and the first upper arm 2311 and the first lower arm 2321 of the charge / discharge switching module 230, second This allows for charge / discharge control of the battery pack 212. In a first cycle, the first battery pack 211 discharges and the second battery pack 212 charges. At this time, the discharge current of the first battery pack 211 flows out from its positive electrode, passes through upper arms 4311, 4321, and 4331 of arms 431 to 433, enters windings 411 to 413, passes through the first upper arm 2311 of the charging voltage switching module 230, enters the positive electrode of the second battery pack 212, and flows out from the negative electrode of the second battery pack 212, and finally returns to the negative electrode of the first battery pack 211.

[0281] 29 , in the second cycle, the first assembled battery 211 is charged and the second assembled battery 212 is discharged. At this time, the discharge current of the second assembled battery 212 flows out from its positive electrode, passes through the first upper arm 2311 of the charge / discharge switching module 230 and enters the windings 411 to 413, passes through the upper arms 4311, 4321, and 4331 of the arms 431 to 433 and enters the positive electrode of the first assembled battery 211, flows out from the negative electrode of the first assembled battery 211, and finally returns to the negative electrode of the second assembled battery 212.

[0282] In this embodiment, the dual battery pack design effectively reduces the motor inductance constraints on the magnitude and frequency of the heating current. The dual battery heating method allows the energy of the energy storage module to be released to one of the batteries in a timely manner, and the battery heating current can be maintained at a stable magnitude according to the preset heating frequency, i.e., a square wave or quasi-square wave AC current can be generated in the charge / discharge circuit. This allows the heating rate to be significantly increased by adjusting the frequency of the heating current when the battery is at different temperatures and SOC states.

[0283] FIG. 30 shows the circuit structure of a charge / discharge circuit that uses a twin motor to heat a dual battery pack, that is, the circuit topology when the M motor is a twin motor.

[0284] 30 , the M-phase motor is a twin motor including a first M-phase motor and a second M-phase motor, and a connection point of the M-phase winding of the first M-phase motor is connected to a connection point of the M-phase winding of the second M-phase motor. Specifically, both the first M-phase motor and the second M-phase motor may be three-phase winding motors, and the first M-phase motor includes windings 411, 412, and 413, and the second M-phase motor includes windings 441, 442, and 443. A common connection point of windings 411, 412, and 413 is connected to a common connection point of windings 441, 442, and 443.

[0285] The connection points of the upper and lower arms of the M-phase arms included in switch module 240 are connected in one-to-one correspondence to the M-phase windings of the first M-phase motor. Specifically, the M-phase arms in switch module 240 include arm 431, arm 432, and arm 433. Specifically, the connection point between upper arm 4311 and lower arm 4312 of arm 431 is connected to one end of winding 411, the connection point between upper arm 4321 and lower arm 4322 of arm 432 is connected to one end of winding 412, and the connection point between upper arm 4331 and lower arm 4332 of arm 433 is connected to one end of winding 413.

[0286] The charge / discharge switching module 230 also includes an M-phase arm, and connection points of the upper and lower arms of the M-phase arm are connected to the M-phase windings of the second M-phase motor in a one-to-one correspondence. Specifically, the charge / discharge switching module 230 includes an arm 421, an arm 422, and an arm 423. A connection point between an upper arm 4211 and a lower arm 4212 of the arm 421 is connected to one end of a winding 441, a connection point between an upper arm 4221 and a lower arm 4222 of the arm 422 is connected to one end of a winding 442, a connection point between an upper arm 4231 and a lower arm 4232 of the arm 423 is connected to one end of a winding 443, and a common connection point of the other end of the winding 441, the other end of the winding 442, the other end of the winding 443, the other end of the winding 411, the other end of the winding 412, and the other end of the winding 413 is connected.

[0287] In the embodiment of Figure 30, by controlling the currents flowing into windings 411-413 to be equal in magnitude and in phase, vibration noise of the first motor can be effectively suppressed in the process of using the motor circuit to heat the power battery. Similarly, by controlling the currents flowing out of windings 441-443 to be equal in magnitude and in phase, vibration noise of the second motor can be effectively suppressed in the process of using the motor circuit to heat the power battery. At the same time, the motor can be prevented from running, solving the problem of rotor heat generation in the motor and thereby extending the service life of the battery due to self-heating.

[0288] 31 shows a schematic block diagram of a charging / discharging system 500 according to an embodiment of the present application. The charging / discharging system 500 includes a control module 530 and the charging / discharging circuit 200 according to any one of the above embodiments.

[0289] The control module 530 is used to send commands to the charging / discharging circuit 200 and control the power supply module 210 to perform charging / discharging. As shown in Fig. 31 , the charging / discharging circuit 200 includes the power supply module 210, a switch module 240, an energy storage module 250, and a charging / discharging switching module 230. The control module 530 is connected to the switch module 240 and the charging / discharging switching module 230, and is used to send a charging / discharging enable signal to the switch module 240 and the charging / discharging switching module 230 and control the on / off of the switch module 240 and the charging / discharging switching module 230, thereby forming a charging circuit or a discharging circuit that alternates in the charging / discharging circuit 200.

[0290] In one example, the control module 530 may include a complete vehicle controller or vehicle control unit (VCU) and / or a motor controller.

[0291] In one example, the power supply module 210 is a power battery.

[0292] When the charging / discharging system 500 is used to heat the power supply module 210, the control module 530 sends an enable signal to the switch module 240 and the charge / discharge switching module 230 to control the on / off of the switch module 240 and the charge / discharge switching module 230 in the charging / discharging circuit, thereby forming a charging circuit or a discharging circuit.

[0293] When the charging / discharging circuit includes only one battery pack, the switch module 240 includes at least one set of switch arms, and the charge / discharge switching module 230 includes a first switching circuit 231 and a second switching circuit 232. In response to an enable signal sent from the control module 530, the switch module 240 turns on the upper arm or the lower arm of each set of switch arms, and turns on the first switching circuit 231 or the second switching circuit 232 of the charge / discharge switching module 230 to form a charging circuit or a discharging circuit, repeatedly switching between the charging circuit and the discharging circuit, charging and discharging the power supply module 210, and thereby using the heat generated when a current flows inside the power supply module 210 for heating.

[0294] If the charging / discharging circuit includes at least two assembled batteries, in response to an enable signal sent from the control module 530, each By turning on the upper arm or the lower arm of the set of switch arms, the first switching circuit 231 or the second switching circuit 232 of the charge / discharge switching module 230 is turned on to form a charging circuit or a discharging circuit, and the first assembled battery or the second assembled battery is charged or discharged through the charging circuit or the discharging circuit, where the charging / discharging includes switching the charging / discharging states of the first assembled battery and the second assembled battery, and the charging / discharging states include charging the first assembled battery and discharging the second assembled battery, or discharging the first assembled battery and charging the second assembled battery.

[0295] In one example, the control module 530 is used to determine the state of charge (SOC) of the power battery. The state of charge (SOC) is the ratio of the remaining energy of a battery to its rated capacity under the same conditions at a certain discharge rate. The SOC is one of the important parameters of the battery management system and is also the basis for the overall charge / discharge control policy and battery balancing operation of the vehicle. However, due to the complex structure of the lithium battery itself, its state of charge cannot be obtained by direct measurement. Instead, the SOC can only be estimated using related characteristic curves or calculation formulas based on several external characteristics of the battery, such as related parameters such as the battery's internal resistance, temperature, and current.

[0296] In one example, the control module 530 is also used to receive a heating request sent from the battery management system BMS to indicate that the power battery meets the heating requirement.

[0297] In one example, by receiving a heating request sent from a Battery Management System (BMS), the control module 530 can heat the power battery in a timely manner to avoid affecting the use of a power device such as a vehicle.

[0298] In one example, the control module 530 is also used to send a heating stop signal to the switch module 240 and the charge / discharge switching module 230 when the temperature of the power battery reaches a preset temperature or when the temperature rise of the power battery becomes abnormal, so that the charging circuit or the discharging circuit is cut off, thereby stopping the heating of the power battery.

[0299] In one example, when the complete vehicle controller receives a heating request sent from the BMS, the complete vehicle controller may send a control signal to the motor controller to instruct heating of the power battery, that is, the control signal is used to instruct the motor controller to send an enable signal to the switch module 240 and the charge / discharge switching module 230 so as to cause the charging circuit to form a charging circuit or a discharging circuit.

[0300] In this embodiment, the system uses the control module 530 to control the switch module 240 and the charge / discharge switching module 230, which determines the timing of charging and discharging according to the vehicle state, ensuring that the battery can heat the power battery, and by controlling the charge / discharge currents to be equal in magnitude and phase, it can effectively suppress motor vibration noise, prevent the motor from running, and solve the problem of rotor heat generation in the motor, thereby extending the service life of the battery due to self-heating.

[0301] 32 , in some other embodiments of the present application, the charging / discharging system 500 further includes a charging device 140 connected to the charging / discharging circuit 200, and the charging device 140 is used to charge the assembled battery included in the power supply module 210 via the charging / discharging circuit 200. The charging device 140 includes, but is not limited to, a charging station, a charger, or another electric vehicle. The charging / discharging circuit 200 is connected to the charging device 140, and the charging device 140 is used to charge the power battery via the charging / discharging circuit 200.

[0302] Since the charging / discharging circuit 200 has both a heating mode and a charging mode, it can not only be used to heat the power battery, but also adjust the charging voltage during the charging process of the power battery by the charging device 140. In this way, when the voltage of the charging device 140 and the voltage of the power battery do not match, for example, when the voltage of the charging device 140 is lower or higher than the voltage of the power battery, the charging device 140 can step-up charge or step-down charge the power battery through the charging / discharging circuit 200, thereby improving the compatibility between the charging device 140 and the power battery.

[0303] For example, when the voltage of the charging device 140 is lower than the voltage of the power battery, the control module 530 controls the switch module 240 and the charge / discharge switching module 230 to form a circuit in which the charging device 140 charges the energy storage module 250, and a circuit in which the charging device 140 and the energy storage module 250 simultaneously charge the power supply module 210.

[0304] Furthermore, for example, when the voltage of the charging device 140 is higher than the voltage of the power battery, the control module 530 controls the switch module 240 and the charge / discharge switching module 230 to form a circuit in which the charging device 140 charges the power supply module 210 and the energy storage module 250, and a circuit in which the energy storage module 250 charges the power supply module 210.

[0305] In one implementation, as shown in Figure 32, the energy storage module 250 is, for example, an inductor L1, whose second end is connected to one end of the charging device 140 via a switch tube V15, and whose second end is connected to the other end of the charging device 140, which is used to charge the first assembled battery 211 via the charging / discharging circuit 200. The capacitor C3 in Figure 33 may be the capacitor of the charging device 140, which can, for example, play a role in stabilizing the voltage during the charging process.

[0306] In one implementation, the switch tube V17 may further be a mode-switching switch, where when the charging / discharging circuit 200 is in a heating mode, the control module 530 controls the switch tube V17 to close, and when the charging / discharging circuit 200 is in a charging mode, the control module 530 controls the switch tube V13 to cut off.

[0307] It should be understood that if the switch tube V17 is used as a mode-switching switch, the freewheeling diode D15 should not be connected across it. In this case, one heating cycle may only include the following process: the switch tube V12 and the switch tube V17 are simultaneously closed to form a circuit including the first assembled battery 211, the switch tube V17, the inductor L1, and the switch tube V12, so that the first assembled battery 211 discharges to the inductor L1; then the switch tube V12 and the switch tube V17 are also closed to form a circuit including the first assembled battery 211, the freewheeling diode D16, the inductor L1, and the freewheeling diode D11, so that the inductor L1 charges the first assembled battery 211. In this case, the freewheeling diode D12 does not need to be connected across the switch tube V12.

[0308] 34, a switch tube V16 may be connected as a mode switching switch between the first end of the switch module 240 and the first end of the charge / discharge switching module 230. In the heating mode, the switch tube V16 is closed, while in the charging mode, the switch tube V16 is cut off.

[0309] When the charging / discharging circuit 200 switches from the heating mode to the charging mode, the control module 530 cuts off the upper arm of the switch module 240, for example, controls the switch tube V17 or the switch tube V16 to be cut off; when the voltage of the charging device 140 is lower than the voltage of the first assembled battery 211, the control module 530 controls the switch tube V12 and the first switch tube V15 to be closed and the switch tube V11 and the switch tube V18 to be cut off, thereby forming a circuit including the charging device 140, the energy storage module 250, and the second switch tube V12, so that the charging device 140 charges the energy storage module 250; and controls the switch tube V11 and the first switch tube V15 to be closed and the switch tube V12 and the switch tube V18 to be cut off, thereby forming a circuit including the charging device 140, the energy storage module 250, the switch tube V11, and the first assembled battery 211, so that the charging device 140 and the energy storage module 250 simultaneously charge the first assembled battery 211.

[0310] As can be seen, when the voltage of the charging device 140 is lower than the voltage of the first assembled battery 211, a reasonable control timing is set and each sub-arm is controlled to be turned on and off, thereby forming a first stage in each charging cycle in which the charging device 140 charges the energy storage module 250, and a second stage in which the charging device 140 and the energy storage module 250 simultaneously charge the first assembled battery 211. In this way, during the first stage in which the charging device 140 charges the energy storage module 250, a certain amount of power is stored in the energy storage module 250, so that the energy storage module 250 and the charging device 140 jointly charge the first assembled battery 211 in the second stage, thereby reducing the voltage difference between the charging device 140 and the first assembled battery 211 and improving charging efficiency.

[0311] Furthermore, when the voltage of the charging device 140 is higher than the voltage of the first assembled battery 211, the control module 530 controls the switch tube V11 and the first switch tube V15 to close and the switch tube V12 and the switch tube V18 to cut off, thereby forming a circuit including the charging device 140, the energy storage module 250, the switch tube V11, and the first assembled battery 211, so that the charging device 140 charges the first assembled battery 211 and the energy storage module 250; and controls the switch tube V11 to close and the switch tube V12, the switch tube V18, and the first switch tube V15 to cut off, thereby forming a circuit including the energy storage module 250, the switch tube V11, the first assembled battery 211, and the freewheeling diode D18, so that the energy storage module 250 charges the first assembled battery 211.

[0312] As can be seen, when the voltage of the charging device 140 is higher than the voltage of the first assembled battery 211, reasonable control timing is set and each sub-arm is controlled to be turned on and off, thereby forming a phase in each charging cycle in which the charging device 140 charges the energy storage module 250 and the first assembled battery 211, and a phase in which only the energy storage module 250 charges the first assembled battery 211. On the one hand, when the charging device 140 charges the energy storage module 250 and the first assembled battery 211, the energy storage module 250 can absorb part of the voltage, thereby appropriately reducing the voltage difference between the charging device 140 and the first assembled battery 211. On the other hand, to prevent the charging device 140 from continuously charging the first assembled battery 211 at a high voltage because the voltage of the charging device 140 is higher than that of the first assembled battery 211, the charging device 140 and the energy storage module 250 may alternately charge the first assembled battery 211. Here, when the charging device 140 charges the energy storage module 250 and the first assembled battery 211, a certain amount of power can be stored in the energy storage module 250, and the energy storage module 250 can independently charge the first assembled battery 211 based on this portion of the power.

[0313] Figures 33 and 34 are both based on the charging and discharging circuit shown in Figure 9 and connect the charging device 140. It should be understood that the charging and discharging circuits shown in Figures 12-15, 19-26 and 28-30 connect the charging device 140, and the technical effect that can be achieved by connecting the charging device 140 to the circuit structure shown in Figure 9 above can be realized.

[0314] In one implementation, as shown in Fig. 35, the first battery pack 211 is also connected to a motor driving circuit 141 to provide power to the driving circuit 141. Taking a three-phase motor as an example in Fig. 35, the driving circuit 141 is an inverter circuit that includes arms made up of switch tubes V1, V2, V3, V4, V5, and V6, and connects windings A1, B1, and C1 of the motor.

[0315] As can be seen, when the first assembled battery 211 is heated using the charging / discharging circuit, the first assembled battery 211 still provides power to the motor driving circuit 141 connected to the first assembled battery 211, thereby realizing heating of the first assembled battery 211 while driving.

[0316] Based on the above description, by installing an additional charge / discharge circuit and using this charge / discharge circuit to heat the first assembled battery 211, the motor can normally drive the vehicle and heating while driving can be achieved. Specifically, by designing a reasonable control timing and controlling each arm in the charge / discharge circuit, a circuit is formed in which the first assembled battery 211 discharges to the energy storage module 250 in the charge / discharge circuit, and a circuit in which the energy storage module 250 charges the first assembled battery 211, thereby effectively utilizing the energy storage module 250 to achieve heating for the power battery.

[0317] When the charging device 140 charges the first assembled battery 211 through the charge / discharge circuit, the charge / discharge circuit enters a charging mode. At this time, the first assembled battery 211 cannot be heated using the charge / discharge circuit, so the first assembled battery 211 can be heated using the motor drive circuit 141. Unlike a method of heating the coolant using heat generated by the motor's operating loss, in this case, the IGBTs in the drive circuit 141 can be controlled to form a charge / discharge circuit, thereby realizing heating of the first assembled battery 211. For example, when the VCU receives a heating request sent from the BMS but the charge / discharge circuit is in a charging mode, the VCU may notify the motor controller to control the motor drive circuit 141 to heat the first assembled battery 211. For example, the VCU controls the IGBTs in the drive circuit 141, i.e., the switch tubes V1 to V6, to turn on and off, thereby heating the first assembled battery 211 via the drive circuit 141.

[0318] That is, in addition to the heating mode and charging mode, the charging / discharging circuit may further have another mode, namely, a charging / heating mode. When the charging / discharging circuit is in the charging / heating mode, the charging device 140 charges the first assembled battery 211 through the charging / discharging circuit and heats the first assembled battery 211 through the motor driving circuit 141.

[0319] In one implementation, a control signal for the switch tube of each arm in the drive circuit 141 may be generated using space vector pulse width modulation (SVPWM), and the control signal may control the on / off state of the switch tube of each arm so that the current flowing into the motor winding is modulated to AC. For example, the current in the motor winding may be modulated to AC by controlling the direct-axis current component of the winding current to AC and controlling the quadrature-axis current component of the winding current to zero.

[0320] The motor controller acquires any two-phase currents i and ib collected in the three-phase connection between the drive circuit 141 and the motor, and these currents flow from the drive circuit 141 to the motor. The motor controller converts the collected currents from the abc coordinate system to the dq coordinate system and resolves them in the dq coordinate system to obtain the direct-axis component i and the quadrature-axis component iq. The quadrature-axis component iq, the direct-axis component i, the given quadrature-axis signal value i_q^*, and the given direct-axis signal value i_d^* are used to obtain the modulation signal for the switch tube that needs to be turned on. Here, the given quadrature-axis signal value i_q^* is equal to 0. In this way, the first assembled battery 211 can be charged and discharged using the motor winding energy storage.

[0321] Voltage fluctuations occur in the process of heating the first assembled battery 211 using the motor drive circuit 141. However, the presence of the charge / discharge circuit allows the voltage output from the charging device 140 to the first assembled battery 211 via the charge / discharge circuit to be dynamically adjusted in accordance with voltage fluctuations in the battery heating process, thereby reducing the impact of the battery heating process on the charging device 140.

[0322] It should be understood that the "connection" or "linkage" described in the embodiments of the present application may be a direct connection or an indirect connection, and the present application is not limited thereto. For example, the connection between the first end of the first upper arm 2311 and the first end of the second upper arm 2411 may be a direct electrical connection between the first end of the first upper arm 2311 and the first end of the second upper arm 2411, as shown in Fig. 9, or may be a connection between the first end of the first upper arm 2311 and the first end of the second upper arm 2411 via another element, such as a switch tube K4, as shown in Fig. 12.

[0323] The charging / discharging circuit including the two assembled batteries shown in FIGS. 12-15 may be connected to a motor driving circuit 141 to provide power to the driving circuit 141, thereby being used to run a motor vehicle.

[0324] In one implementation, a battery management system (BMS) of the power supply module 210 collects status information of the battery pack included in the power supply module 210, such as battery temperature, state of charge (SOC), voltage signal, current signal, etc., and determines whether the power supply module 210 needs to be heated based on the status information. If it determines that the power supply module 210 needs to be heated, the BMS may send a heating request to a vehicle control unit (VCU). The VCU determines whether to turn on heating of the battery pack included in the power supply module 210 in response to the heating request sent from the BMS.

[0325] For example, after receiving a heating request transmitted from the BMS, the VCU may determine whether to heat the battery pack included in the power supply module 210 based on the SOC of the battery pack. Here, if the amount of power in the battery pack is sufficient, i.e., the SOC is relatively high, for example, higher than a threshold, the battery pack included in the power supply module 210 may be heated.

[0326] Furthermore, for example, if the power of the battery pack included in the power supply module 210 is insufficient, i.e., the SOC is relatively low, e.g., below a certain threshold, the power battery may not be heated to reduce battery heating loss. A motor controller, e.g., a microprogrammed control unit (MCU), may determine the motor status based on information such as the motor's voltage and current, and send the information to the VCU. Therefore, if the motor is operating normally at this time, the heat generated by the motor's loss of operation can be used to heat or insulate the power supply module 210. For example, the heat generated by the motor's loss of operation while driving can be used to heat the coolant in the power supply module 210, which then heats or insulates the battery pack included in the power supply module 210.

[0327] Alternatively, when the SOC of the battery pack included in the power supply module 210 is relatively low, the battery pack included in the power supply module 210 may be heated and the length of the heating cycle may be adjusted, or the heating frequency may be adjusted.

[0328] The present application does not limit the usage scenario of the charging / discharging circuit, and the charging / discharging circuit of the embodiments of the present application may be used to heat the battery pack included in the power supply module 210 when necessary.

[0329] In the process of heating the battery pack included in the power supply module 210, the BMS can further monitor whether there is an abnormality in the temperature of the battery pack included in the power supply module 210. If there is an abnormality in the temperature of the battery pack, the BMS can transmit information about the abnormal temperature to the VCU, and the VCU controls to stop heating the battery pack included in the power supply module 210. At this time, the heat generated by the loss of motor operation can be used to heat or keep warm the battery pack included in the power supply module 210, for example, the heat generated by the loss of motor operation can be used to heat the coolant in the power supply module 210, and the coolant can then heat or keep warm the battery pack included in the power supply module 210.

[0330] In the process of heating the battery pack included in the power supply module 210, if the temperature of the battery pack included in the power supply module 210 has already met the requirement, the VCU can control to stop heating the battery pack included in the power supply module 210. At this time, the heat generated by the loss of motor operation can be used to keep the battery pack included in the power supply module 210 warm, for example, the heat generated by the loss of motor operation can be used to heat the coolant in the power supply module 210, so that the coolant can keep the battery pack included in the power supply module 210 warm.

[0331] Some other embodiments of the present application further provide a power consuming device, which includes the charging / discharging system of each of the above embodiments. The power consuming device may be a device using a power battery, such as an automobile, a ship, or an aircraft. When the power consuming device is in a low-temperature environment, the power battery in the power consuming device will have a significantly reduced discharge capacity due to its low temperature, and the power battery cannot be charged in a low-temperature environment, affecting the normal use of the power consuming device in a low-temperature environment. In the power consuming device of the embodiments of the present application, the power battery is heated through a charging / discharging circuit, forming a charging circuit and a discharging circuit that alternate between the charging / discharging circuit, thereby generating an AC current in the charging / discharging circuit. This AC current flows through the power battery, generating heat in the internal resistance of the power battery, thereby heating the power battery.

[0332] The above describes in detail the circuit structure of the charge / discharge circuit and the charge / discharge system including this circuit structure in the embodiments of the present application. The following describes in detail the charge / discharge control method in the embodiments of the present application with reference to the drawings. The technical features described in the above device embodiments are all applicable to the following method embodiments.

[0333] The execution body of this charge / discharge control method is a control module, where the control module may include a VCU or an MCU or a domain controller, or may include a BMS, a VCU, and an MCU, which cooperate to execute this charge / discharge control method. In this application, the complete process of this charge / discharge control method will be described in detail using the cooperation of the BMS, the VCU, and the MCU as an example.

[0334] Here, the motor controller MCU directly controls the switch module and the charge / discharge switching module in the charge / discharge circuit. When the BMS or VCU determines that the battery pack needs to be heated, the BMS or VCU may send a control command to the MCU to indicate that the battery pack meets a heating condition, which may include the temperature of the battery pack being lower than a certain threshold and the state of charge value SOC of the battery pack being higher than a certain charging threshold. After receiving the control command sent from the BMS or VCU, the MCU sends a charge / discharge enable signal to the switch module and the charge / discharge switching module in the charge / discharge circuit.

[0335] The control module sends a charge / discharge enable signal to control the charge / discharge switching module and the switch module to turn on or off, forming alternating charge and discharge circuits in the charge / discharge circuit, thereby generating an AC waveform current. The current flows through the battery pack, causing the internal resistance of the battery to heat up, thereby achieving the goal of heating the battery pack. Here, the control module includes one of a motor controller MCU, a complete vehicle controller VCU, a battery management system BMS, or a domain controller, etc.

[0336] 9 and 19-26 include only the first assembled battery. In these circuit structures, the energy storage module stores electrical energy during the discharging phase of the first assembled battery, and the energy storage module regenerates the stored electrical energy to the first assembled battery during the charging phase. Because the energy storage module needs to discharge immediately after storing a full tank of energy and cannot maintain a single stable heating current, the waveform of the AC current generated in the charging / discharging circuit including only the first assembled battery is at least one of a triangular wave, a quasi-triangular wave, a sine wave, and a quasi-sine wave.

[0337] In this embodiment of the method, the control module may alternately send a charge enable signal and a discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency to control the switching between the charge circuit and the discharge circuit, and by controlling the frequency of switching between the charge circuit and the discharge circuit, the frequency of the AC current generated in the entire circuit can be adjusted to improve the heating rate of the battery pack.

[0338] Specifically, the control module may start timing when transmitting the discharge enable signal, and transmit the charge enable signal after a predetermined time has elapsed. Then, the control module starts timing when transmitting the charge enable signal, and retransmits the discharge enable signal after a predetermined time has elapsed, repeatedly transmitting the discharge enable signal and the charge enable signal in sequence.

[0339] The charge / discharge switching module includes a first switching circuit and a second switching circuit connected in series, and the switch module includes at least one pair of switch arms, and each pair of switch arms includes an upper arm and a lower arm in the charge / discharge circuit, and the charge circuit and the discharge circuit that are alternately switched are: The battery pack includes a circuit between the upper arm of each set of switch modules, the energy storage module, the second switching circuit, and the power supply module, a circuit between the lower arm of each set of switch modules, the energy storage module, the first switching circuit, and the power supply module, and a circuit between the upper arm of each set of switch modules, the energy storage module, the second switching circuit, and the power supply module alternately, and a circuit between the lower arm of each set of switch modules, the energy storage module, the first switching circuit, and the power supply module. By alternately switching, an AC current is formed in the charge / discharge circuit, and the AC current flows through the battery pack in the power supply module, causing heat to flow through the internal resistance of the battery pack, thereby achieving the effect of self-heating of the battery pack.

[0340] In one implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit including a first upper arm, the second switching circuit including a first lower arm, and the switch module including at least one pair of switch arms. As shown in the charge / discharge circuits in Figures 9, 19, and 20, in this circuit structure, a heating cycle may include a first stage and a second stage. In the first stage, the control module sends a discharge enable signal to the switch module and the charge / discharge switching module, and the switch module and the charge / discharge switching module respond to the discharge enable signal sent from the control module by turning on the first upper arm and the lower arms of each pair of switch arms and by disconnecting the first lower arm and the upper arms of each pair of switch arms, thereby forming a discharge circuit between the power supply module, the first upper arm, the energy storage module, and the lower arms of each pair of switch arms. In the second stage, the control module sends a charge enable signal to the switch module and the charge / discharge switching module, and in response to the charge enable signal sent from the switch module and the charge / discharge switching module control module, turns on the first lower arm and the upper arm of each set of switch arms, and disconnects the first upper arm and the lower arm of each set of switch arms, thereby forming a charging circuit between the power supply module, the first lower arm, the energy storage module, and the upper arm of each set of switch arms.

[0341] In the above circuit structure, there may be other implementations for switching the charge and discharge circuits, namely, in a first stage, in response to a discharge enable signal sent from the control module, the upper arm and the first lower arm of each set of switch arms are turned on and the first upper arm and the lower arm of each set of switch arms are disconnected, thereby forming a discharge circuit between the power supply module, the upper arm of each set of switch arms, and the energy storage module and the first lower arm; in response to a charge enable signal sent from the control module, the lower arm and the first upper arm of each set of switch arms are turned on and the first lower arm and the upper arm of each set of switch arms are disconnected, thereby forming a charge circuit between the power supply module, the lower arm of each set of switch arms, and the energy storage module and the first upper arm.

[0342] In another implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit including a third diode, the second switching circuit including a fifth switch, and the switch module including at least one pair of switch arms. In the charge / discharge circuit structure shown in Figures 21 and 22, a heating cycle may include a first stage and a second stage. In the first stage, the control module sends a discharge enable signal to the switch module and the charge / discharge switching module, and the switch module and the charge / discharge switching module turn on the upper arm of each pair of switch arms and the fifth switch and turn off the lower arm of each pair of switch arms in response to the discharge enable signal sent from the control module, thereby forming a discharge circuit between the power supply module, the upper arm of each pair of switch arms, the energy storage module, and the fifth switch. In the second stage, the control module sends a charge enable signal to the switch module and the charge / discharge switching module, and in response to the charge enable signal sent from the switch module and the charge / discharge switching module control module, turns on the lower arm of each set of switch arms and cuts off the upper arm of each set of switch arms and the fifth switch, thereby forming a charging circuit between the power supply module, the lower arm of each set of switch arms, the energy storage module and the third diode.

[0343] In another implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit including a seventh switch, the second switching circuit including a fourth diode, the anode of which is connected to the negative electrode of the first assembled battery, and the switch module including at least one pair of switch arms. In the charge / discharge circuit structure shown in Figures 23 and 24, in this structure, a heating cycle includes a first stage and a second stage. In the first stage, the control module sends a discharge enable signal to the switch module and the charge / discharge switching module, and the switch module and the charge / discharge switching module turn on the seventh switch and the lower arms of each pair of switch arms and turn off the upper arms of each pair of switch arms in response to the discharge enable signal sent from the control module, thereby forming a discharge circuit between the power supply module, the seventh switch, the energy storage module, and the lower arms of each pair of switch arms. In the second stage, in response to a charging enable signal sent from the control module, the upper arm of each set of switch arms is turned on, and the seventh switch and the lower arm of each set of switch arms are turned off, forming a charging circuit between the power supply module, the fourth diode, the energy storage module, and the upper arm of each set of switch arms.

[0344] 23 and 24, the fourth diode may be configured to be reversed, i.e., the cathode of the fourth diode may be connected to the negative electrode of the first assembled battery. In this modified configuration, the heating cycle includes a first stage and a second stage. In the first stage, the control module sends a discharge enable signal to the switch module and the charge / discharge switching module. In response to the discharge enable signal sent from the control module, the switch module and the charge / discharge switching module turn on the upper arm of each set of switch arms and turn off the seventh switch and the lower arm of each set of switch arms, thereby forming a discharge circuit between the power supply module, the upper arm of each set of switch arms, the energy storage module, and the fourth diode. In the second stage, the control module sends a charging enable signal to the switch module and the charging / discharging switching module, and in response to the charging enable signal sent from the switch module and the charging / discharging switching module control module, turns on the seventh switch and the lower arm of each set of switch arms, and cuts off the upper arm of each set of switch arms, thereby forming a charging circuit between the power supply module, the lower arm of each set of switch arms, the energy storage module and the seventh switch.

[0345] In some other embodiments of the present application, the energy storage module includes a first M-phase motor and a second M-phase motor, the switch module includes an M-phase arm, the charge / discharge switching module includes an M-phase arm, the M-phase windings of the first M-phase motor are connected in one-to-one correspondence to the M-phase arms of the switch module, the M-phase windings of the second M-phase motor are connected in one-to-one correspondence to the M-phase arms of the charge / discharge switching module, and a connection point of the M-phase windings of the first M-phase motor is connected to a connection point of the M-phase windings of the second M-phase motor. As shown in Figures 25 and 26, in this circuit structure, the heating cycle may include a first stage and a second stage. In a first stage, the control module transmits a discharge enable signal to the switch module and the charge / discharge switching module, and in response to the discharge enable signal transmitted from the control module, the switch module and the charge / discharge switching module turn on the upper arm of the M-phase arm of the switch module and the lower arm of the M-phase arm of the charge / discharge switching module, thereby forming a discharge circuit between the power supply module, the upper arm of the M-phase arm of the switch module, the first M-phase motor, the second M-phase motor, and the lower arms of the M-phase arm of the charge / discharge switching module. In a second stage, the control module transmits a charge enable signal to the switch module and the charge / discharge switching module, and in response to the charge enable signal transmitted from the switch module and the charge / discharge switching module control module, turn on the upper arm of the M-phase arm of the charge / discharge switching module and the lower arm of the M-phase arm of the switch module, thereby forming a charge circuit between the power supply module, the lower arm of the M-phase arm of the switch module, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the charge / discharge switching module.

[0346] In another implementation, for the above charge / discharge circuit structure including twin motors, in a first stage, in response to a discharge enable signal sent from the control module, the upper arm of the M-phase arm of the charge / discharge switching module and the lower arm of the M-phase arm of the switch module are turned on to form a discharge circuit between the power supply module, the lower arm of the M-phase arm of the switch module, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the charge / discharge switching module. In a second stage, in response to a charge enable signal sent from the control module, the upper arm of the M-phase arm of the switch module and the lower arm of the M-phase arm of the charge / discharge switching module are turned on to form a charge circuit between the power supply module, the lower arm of the M-phase arm of the charge / discharge switching module, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the switch module.

[0347] The above describes a control method for a charge / discharge circuit including only a first assembled battery, with reference to the accompanying drawings. Below, a detailed description is given of a control process for a charge / discharge circuit including at least a first assembled battery and a second assembled battery, with reference to the accompanying drawings. The charge / discharge circuit structures shown in Figures 12-15 and 28-30 include a first assembled battery and a second assembled battery. During each heating cycle of these circuit structures, in one phase, the first assembled battery may charge the energy storage module, and the first assembled battery and the energy storage module may simultaneously charge the second assembled battery. In another phase, the second assembled battery may charge the energy storage module, and the second assembled battery and the energy storage module may simultaneously charge the first assembled battery. The dual battery configuration effectively reduces the constraints on the magnitude and frequency of the heating current of the energy storage module, and the dual battery heating method allows the battery heating current to be maintained at a stable magnitude according to the preset heating frequency, allowing the energy of the energy storage module to be released to one of the batteries in a timely manner, thereby significantly increasing the heating rate by adjusting the frequency of the heating current when the batteries are at different temperatures and SOC states. Because the magnitude of the heating current can be maintained at a stable value, the waveform of the AC current generated in the charging and discharging circuit of the dual battery pack is a square wave or a quasi-square wave.

[0348] In an embodiment of this method, the power supply module includes at least a first assembled battery and a second assembled battery, charges and discharges the first assembled battery or the second assembled battery via a charging circuit or a discharging circuit, and generates a square wave or pseudo-square wave AC current in the charging and discharging circuit, the charging and discharging including switching between a charging and discharging state of the first assembled battery and the second assembled battery, and the charging and discharging state including charging the first assembled battery and discharging the second assembled battery, or discharging the first assembled battery and charging the second assembled battery.

[0349] In an embodiment including two battery packs, as shown in Figures 12-15 and 28-30, a first end of the second battery pack is connected to a first end of the charge / discharge switching module, a second end of the second battery pack is connected to the same line as a second end of the first battery pack, a second end of the switch module, and a second end of the charge / discharge switching module, a first end of the first battery pack is connected to a first end of the switch module, and a tenth switch is connected between the first end of the first battery pack and the first end of the second battery pack. When the control module determines that the first battery pack and the second battery pack satisfy the heating condition, it controls the tenth switch to be turned off, thereby connecting the first battery pack and the second battery pack in series.

[0350] The tenth switch can control the connection method between the first assembled battery and the second assembled battery. When the tenth switch is turned off, the first assembled battery and the second assembled battery are connected in series, and when the tenth switch is closed, the first assembled battery and the second assembled battery are connected in parallel. When it is necessary to heat the first assembled battery and the second assembled battery, the tenth switch is controlled to be turned off, thereby heating the first assembled battery and the second assembled battery connected in series. When it is necessary to supply power to the outside, the tenth switch is controlled to be closed, and power is supplied to the outside by the first assembled battery and the second assembled battery connected in parallel.

[0351] In one implementation, the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit including a first upper arm and the second switching circuit including a first lower arm, the switch module including at least one pair of switch arms, one end of the energy storage module connected to the junction between the first upper arm and the first lower arm, and the other end of the energy storage module connected to the junction between the upper and lower arms of the switch arms. As shown in Figures 12, 13, 28-30, the heating cycle may include a first stage and a second stage. In the first stage, in response to a first enable signal sent from the control module, the first upper arm and the lower arms of each pair of switch arms are turned on, and the first lower arm and the upper arms of each pair of switch arms are turned off, forming a discharge circuit between the first assembled battery, the first upper arm, the energy storage module, and the lower arms of each pair of switch arms, thereby discharging the first assembled battery to the energy storage module. In a second stage, in response to a second enable signal sent from the control module, the control module turns on the first upper arm and the upper arms of each set of switch arms, and turns off the first lower arm and the lower arms of each set of switch arms, thereby forming a charging circuit between the first assembled battery, the first upper arm, the energy storage module, the upper arms of each set of switch arms, and the second assembled battery, and charging the first assembled battery and the energy storage module to the second assembled battery. Here, the control module may repeatedly turn on the upper arms or the lower arms of each set of switch arms to control the charging time of the second assembled battery.

[0352] The heating cycle may further include a third stage and a fourth stage. In the third stage, in response to a third enable signal transmitted from the control module, the control module turns on all of the first lower arm and the upper arms of each set of switch arms and shuts off all of the first upper arm and the lower arms of each set of switch arms, thereby forming a discharge circuit between the second assembled battery, the upper arms of each set of switch arms, the energy storage module, and the first lower arm, thereby discharging the second assembled battery to the energy storage module. In the fourth stage, in response to a fourth enable signal transmitted from the control module, the control module turns on all of the first upper arm and the upper arms of each set of switch arms and shuts off all of the first lower arm and the lower arms of each set of switch arms, thereby forming a charge circuit between the second assembled battery, the upper arms of each set of switch arms, the energy storage module, the first upper arm, and the first assembled battery, thereby charging the first assembled battery from the second assembled battery and the energy storage module. Here, the control module may repeatedly switch on the first upper arm or the first lower arm to control the charging time of the first assembled battery.

[0353] 12, 13, 28-30, another control method may be adopted. That is, in the first stage, in response to a first enable signal sent from the control module, the first upper arm and the upper arms of each set of switch arms are all turned on, and the first lower arm and the lower arms of each set of switch arms are turned off, so as to form a charge / discharge circuit between the first assembled battery, the upper arms of each set of switch arms and the energy storage module, and the first upper arm and the second assembled battery, so as to discharge the first assembled battery to the energy storage module, and charge the second assembled battery from the first assembled battery and the energy storage module. In the second stage, in response to a second enable signal sent from the control module, the first upper arm and the upper arms of each set of switch arms are all turned on, the first lower arm and the lower arms of each set of switch arms are disconnected, a charge / discharge circuit is formed between the first assembled battery, the first upper arm, the energy storage module, the upper arms of each set of switch arms, and the second assembled battery, the second assembled battery is discharged to the energy storage module, and the second assembled battery and the energy storage module are charged to the first assembled battery.

[0354] In another embodiment of the dual battery pack, the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit including a first upper arm and the second switching circuit including a first lower arm, the switch module including at least one pair of switch arms, a first end of the energy storage module 250 connected to a first end of the switch module, and a second end of the energy storage module 250 connected to a first end of the charge / discharge switching module. As shown in FIG. 14 , the first end of the switch module and the first end of the charge / discharge switching module may be connected to the same wire as the positive terminal of the first battery pack. In this circuit structure, the heating cycle may include a first stage and a second stage. In the first stage, in response to a first enable signal sent from the control module, the first lower arm and the upper arms of each pair of switch arms are simultaneously turned on, and the first upper arm and the lower arms of each pair of switch arms are turned off, forming a circuit in which the first battery pack is discharged to the energy storage module. In a second stage, in response to a second enable signal sent from the control module, the lower arm and the first lower arm of each set of switch arms are simultaneously turned on and the upper arm and the first upper arm of each set of switch arms are turned off, so that the first assembled battery and the energy storage module form a circuit for charging the second assembled battery.

[0355] Furthermore, the heating cycle may further include a third stage and a fourth stage. In the third stage, in response to a third enable signal sent from the control module, the first upper arm and the lower arm of each set of switch arms are simultaneously turned on and the first lower arm and the upper arm of each set of switch arms are disconnected, forming a circuit in which the second assembled battery discharges to the energy storage module. In the fourth stage, in response to a fourth enable signal sent from the control module, the first lower arm and the lower arm of each set of switch arms are simultaneously turned on and the first upper arm and the upper arm of each set of switch arms are disconnected, forming a circuit in which the second assembled battery and the energy storage module charge the first assembled battery.

[0356] An embodiment of the present application further provides a control method for a charging / discharging circuit including another dual assembled battery, in which the charging / discharging switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, the second switching circuit includes a first lower arm, the switch module includes at least one pair of switch arms, a first end of the energy storage module 250 is connected to a second end of the switch module, and the second end of the energy storage module 250 is connected to a second end of the charging / discharging switching module. As shown in Figure 15, the second end of the switch module and the second end of the charging / discharging switching module may both be connected to the same line as the negative electrode of the first assembled battery.

[0357] In this circuit structure, the heating cycle may include a first stage and a second stage. In the first stage, in response to a first enable signal sent from the control module, the first lower arm and the upper arm of each set of switch arms are simultaneously turned on and the first upper arm and the lower arm of each set of switch arms are disconnected, forming a circuit in which the second assembled battery discharges to the energy storage module. In the second stage, in response to a second enable signal sent from the control module, the upper arm and the first upper arm of each set of switch arms are simultaneously turned on and the lower arm and the first lower arm of each set of switch arms are disconnected, forming a circuit in which the second assembled battery and the energy storage module charge the first assembled battery.

[0358] The heating cycle may further include a third stage and a fourth stage. In the third stage, in response to a third enable signal sent from the control module, the first upper arm and the lower arm of each set of switch arms are simultaneously turned on and the first lower arm and the upper arm of each set of switch arms are disconnected, forming a circuit in which the first assembled battery discharges to the energy storage module. In the fourth stage, in response to a fourth enable signal sent from the control module, the first upper arm and the upper arm of each set of switch arms are simultaneously turned on and the first lower arm and the lower arm of each set of switch arms are disconnected, forming a circuit in which the first assembled battery and the energy storage module charge the second assembled battery.

[0359] The control module may transmit the first enable signal and the second enable signal to the switch module and the charge / discharge switching module at a preset frequency, or transmit the third enable signal and the fourth enable signal at a preset frequency, or transmit the first enable signal, the second enable signal, the third enable signal and the fourth enable signal at a preset frequency, thereby alternately controlling in a charge / discharge circuit including dual assembled batteries so that one assembled battery discharges to the energy storage module, and the assembled battery and the energy storage module simultaneously charge another assembled battery.

[0360] In some embodiments of the present application, a ninth switch (switch K in FIGS. 21 and 23 ) is connected between the energy storage module and the charge / discharge switching module. When the control module determines that the battery pack included in the power supply module meets the heating condition, it first controls the ninth switch to close, and then controls the switch module and the charge / discharge switching module to turn on or off, thereby alternately switching between the discharge circuit and the charge / discharge circuit. During the charging / discharging process, the control module further monitors in real time whether the battery pack included in the power supply module meets a heating stop condition, which may include, for example, that the temperature of the battery pack has reached a desired temperature or that the temperature rise of the battery pack is abnormal. When the control module determines that the battery pack meets the heating stop condition, it controls the switch module and the charge / discharge switching module to shut off the current charge circuit or discharge circuit and also controls the ninth switch to shut off.

[0361] In an embodiment of the present application, before controlling the charging / discharging circuit to heat the assembled batteries included in the power supply module, the control module first determines whether the state-of-charge value of each assembled battery in the power supply module is equal to or greater than a predetermined charging threshold, and if it determines that the state-of-charge value of each assembled battery is equal to or greater than the predetermined threshold, the control module alternately sends a charge / discharge enable signal to the charge / discharge switching module and the switch module at a predetermined frequency.

[0362] That is, the battery pack is heated only when the state of charge value of the battery pack is greater than a preset charge threshold, thereby avoiding a situation where the power amount of the battery pack is too low to support the discharge electrical energy required for heating.

[0363] Before determining whether the state-of-charge value of each battery pack in the power supply module is equal to or greater than a predetermined charging threshold, the control module must also determine whether the temperature of the power supply module is lower than a predetermined temperature threshold. When the temperature of the battery pack is lower than the predetermined temperature threshold, the discharge capacity drops significantly and the battery pack cannot be charged even in a low-temperature environment. Therefore, if it is determined that the temperature of the power supply module is lower than the predetermined temperature threshold, it is necessary to heat the battery pack in the power supply module. At this time, it must also determine whether the state-of-charge value of each battery pack in the power supply module is equal to or greater than a predetermined charging threshold. If it is determined that the state-of-charge value of each battery pack is equal to or greater than the predetermined charging threshold, it controls the charge / discharge circuit to heat the battery pack.

[0364] Here, the preset charge threshold may be the minimum charge amount required to support the discharge of the battery pack during the heating process.

[0365] In an embodiment in which the energy storage module directly uses the vehicle's own motor to participate in the heating process, the heating process may affect the normal operation of the motor and thus affect vehicle running. Therefore, in a charge / discharge circuit structure using a motor as an energy storage module, the control module further acquires the operating status of the motor before sending the charge / discharge enable signal to the switch module and the charge / discharge switching module. This operating status may be acquired by the VCU or the MCU. If the acquired operating status indicates that the motor is currently in a driving state, the control module does not initiate the heating process of the battery pack so as not to affect the normal operation of the motor. If the acquired operating status indicates that the motor is currently in a non-driving state, the control module alternately transmits the charge / discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency.

[0366] In some other embodiments of the present application, the control module further detects whether the power battery heating system has failed, and when the motor is in a non-driving state and the power battery heating system has not failed, sends a charge / discharge enable signal to the switch module and the charge / discharge switching module.

[0367] It should be noted that in the embodiment of the present application, a failure in the battery heating system refers to a failure occurring in any one of the motor, the motor controller, the switch module, and the heat conduction circuit, etc. Meanwhile, a failure occurring in the heat conduction circuit includes, but is not limited to, problems such as a broken interconnection valve, a lack of medium in the heat conduction circuit, etc.

[0368] Alternatively, shift position information and motor rotation speed information may be acquired, and based on this, it may be determined whether the motor is in a driven state or a non-driven state. Specifically, if it is determined that the current shift position is in the P range and the vehicle speed is 0, this indicates that the motor is in a non-driven state, and if it is determined that the current shift position is not in the P range or the vehicle speed is not 0, this indicates that the motor is in a driven state.

[0369] The system determines whether the vehicle is in a normal running state based on the shift position information and motor rotation speed information, and if any of the conditions is not met, it does not send a charge / discharge enable signal to the switch module and the charge / discharge switching module, preventing the power battery from heating up and further affecting vehicle performance.

[0370] In a charging / discharging circuit that does not use the motor installed in a vehicle for heating, heating of the battery pack does not affect the normal operation of the motor, so the battery pack can be heated both when the vehicle is stationary and when the vehicle is running.

[0371] In some embodiments of the present application, the control module is a motor controller MCU, and when the vehicle controller VCU detects that the battery pack needs to be heated, the vehicle controller sends a control signal to the MCU. SendThe MCU receives a control signal sent from the vehicle controller, analyzes the control signal, and if the control signal determines that the power supply module is to be heated, the control module alternately sends a charge / discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency.

[0372] In some other embodiments, the control module is a vehicle controller VCU or a motor controller MCU. When the battery management system BMS detects that the battery pack needs to be heated and that the heating condition is met, it sends request data to the VCU. The VCU receives the request data. If the request data indicates that only the power supply module meets the heating condition, the VCU sends a control command to the MCU to activate heating only. After receiving the control command, the MCU alternately sends a charge / discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency.

[0373] Alternatively, when the BMS detects that the battery pack needs to be heated and the heating condition is met, the battery management system directly sends request data to the MCU. The MCU receives the request data sent from the battery management system, analyzes the request data, and if it determines that the request data indicates that the power supply module meets the heating condition, sends a charge / discharge enable signal alternately to the charge / discharge switching module and the switch module at a preset frequency.

[0374] In any one of the above embodiments, during the heating of the battery packs included in the power supply module, the control module further monitors the status of each battery pack in real time to determine whether the temperature of each battery pack included in the power supply module satisfies a heating stop condition, which includes whether the battery pack has reached a preset temperature or an abnormal temperature rise of the battery pack. If it determines that the temperature of the battery pack satisfies the heating stop condition, the control module sends a heating stop signal to the charge / discharge switching module and the switch module, which triggers the charge / discharge switching module and the switch module to shut off the current charge / discharge circuit. This stops the heating process in a timely manner when the temperature of the battery pack rises to the preset temperature or an abnormal temperature rise of any one of the battery packs occurs, thereby preventing damage to the battery pack or other devices in the charge / discharge circuit due to continued heating.

[0375] In some other embodiments of the present application, the charging / discharging system further includes a charging device. As shown in Figures 33-35, in addition to the circuit structures shown in these figures, a charging device may be connected to any of the charging / discharging circuits in the other embodiments described above, and this charging device is used to charge the battery pack included in the power supply module via the charging / discharging circuit.

[0376] The charging device may be a charging station, a charger, or another electric vehicle. In the charging circuit between the charging device and the power supply module, the output voltage of the charging device may not match the required voltage of the battery pack of the power supply module, and the voltage of the charging device may be higher or lower than the required voltage of the battery pack. Based on this, the embodiment of the present application may utilize a charging / discharging circuit to adjust the charging voltage between the charging device and the battery pack.

[0377] Specifically, when the voltage of the charging device is lower than the voltage of the power supply module, the switch module and the charge / discharge switching module are controlled to form a circuit in which the charging device charges the energy storage module and a circuit in which the charging device and the energy storage module simultaneously charge the power supply module.When the voltage of the charging device is higher than the voltage of the power supply module, the switch module and the charge / discharge switching module are controlled to form a circuit in which the charging device charges the power supply module and the energy storage module and a circuit in which the energy storage module charges the power supply module.

[0378] As shown in Figures 33-35, the end connected to the energy storage module and the switch module is connected to one end of a charging device through a first switch tube, and the second end of the switch module is connected to the other end of the charging device. The second end of the switch module may be connected to the negative electrode of the first assembled battery. The charging device is used to charge the power supply module through the heating module, and the heating module includes a switch module and an energy storage module. The switch module includes at least one switch arm, and the charge / discharge switching module includes a first switching circuit and a second switching circuit.

[0379] Based on the above connection structure of the charging device and the charging / discharging circuit, the control module controls the upper arms of each pair of switch arms to be disconnected. When the voltage of the charging device is lower than the voltage of the power supply module, in a first stage, the control module controls the second switching circuit and the first switch tube to be turned on and the first switching circuit to be disconnected from the lower arms of each pair of switch arms, forming a circuit including the charging device, the energy storage module, and the second switching circuit, and used by the charging device to charge the energy storage module. In a second stage, the control module controls the first switching circuit and the first switch tube to be turned on and the second switching circuit to be disconnected from the lower arms of each pair of switch arms, forming a circuit including the charging device, the energy storage module, the first switching circuit, and the power supply module, and used by the charging device and the energy storage module to simultaneously charge the power supply module.

[0380] In one implementation, the switch module includes a switch and a diode connected in parallel to the lower arm of each pair of switch arms. When the voltage of the charging device is higher than the voltage of the power supply module, in a first phase, the control module controls the first switching circuit and the first switch tube to close and the second switching circuit and the lower arm of each pair of switch arms to disconnect, forming a circuit including the charging device, the energy storage module, the first switching circuit, and the power supply module, and the charging device is used to charge the power supply module and the energy storage module. In a second phase, the control module controls the first switching circuit to close and the second switching circuit, the lower arm of each pair of switch arms, and the first switch tube to disconnect, forming a circuit including the energy storage module, the first switching circuit, the power supply module, and the diodes in the lower arm of each pair of switch arms, and the energy storage module is used to charge the power supply module.

[0381] To facilitate understanding of the control flow for heating a battery pack according to an embodiment of the present application, a brief description will be given below of an embodiment in which a motor is used to heat the battery, with reference to FIG. 36. As shown in FIG. 36, the battery heating control process includes the following steps:

[0382] S601, the BMS collects battery parameters including the temperature, SOC, voltage signal and current signal of the battery pack.

[0383] In step S602, the BMS determines whether the heating conditions are met based on the battery parameters. If the heating conditions are met, the BMS sends a corresponding heating request to the VCU based on the SOC state, for example, sending the power required to heat the VCU to a preset temperature.

[0384] S603, the BMS or VCU determines whether the battery SOC is greater than a first threshold.

[0385] S604, if the SOC is greater than the first threshold, heat generated by the AC current flowing through the motor circuit is used to heat the power battery.

[0386] S605, when the SOC is equal to or less than the first threshold, heat generated by the DC current flowing through the motor circuit is used to heat the power battery.

[0387] After S604, the VCU reads the current operating state of the first motor.

[0388] For example, when the first motor is in a driving state (i.e., in an operating state), the VCU sends a driving signal to the motor controller, and the motor controller sends an enable signal to the switch module and the charge / discharge switching module to turn on the upper arm or the lower arm of the M-phase arm of the switch module and the first switching circuit or the second switching circuit of the charge / discharge switching module.

[0389] In one example, the motor controller periodically sends an enable signal to control the arming of the switch module and the on or off of the charge / discharge switching module, thereby realizing the switching between the charge circuit and the discharge circuit and the inverter control of the power battery current.

[0390] In S606, the BMS determines whether or not there is an abnormality in the temperature of the battery pack. If there is, it sends information indicating that the temperature rise is abnormal to the VCU. The VCU then transfers the information indicating that the temperature rise is abnormal to the motor controller and stops heating.

[0391] If it is determined in S607 and S606 that there is no abnormality in the temperature rise, the BMS determines whether the temperature of the battery pack has reached the required level. If it has reached the required level, the VCU transfers heating stop information to the motor controller and stops heating; if not, it repeats steps S601 to S606.

[0392] The embodiments of the present application may be used in a scenario where a relatively low-temperature power battery is heated. For example, the embodiment may be used in a specific scenario where the temperature of the power battery is increased by heating the power battery so that the battery pack can reach a temperature at which it can be normally used. Specifically, in the embodiments of the present application, when the battery State of Charge (SOC) is greater than a first threshold, the current flowing through the circuit is modulated to an AC current, and the AC current is used to generate heat through the internal resistance of the power battery, thereby heating the power battery and improving heating efficiency. When the battery SOC is less than the first threshold, i.e., when the battery power is insufficient, the DC current is used to generate heat in the windings to heat the power battery, thereby reducing power consumption and improving the flexibility of the power battery heating system.

[0393] 37 shows a schematic block diagram of a control circuit 700 of a charging / discharging system according to an embodiment of the present application. As shown in FIG. 37, the control circuit 700 includes a processor 710, and optionally, the control circuit 700 further includes a memory 720, where the memory 720 is used to store instructions, and the processor 710 is used to read the instructions and execute the control methods of the various embodiments of the present application described above based on the instructions.

[0394] An embodiment of the present application further provides a readable storage medium, used to store a computer program for performing the methods of the various embodiments of the present application described above.

[0395] As can be appreciated by those skilled in the art, the units and algorithm steps of each example described in connection with the embodiments disclosed herein can be realized in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can implement the described functions using different methods for each specific application, but such implementation should not be considered to go beyond the scope of this application.

[0396] As will be apparent to those skilled in the art, for the sake of convenience and conciseness of description, the specific operating processes of the above-described systems, devices and units may refer to the corresponding processes in the above-described method embodiments, and will not be further described here.

[0397] It should be understood that in some embodiments of the present application, the disclosed systems, devices, and methods may be realized in other ways. For example, the device embodiments described above are merely exemplary, and the division of the units is merely a logical functional division. In actual implementation, other division methods may be used. For example, multiple units or assemblies may be combined or integrated into another system, or some features may be omitted or not implemented. Furthermore, the couplings or direct couplings or communication connections between the devices shown or discussed may be indirect couplings or communication connections through some interfaces, devices, or units, and may be electrical, mechanical, or other types of couplings.

[0398] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, located in one location, or distributed across multiple network units, some or all of which may be selected to achieve the objectives of the solution of this embodiment according to actual needs.

[0399] Furthermore, each functional unit in each embodiment of the present application may be integrated into a single processing unit, each unit may exist physically alone, or two or more units may be integrated into a single unit.

[0400] When the functions are realized in the form of software functional units and sold or used as independent products, they may be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the present application, in substance or in the form of software products, may be embodied in the form of software products, including the parts that contribute to the prior art or the parts of the technical solutions. A computer software product is stored in a storage medium and includes some instructions for causing a computer device (such as a personal computer, a server, or a network device) to execute all or some of the steps of the methods of each embodiment of the present application. The aforementioned storage medium includes various media capable of storing program code, such as a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0401] As mentioned above, the above are merely specific embodiments of the present application, and the scope of protection of the present application is not limited thereto. Any modifications or replacements that can be easily conceived by anyone skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be equivalent to the scope of protection of the claims.

Claims

1. A charge / discharge circuit, The device includes a power supply module, a heating module, and a charge / discharge switching module, the power supply module includes at least a first assembled battery; the heating module includes an energy storage module and a switch module; the at least first assembled battery, the switch module, and the charge / discharge switching module are connected in parallel; a first end of the energy storage module is connected to the switch module, and a second end of the energy storage module is connected to the charge / discharge switching module; the charge / discharge switching module and the switch module are used to generate an AC waveform current in the charge / discharge circuit in response to a charge / discharge enable signal; the power supply module includes the first assembled battery, The charging / discharging circuit, wherein the charging / discharging switching module and the switch module are used to respond to a charging / discharging enable signal, and the waveform of the AC current generated in the charging / discharging circuit includes any one of a triangular waveform, a quasi-triangular waveform, a sine waveform, and a quasi-sine waveform.

2. The charge / discharge switching module includes a first switching circuit and a second switching circuit connected in series; a connection point between the first switching circuit and the second switching circuit is connected to a second end of the energy storage module; The charge / discharge circuit according to claim 1 , wherein the first switching circuit and the second switching circuit are used to be turned on or off by being triggered by the charge / discharge enable signal.

3. the first switching circuit includes a first upper arm, and the second switching circuit includes a first lower arm; a connection point between the first upper arm and the first lower arm is connected to a second end of the energy storage module; The charge / discharge circuit according to claim 2 , wherein the first upper arm and the first lower arm are used to be turned on or off by a trigger of the charge / discharge enable signal.

4. the first upper arm includes a first switch and a first diode connected in parallel, and the first lower arm includes a second switch and a second diode connected in parallel, 4. The charge / discharge circuit according to claim 3, wherein a cathode of the first diode is connected to a positive electrode of the first assembled battery, an anode of the first diode is connected to a cathode of the second diode, and an anode of the second diode is connected to a negative electrode of the first assembled battery.

5. The charge / discharge circuit according to claim 3 , wherein the first upper arm includes a third switch and the first lower arm includes a fourth switch.

6. the first switching circuit includes a third diode, and the second switching circuit includes a fifth switch; 3. The charge / discharge circuit according to claim 2, wherein a cathode of the third diode is connected to a positive electrode of the first assembled battery, an anode of the third diode is connected to one end of the fifth switch, and the other end of the fifth switch is connected to a negative electrode of the first assembled battery.

7. 7. The charge / discharge circuit according to claim 6, wherein the first switching circuit further includes a sixth switch, one end of the sixth switch being connected to a positive electrode of the first assembled battery and the other end of the sixth switch being connected to a cathode of the third diode.

8. the first switching circuit includes a seventh switch, and the second switching circuit includes a fourth diode; 3. The charge / discharge circuit according to claim 2, wherein one end of the seventh switch is connected to a positive electrode of the first assembled battery, the other end of the seventh switch is connected to a cathode of the fourth diode, and the anode of the fourth diode is connected to a negative electrode of the first assembled battery.

9. the second switching circuit further includes an eighth switch; 9. The charge / discharge circuit according to claim 8, wherein the eighth switch is connected in series between the fourth diode and the negative electrode of the first assembled battery.

10. 2. The charging / discharging circuit of claim 1, wherein the energy storage module includes a first energy storage element, the first energy storage element including at least one inductor, a first end of the first energy storage element connected to the switch module, and a second end of the first energy storage element connected to the charging / discharging switching module.

11. 11. The charging / discharging circuit of claim 10, wherein the energy storage module further includes a second energy storage element, the second energy storage element being connected between a second end of the first energy storage element and the charging / discharging switching module.

12. 12. The charging / discharging circuit according to claim 11, wherein a ninth switch is connected between the energy storage module and the charge / discharge switching module, and the ninth switch is connected in series with the second energy storage element.

13. The switch module includes at least one pair of switch arms, and the first energy storage element in the energy storage module includes at least one energy storage device, the number of the energy storage devices is equal to the number of the switch arms, and the energy storage devices are connected to the switch arms in a one-to-one correspondence; The charging / discharging circuit according to claim 1 , wherein a connection point of the second end of each of the energy storage devices is connected to the charging / discharging switching module.

14. 14. The charging / discharging circuit of claim 13, wherein each set of switch arms includes an upper arm and a lower arm, and each of the upper arm and the lower arm includes a switch and a diode connected in parallel, or each of the upper arm and the lower arm includes a switch.

15. 2. The charging / discharging circuit of claim 1, wherein the switch module includes at least one pair of switch legs, the at least one pair of switch legs including a switch and a diode connected in series, the first energy storage element in the energy storage module includes at least one energy storage device, the number of the energy storage devices is equal to the number of the switch legs, and the energy storage devices are connected in one-to-one correspondence with the switch legs.

16. the energy storage module includes an M-phase motor, the switch module includes M-phase arms, M is a positive integer, Here, the M-phase arm, the power supply module, and the charge / discharge switching module are connected in parallel, connection points of the upper and lower arms of the M-phase arm are connected to M-phase windings of the M-phase motor in one-to-one correspondence, respectively; The charge / discharge circuit according to claim 1 , wherein the charge / discharge switching module is connected to a connection point of the M-phase winding.

17. the M-phase motor includes a first M-phase motor and a second M-phase motor; 17. The charge / discharge circuit according to claim 16, wherein a connection point of an M-phase winding of the first M-phase motor is connected to a connection point of an M-phase winding of the second M-phase motor.

18. the power supply module includes at least a first assembled battery and a second assembled battery; the charge / discharge switching module and the switch module are used to generate an AC current with a square wave or a quasi-square wave in the charge / discharge circuit in response to a first charge / discharge enable signal, or are used to generate an AC current with any one of a triangular waveform, a quasi-triangular wave, a sine waveform, and a quasi-sine waveform in the charge / discharge circuit in response to a second charge / discharge enable signal; 2. The charge / discharge circuit according to claim 1, wherein a charge / discharge frequency corresponding to the first charge / discharge enable signal is higher than a charge / discharge frequency corresponding to the second charge / discharge enable signal.

19. a first end of the second assembled battery is connected to a first end of the charge / discharge switching module, and a second end of the second assembled battery, a second end of the first assembled battery, a second end of the switch module, and a second end of the charge / discharge switching module are connected to the same line; a first end of the first assembled battery is connected to a first end of the switch module; 19. The charge / discharge circuit according to claim 18, further comprising a tenth switch connected between the first end of the first assembled battery and the first end of the second assembled battery.

20. 19. The charging / discharging circuit of claim 18, wherein a first end of the energy storage module is connected to a first end of the switch module and a second end of the energy storage module is connected to a first end of the charge / discharge switching module, or a first end of the energy storage module is connected to a second end of the switch module and a second end of the energy storage module is connected to a second end of the charge / discharge switching module.

21. 10. A charging / discharging system comprising: a control module; and the charging / discharging circuit according to claim 1, wherein the control module is used to control a power supply module to perform charging / discharging by sending a command to the charging / discharging circuit.

22. A charge / discharge control method, 22. The charge / discharge control method for use in the charge / discharge system according to claim 21, a charge / discharge control method including: sending a charge / discharge enable signal to control the charge / discharge switching module and the switch module to be on or off, and causing the charge / discharge circuit to form a charge circuit and a discharge circuit that alternately switch, thereby generating an AC waveform current.

23. 23. The charge / discharge control method according to claim 22, wherein the charge / discharge switching module and the switch module are alternately sent a charge enable signal and a discharge enable signal at a preset frequency, thereby controlling the charge circuit and the discharge circuit to be alternately switched.

24. The charge / discharge switching module includes a first switching circuit and a second switching circuit connected in series, and the switch module includes at least one pair of switch arms, each pair of switch arms including an upper arm and a lower arm; The alternating charging and discharging circuits include: a circuit between the upper arm of each pair of the switch modules, the energy storage module, the second switching circuit, and the power supply module; The charge / discharge control method according to claim 22, including a circuit between the lower arm of each set of the switch module, the energy storage module, the first switching circuit, and the power supply module.

25. the power supply module includes at least a first assembled battery; the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, the second switching circuit includes a first lower arm; the switch module includes at least one pair of switch arms; Send a discharge enable signal to turn on the first upper arm and the lower arm of each set of the switch arms, thereby forming a discharge circuit between the power supply module, the first upper arm, the energy storage module, and the lower arm of each set of the switch arms; Send a charging enable signal to turn on the first lower arm and the upper arm of each set of the switch arms, thereby forming a charging circuit between the power supply module, the first lower arm, the energy storage module, and the upper arm of each set of the switch arms; and / or Send a discharge enable signal to turn on the upper arm and the first lower arm of each set of the switch arms, thereby forming a discharge circuit between the power supply module and the upper arm of each set of the switch arms, and between the energy storage module and the first lower arm; 23. The charge / discharge control method according to claim 22, further comprising: transmitting a charge enable signal to control the lower arm of the switch arm and the first upper arm of each set to be on, and forming a charging circuit between the power supply module and the lower arm of each set of the switch arm, and between the energy storage module and the first upper arm.

26. the power supply module includes at least a first assembled battery; the charge / discharge switching module includes a first switching circuit and a second switching circuit; the first switching circuit includes a third diode; the second switching circuit includes a fifth switch; and the switch module includes at least one pair of switch arms; Send a discharge enable signal to turn on the upper arm of each set of switch arms and the fifth switch, thereby forming a discharge circuit between the power supply module, the upper arm of each set of switch arms, the energy storage module, and the fifth switch; 23. The charge / discharge control method according to claim 22, further comprising: transmitting a charge enable signal to control the lower arm of each set of switch arms to be on, and forming a charging circuit between the power supply module, the lower arm of each set of switch arms, the energy storage module, and the third diode.

27. the power supply module includes at least a first assembled battery; the charge / discharge switching module includes a first switching circuit and a second switching circuit; the first switching circuit includes a seventh switch; the second switching circuit includes a fourth diode, an anode of the fourth diode is connected to a negative electrode of the first assembled battery; and the switch module includes at least one pair of switch arms; Send a discharge enable signal to turn on the seventh switch and the lower arm of each set of the switch arms, thereby forming a discharge circuit between the power supply module, the seventh switch, the energy storage module, and the lower arm of each set of the switch arms; Send a charging enable signal to turn on the upper arm of each set of the switch arms, and form a charging circuit between the power supply module, the fourth diode, the energy storage module, and the upper arm of each set of the switch arms; or a cathode of the fourth diode is connected to a negative electrode of the first assembled battery; Send a discharge enable signal to turn on the upper arm of each set of the switch arms, thereby forming a discharge circuit between the power supply module, the upper arm of each set of the switch arms, the energy storage module, and the fourth diode; 23. The charge / discharge control method according to claim 22, further comprising: sending a charge enable signal to turn on the seventh switch and the lower arm of each set of the switch arms, thereby forming a charging circuit between the power supply module, the lower arm of each set of the switch arms, the energy storage module, and the seventh switch.

28. the power supply module includes at least a first assembled battery, the energy storage module includes a first M-phase motor and a second M-phase motor, the switch module includes an M-phase arm, the charge / discharge switching module includes an M-phase arm, M-phase windings of the first M-phase motor are connected to the M-phase arms of the switch module in a one-to-one correspondence, M-phase windings of the second M-phase motor are connected to the M-phase arms of the charge / discharge switching module in a one-to-one correspondence, and a connection point of the M-phase winding of the first M-phase motor is connected to a connection point of the M-phase winding of the second M-phase motor, a discharge enable signal is sent to control the upper arm of the M-phase arm of the switch module and the lower arm of the M-phase arm of the charge / discharge switching module to be turned on, thereby forming a discharge circuit between the power supply module, the upper arm of the M-phase arm of the switch module, the first M-phase motor, the second M-phase motor, and the lower arm of the M-phase arm of the charge / discharge switching module; Sending a charge enable signal to turn on the upper arm of the M-phase arm of the charge / discharge switching module and the lower arm of the M-phase arm of the switch module, thereby forming a charging circuit between the power supply module, the lower arm of the M-phase arm of the switch module, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the charge / discharge switching module; and / or sending a discharge enable signal to control the upper arm of the M-phase arm of the charge / discharge switching module and the lower arm of the M-phase arm of the switch module to be on, thereby forming a discharge circuit between the power supply module, the lower arm of the M-phase arm of the switch module, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the charge / discharge switching module; 23. The charge / discharge control method according to claim 22, further comprising transmitting a charge enable signal to control an upper arm of the M-phase arm of the switch module and a lower arm of the M-phase arm of the charge / discharge switching module to be turned on, thereby forming a charging circuit between the power supply module, the lower arm of the M-phase arm of the charge / discharge switching module, the first M-phase motor, the second M-phase motor, and the upper arm of the M-phase arm of the switch module.

29. the power supply module includes at least a first assembled battery and a second assembled battery; charging and discharging the first assembled battery or the second assembled battery via the charging circuit or the discharging circuit, and generating a square wave or pseudo-square wave AC current in the charging and discharging circuit; 23. The charge / discharge control method according to claim 22, wherein the charging / discharging includes switching between charge / discharge states of the first assembled battery and the second assembled battery, and the charge / discharge states include charging the first assembled battery and discharging the second assembled battery, or discharging the first assembled battery and charging the second assembled battery.

30. a first end of the second assembled battery is connected to a first end of the charge / discharge switching module; a second end of the second assembled battery, a second end of the first assembled battery, a second end of the switch module, and a second end of the charge / discharge switching module are connected to the same line; a first end of the first assembled battery is connected to the first end of the switch module; and a tenth switch is connected between the first end of the first assembled battery and the first end of the second assembled battery; and the charge / discharge control method comprises:

30. The charge / discharge control method according to claim 29, further comprising determining that the first assembled battery and the second assembled battery satisfy a heating condition, and controlling the tenth switch to be turned off.

31. the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, and the second switching circuit includes a first lower arm; the switch module includes at least one pair of switch arms; one end of the energy storage module is connected to a connection point between the first upper arm and the first lower arm, and the other end of the energy storage module is connected to a connection point between the upper and lower arms of the switch arms; sending a first enable signal to turn on the first upper arm and the lower arm of each set of the switch arms, thereby forming a discharge circuit between the first assembled battery, the first upper arm, the energy storage module, and the lower arm of each set of the switch arms, and discharging the first assembled battery to the energy storage module; 31. The charge / discharge control method according to claim 30, further comprising transmitting a second enable signal to control the first upper arm and the upper arms of each set of the switch arms to be on, forming a charging circuit between the first assembled battery, the first upper arm, the energy storage module, the upper arms of each set of the switch arms, and the second assembled battery, and causing the first assembled battery and the energy storage module to charge the second assembled battery.

32. 32. The charge / discharge control method according to claim 31, further comprising controlling a charging time for the second assembled battery by repeatedly switching on an upper arm or a lower arm of each set of the switch arms.

33. sending a third enable signal to control the first lower arm and the upper arm of each set of the switch arms to be on, thereby forming a discharge circuit between the second assembled battery, the upper arm of each set of the switch arms, the energy storage module, and the first lower arm, and discharging the second assembled battery to the energy storage module; 32. The charge / discharge control method according to claim 31, further comprising: transmitting a fourth enable signal to control the first upper arm and the upper arms of each set of the switch arms to be on, forming a charging circuit between the second assembled battery, the upper arms of each set of the switch arms, the energy storage module, the first upper arm, and the first assembled battery, and charging the second assembled battery and the energy storage module to the first assembled battery.

34. 34. The charge / discharge control method according to claim 33, further comprising controlling a charging time for the first assembled battery by repeatedly switching on the first upper arm or the first lower arm.

35. the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, the second switching circuit includes a first lower arm, the switch module includes at least one pair of switch arms, a first end of the energy storage module is connected to a first end of the switch module, and a second end of the energy storage module is connected to a first end of the charge / discharge switching module; Send a first enable signal to simultaneously turn on the first lower arm and the upper arm of each set of the switch arms, thereby forming a circuit for discharging the first assembled battery to the energy storage module; Send a second enable signal to simultaneously turn on the lower arm and the first lower arm of each pair of switch arms, so that the first assembled battery and the energy storage module form a circuit for charging the second assembled battery; and / or Sending a third enable signal to simultaneously turn on the first upper arm and the lower arm of each set of the switch arms, thereby forming a circuit for discharging the second assembled battery to the energy storage module; 31. The charge / discharge control method according to claim 30, further comprising transmitting a fourth enable signal to simultaneously control the first lower arm and the lower arms of each set of the switch arms to be on, so that the second assembled battery and the energy storage module form a circuit that charges the first assembled battery.

36. the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, the second switching circuit includes a first lower arm, the switch module includes at least one pair of switch arms, a first end of the energy storage module is connected to a second end of the switch module, and the second end of the energy storage module is connected to a second end of the charge / discharge switching module; Send a first enable signal to simultaneously turn on the first lower arm and the upper arm of each set of the switch arms, thereby forming a circuit for discharging the second assembled battery to the energy storage module; Send a second enable signal to simultaneously turn on the upper arm and the first upper arm of each pair of switch arms, so that the second assembled battery and the energy storage module form a circuit for charging the first assembled battery; and / or Sending a third enable signal to simultaneously turn on the first upper arm and the lower arm of each set of the switch arms, thereby forming a circuit for discharging the first assembled battery to the energy storage module; 31. The charge / discharge control method according to claim 30, further comprising transmitting a fourth enable signal to simultaneously control the first upper arm and the upper arms of each set of the switch arms to be turned on, so that the first assembled battery and the energy storage module form a circuit for charging the second assembled battery.

37. the charge / discharge switching module includes a first switching circuit and a second switching circuit, the first switching circuit includes a first upper arm, and the second switching circuit includes a first lower arm; the switch module includes at least one pair of switch arms; one end of the energy storage module is connected to a connection point between the first upper arm and the first lower arm, and the other end of the energy storage module is connected to a connection point between the upper and lower arms of the switch arms; 31. The charge / discharge control method according to claim 30, further comprising: transmitting a first enable signal to control the first upper arm and the upper arms of each set of the switch arms to be on, forming a charge / discharge circuit between the first assembled battery, the upper arms of each set of the switch arms, the energy storage module, the first upper arm, and the second assembled battery, discharging the first assembled battery to the energy storage module, and charging the first assembled battery and the energy storage module to the second assembled battery; transmitting a second enable signal to control the first upper arm and the upper arms of each set of the switch arms to be on, forming a charge / discharge circuit between the first assembled battery, the first upper arm, the energy storage module, the upper arms of each set of the switch arms, and the second assembled battery, discharging the second assembled battery to the energy storage module, and charging the second assembled battery from the second assembled battery and the energy storage module.

38. a ninth switch is connected between the energy storage module and the charge / discharge switching module; Determine that the battery pack included in the power supply module satisfies a heating condition and control the ninth switch to close; or The charge / discharge control method according to claim 22, further comprising determining that the battery pack satisfies a heating stop condition and controlling the ninth switch to be turned off.

39. Before transmitting the charge / discharge enable signal, the charge / discharge control method includes: determining whether the temperature of the power supply module is less than a preset temperature threshold; If so, determining whether the state-of-charge value of each battery pack in the power supply module is equal to or greater than a predetermined charge threshold; 23. The charge / discharge control method according to claim 22, further comprising: when the state-of-charge value of each assembled battery is equal to or greater than the predetermined threshold, alternately transmitting a charge / discharge enable signal to the charge / discharge switching module and the switch module at a predetermined frequency.

40. Before transmitting the charge / discharge enable signal, the charge / discharge control method includes: Obtaining the operating status of the motor; 23. The charge / discharge control method of claim 22, further comprising: when the operating state indicates that the motor is in a non-driving state, alternately sending a charge / discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency.

41. Before transmitting the charge / discharge enable signal, the charge / discharge control method includes: receiving a control signal transmitted from a vehicle controller; 23. The charge / discharge control method of claim 22, further comprising: when the control signal instructs the power supply module to heat, alternately sending a charge / discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency.

42. Before transmitting the charge / discharge enable signal, the charge / discharge control method includes: receiving request data transmitted from the battery management system; 23. The charge / discharge control method of claim 22, further comprising: when the request data indicates that the power supply module satisfies a heating condition, alternately sending a charge / discharge enable signal to the charge / discharge switching module and the switch module at a preset frequency.

43. The charging / discharging system further includes a charging device, and the charging / discharging control method includes: If the voltage of the charging device is lower than the voltage of the power supply module, the switch module and the charge / discharge switching module, and the charging device controls the energy storage module. a circuit for charging the module, and the charging device and the energy storage module are connected to the power supply module; forming a circuit for simultaneously charging the joules; When the voltage of the charging device is higher than the voltage of the power supply module, the switch module and the charging / discharging switching module, and the charging device controls the power supply module and the a circuit for charging the energy storage module, and The charge / discharge control method according to any one of claims 22 to 37, further comprising forming a circuit for charging the power supply module.

44. The end of the energy storage module connected to the switch module is connected to one end of a charging device through a first switch tube, and the second end of the switch module is connected to the other end of the charging device, and the charging device is used to charge the power supply module through the heating module, the switch module includes at least one pair of switch arms, and the charge / discharge switching module includes a first switching circuit and a second switching circuit, and the charge / discharge control method includes: Controlling the upper arm of each set of switch arms to be cut off; When the voltage of the charging device is lower than the voltage of the power supply module, control the second switching circuit and the first switch tube to be on, and the first switching circuit and the lower arm of each pair of switch arms to be off, so as to form a circuit including the charging device, the energy storage module and the second switching circuit, for the charging device to charge the energy storage module; Controlling the first switching circuit and the first switch tube to be on, and the second switching circuit and the lower arm of each pair of switch arms to be off, to form a circuit including the charging device, the energy storage module, the first switching circuit and the power supply module, so that the charging device and the energy storage module simultaneously charge the power supply module; and / or When the voltage of the charging device is higher than the voltage of the power supply module, control the first switching circuit and the first switch tube to close, and the second switching circuit and the lower arm of each pair of switch arms to disconnect, so as to form a circuit including the charging device, the energy storage module, the first switching circuit and the power supply module, for the charging device to charge the power supply module and the energy storage module; 44. The charge / discharge control method according to claim 43, further comprising: controlling to close the first switching circuit and disconnect the second switching circuit, the lower arm of each set of switch arms, and the first switch tube; and forming a circuit including the energy storage module, the first switching circuit, the power supply module, and diodes in the lower arm of each set of switch arms, for the energy storage module to charge the power supply module.

45. 22. An electric power consuming device comprising the charging / discharging system according to claim 21.

Images