Heating control system for battery, and vehicle

Abstract

A heating control system for a battery. The heating control system comprises a first bridge arm converter (11), a second bridge arm converter (12), a third bridge arm converter (13) and a controller (20), wherein the first bridge arm converter is connected to positive and negative electrodes of a traction battery (40) and a winding of a first electric motor (31), respectively, the second bridge arm converter is connected to the positive and negative electrodes of the traction battery and a winding of a second electric motor (32), respectively, and the third bridge arm converter is connected to the positive and negative electrodes of the traction battery and a winding of a third electric motor (33), respectively; and the controller is connected to the first bridge arm converter, the second bridge arm converter and the third bridge arm converter, respectively, and is used for controlling at least one of the bridge arm converters to operate, such that the traction battery performs charging and / or discharging on a winding in at least one of the electric motors, so as to heat the traction battery. Further provided is a vehicle. The heating control system for a battery can mitigate the degradation of the power output performance of a vehicle having a three-electric-motor drive system caused by a low temperature, thereby increasing the driving range.

Description

Heating control system of battery and vehicle

[0001] Cross-reference to related disclosures

[0002] The present disclosure claims priority to Chinese patent application No. 202410844170.1, filed on June 26, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure relates to the field of vehicles, and more particularly to a heating control system of battery and vehicle. BACKGROUND

[0004] In recent years, with the development of electric vehicle related technologies, distributed drive technology has gradually become the main direction of research on the driving mode of new energy vehicles. Distributed drive refers to the dispersion of driving force in the vehicle power system to multiple drive units, for example, a three-motor drive system drives the front wheels through a single motor and drives the left and right rear wheels through double motors, thereby achieving better handling performance and stability and enabling more intelligent driving modes. TECHNICAL PROBLEM

[0005] Low temperature environment can cause the battery to have a reduced equilibrium potential, increased internal resistance, and reduced discharge capacity. In extreme low temperature conditions, the electrolyte can freeze and the battery can not be discharged, which greatly affects the low temperature performance of the battery system and causes the three-motor drive system vehicle to have reduced power output performance and reduced range in winter. TECHNICAL SOLUTION

[0006] The present disclosure is proposed in consideration of the above problems. The present disclosure provides a heating control system of battery and vehicle, which can reduce the power output performance attenuation of the three-motor drive system vehicle caused by low temperature and improve the range.

[0007] According to a first aspect of the present disclosure, a heating control system of battery is provided, applied to a vehicle including a power battery, a first motor, a second motor, and a third motor, the heating control system comprising:

[0008] a first bridge arm converter, a second bridge arm converter, a third bridge arm converter, and a controller, the first bridge arm converter being connected with the positive and negative electrodes of the power battery and the winding of the first motor, the second bridge arm converter being connected with the positive and negative electrodes of the power battery and the winding of the second motor, and the third bridge arm converter being connected with the positive and negative electrodes of the power battery and the winding of the third motor;

[0009] The controller is connected with the first bridge arm converter, the second bridge arm converter and the third bridge arm converter respectively, and is configured to control at least one of the first bridge arm converter, the second bridge arm converter and the third bridge arm converter to work, so that the power battery charges and / or discharges at least one winding of the first motor, the second motor and the third motor, to realize heating of the power battery.

[0010] In one embodiment of the present disclosure, the heating control system further comprises a first switch and a second switch, the power battery comprises a first battery module and a second battery module connected in series, the neutral point of the first motor is connected with the neutral point of the second motor through the first switch, and the neutral point of the third motor is connected with the connection point of the first battery module and the second battery module through the second switch.

[0011] In one embodiment of the present disclosure, the controller is connected with the control ports of the first switch and the second switch respectively, and is configured to control the first switch to be turned off and the second switch to be turned on, so that the power battery enters a module heating mode, or control the first switch to be turned on and the second switch to be turned off, so that the power battery enters a whole-pack heating mode.

[0012] In one embodiment of the present disclosure, when the power battery enters the module heating mode, the controller is further configured to control the upper bridge switch and the lower bridge switch of the third bridge arm converter to be turned on alternately according to a preset first time sequence, to form an electricity storage loop comprising the first battery module or the second battery module, so that the winding of the third motor stores electricity, and to form a discharging loop comprising the second battery module or the first battery module, so that the winding of the third motor discharges to the second battery module or the first battery module.

[0013] In one embodiment of the present disclosure, when the power battery enters the whole-pack heating mode, the controller is further configured to control the upper bridge switch and the lower bridge switch of the first bridge arm converter and the second bridge arm converter to be turned on alternately according to a preset second time sequence, to form an electricity storage loop comprising the power battery, so that the windings of the first motor and the second motor store electricity, and to form a discharging loop comprising the power battery, so that the windings of the first motor and the second motor discharge to the power battery.

[0014] In one embodiment of the present disclosure, the heating control system further comprises a direct-current charging interface, the first end of each phase bridge arm of the first bridge arm converter is connected with the positive electrode of the direct-current charging interface, and the negative electrode of the direct-current charging interface is connected with the second end of each phase bridge arm of the first bridge arm converter.

[0015] In one embodiment of the present disclosure, the controller is further configured to control the first switch to be turned on and the second switch to be turned off, and control the upper bridge switch and the lower bridge switch of the first bridge arm converter and the second bridge arm converter to be turned on alternately according to a preset third timing, so as to form an electricity storage loop including the power battery, so that the windings of the first motor and the second motor are stored with electricity, and form a discharging loop including the DC charging interface, so that the windings of the first motor and the second motor discharge electricity to the DC charging interface.

[0016] In one embodiment of the present disclosure, the first end of each phase bridge arm of the first bridge arm converter is adapted to be connected with the positive pole of the charging pile interface, and the second end of each phase bridge arm of the first bridge arm converter is adapted to be connected with the negative pole of the charging pile interface.

[0017] In one embodiment of the present disclosure, the controller is further configured to control the first switch to be turned on and the second switch to be turned off, and control the upper bridge switch and the lower bridge switch of the first bridge arm converter and the second bridge arm converter to be turned on alternately according to a preset fourth timing, so as to form a charging loop including the charging pile interface, so that the windings of the first motor and the second motor are stored with electricity, and form a discharging loop including the power battery, so that the windings of the first motor and the second motor discharge electricity to the power battery.

[0018] In one embodiment of the present disclosure, the first bridge arm converter, the second bridge arm converter and the third bridge arm converter each include N phase bridge arms arranged in parallel, each phase bridge arm includes an upper bridge switch and a lower bridge switch, the first end of each phase bridge arm is connected with the positive pole of the power battery, and the second end of each phase bridge arm is connected with the negative pole of the power battery; wherein N is a positive integer greater than or equal to 1.

[0019] In one embodiment of the present disclosure, the first bridge arm converter, the second bridge arm converter and the third bridge arm converter each include three phase bridge arms arranged in parallel.

[0020] In one embodiment of the present disclosure, the upper bridge switch and the lower bridge switch each include an insulated gate bipolar transistor and a parallel-connected reverse diode.

[0021] In one embodiment of the present disclosure, the first motor, the second motor and the third motor each include N phase winding coils, the midpoint of each phase bridge arm is connected with the first end of one phase winding coil, and the second ends of the N phase winding coils are connected with each other to form the neutral point of each motor.

[0022] In one embodiment of the present disclosure, the first motor, the second motor and the third motor each include three phase winding coils.

[0023] According to a second aspect of the present disclosure, a vehicle is provided, comprising a power battery, a first motor, a second motor, a third motor, and the heating control system of the battery.

[0024] In an embodiment of the present disclosure, the power battery comprises a first battery module and a second battery module connected in series. Advantages

[0025] The heating control system of the battery of the present disclosure controls at least one of the first bridge arm converter, the second bridge arm converter, and the third bridge arm converter to work, so that the power battery charges and / or discharges at least one winding of the first motor, the second motor, and the third motor, to realize the heating of the power battery, thereby reducing the power output performance attenuation of the three-motor drive system vehicle caused by low temperature, and improving the cruising range of the vehicle. BRIEF DESCRIPTION OF DRAWINGS

[0026] The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. The drawings provided in the present disclosure are used to provide further understanding of the embodiments of the present disclosure, and constitute a part of the specification, which explain the present disclosure together with the embodiments of the present disclosure, but do not constitute a limitation to the present disclosure. In the drawings, the same reference numerals generally indicate the same components or steps throughout the drawings.

[0027] FIG. 1 is a schematic structural diagram of a heating control system of a battery according to an embodiment of the present disclosure;

[0028] FIG. 2 is a circuit structural diagram of a heating control system of a battery according to an embodiment of the present disclosure;

[0029] FIG. 3 is a schematic diagram of current flow in a module heating mode according to an embodiment of the present disclosure;

[0030] FIG. 4a is a schematic diagram of current flow in timing 1 in a whole package heating mode according to an embodiment of the present disclosure;

[0031] FIG. 4b is a schematic diagram of current flow in timing 2 in a whole package heating mode according to an embodiment of the present disclosure;

[0032] FIG. 5a is a schematic diagram of current flow in timing 1 in a boost-buck discharging mode according to an embodiment of the present disclosure;

[0033] FIG. 5b is a schematic diagram of current flow in timing 2 in a boost-buck discharging mode according to an embodiment of the present disclosure;

[0034] FIG. 6a is a schematic diagram of current flow in timing 1 in a boost-buck charging mode according to an embodiment of the present disclosure;

[0035] Fig. 6b is a schematic diagram of current flow direction of the boost charging timing 2 according to an embodiment of the present disclosure;

[0036] Fig. 7 is a schematic structural diagram of a vehicle according to an embodiment of the present disclosure.

[0037] Embodiments of the present disclosure

[0038] In order to make the purposes, technical solutions and advantages of the present disclosure more obvious, the example embodiments according to the present disclosure will be described in detail below with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure, and it should be understood that the present disclosure is not limited to the example embodiments described herein. Based on the embodiments of the present disclosure described in the present disclosure, all other embodiments obtained by those skilled in the art without creative labor should fall within the protection scope of the present disclosure.

[0039] In order to solve the problems of power output performance attenuation and reduced range of the vehicle with the existing three-motor drive system when driving in winter, the present disclosure proposes a battery heating control system and a vehicle, which can reduce the power output performance attenuation of the vehicle with the three-motor drive system caused by low temperature and improve the range, which will be described in detail below.

[0040] First, the battery heating control system according to the embodiment of the present disclosure is described with reference to Fig. 1.

[0041] As shown in Fig. 1, the battery heating control system provided by the present disclosure is applied to a vehicle including a power battery 40, a first motor 31, a second motor 32 and a third motor 33, and the heating control system includes:

[0042] A first bridge arm converter 11, a second bridge arm converter 12, a third bridge arm converter 13 and a controller 20. The first bridge arm converter 11 is connected with the positive and negative electrodes of the power battery 40 and the winding of the first motor 31 respectively, the second bridge arm converter 12 is connected with the positive and negative electrodes of the power battery 40 and the winding of the second motor 32 respectively, and the third bridge arm converter 13 is connected with the positive and negative electrodes of the power battery 40 and the winding of the third motor 33 respectively.

[0043] The controller 20 is connected with the first bridge arm converter 11, the second bridge arm converter 12 and the third bridge arm converter 13, and is used for controlling at least one of the first bridge arm converter 11, the second bridge arm converter 12 and the third bridge arm converter 13 to work, so that the power battery 40 charges and / or discharges at least one winding of the first motor 31, the second motor 32 and the third motor 33, to realize the heating of the power battery 40.

[0044] In Fig. 1, the solid line is the current transmission line, which is the connection line for realizing current transmission. The dashed line is the signal line for transmitting the control signal.

[0045] Here, the heating control system of the battery is a control device provided on the vehicle. The vehicle is provided with a power battery 40, three motors, three motor controllers and a vehicle-mounted controller. The vehicle-mounted controller refers to a controller provided on the vehicle. The three motor controllers are a first motor controller, a second motor controller and a third motor controller, the first motor controller is connected with the first motor and used for controlling the first motor to work, the second motor controller is connected with the second motor and used for controlling the second motor to work, and the third motor controller is connected with the third motor and used for controlling the third motor to work.

[0046] Among them, the first bridge arm converter 11 can be a bridge arm converter provided on the first motor controller, the second bridge arm converter 12 can be a bridge arm converter provided on the second motor controller, and the third bridge arm converter 13 can be a bridge arm converter provided on the third motor controller. The winding of the first motor 31 is the coil winding on the first motor, the winding of the second motor 32 is the coil winding on the second motor, and the winding of the third motor 33 is the coil winding on the third motor.

[0047] The first bridge arm converter 11 is connected with the power battery 40 and the winding of the first motor 31, and can control the conduction or disconnection between the power battery 40 and the winding of the first motor 31. The second bridge arm converter 12 is connected with the power battery 40 and the winding of the second motor 32, and can control the conduction or disconnection between the power battery 40 and the winding of the second motor 32. The third bridge arm converter 13 is connected with the power battery 40 and the winding of the third motor 33, and can control the conduction or disconnection between the power battery 40 and the winding of the third motor 33.

[0048] The heating control system of the battery of the present disclosure controls at least one of the first bridge arm converter, the second bridge arm converter and the third bridge arm converter to work, so that the power battery charges and / or discharges at least one winding of the first motor, the second motor and the third motor, to realize the heating of the power battery, thereby reducing the power output performance attenuation of the three-motor drive system vehicle caused by low temperature, and improving the cruising range of the vehicle.

[0049] According to one embodiment of the present disclosure, the heating control system further comprises a first switch and a second switch, the power battery comprises a first battery module and a second battery module connected in series; the neutral point of the first motor is connected with the neutral point of the second motor through the first switch, and the neutral point of the third motor is connected with the connection point of the first battery module and the second battery module through the second switch.

[0050] Under the control of the first switch, the neutral points of the first motor and the second motor are connected, so that the windings of the first motor and the second motor can transmit current between each other, thereby providing technical support for simultaneously oscillating and heating the power battery through the two motors.

[0051] Under the control of the second switch, the neutral point of the third motor is connected with the negative electrode of the first battery module and the positive electrode of the second battery module, thereby providing technical support for oscillating and heating the first battery module and the second battery module through the third motor respectively.

[0052] According to one embodiment of the present disclosure, the first bridge arm converter, the second bridge arm converter, and the third bridge arm converter each include N-phase bridge arms arranged in parallel, each phase bridge arm includes an upper bridge switch tube and a lower bridge switch tube, a first end of each phase bridge arm is connected with the positive electrode of the power battery, and a second end of each phase bridge arm is connected with the negative electrode of the power battery; wherein N is a positive integer greater than or equal to 1.

[0053] In this embodiment, the switch tube includes an insulated gate bipolar transistor and a parallel-connected reverse diode, so that current transmission in two directions can be realized. The reverse diode is used to prevent reverse current transmission.

[0054] According to one embodiment of the present disclosure, the first motor, the second motor, and the third motor each include N-phase winding coils, a midpoint of each phase bridge arm is connected with a first end of one phase winding coil, and second ends of the N-phase winding coils are connected with each other to form a neutral point of each motor.

[0055] Figure 2 is a circuit structure diagram of a battery heating control system according to one embodiment of the present disclosure. As shown in Figure 2, in one embodiment, the first bridge arm converter 11, the second bridge arm converter 12, and the third bridge arm converter 13 each include three-phase bridge arms arranged in parallel, each phase bridge arm includes an upper bridge switch tube and a lower bridge switch tube, a first end of each phase bridge arm is commonly connected to form a positive electrode bus connected with the positive electrode of the power battery 40, and a second end of each phase bridge arm is commonly connected to form a negative electrode bus connected with the negative electrode of the power battery 40.

[0056] The upper bridge switch tube is a switch tube connected with the positive electrode of the power battery 40 on the bridge arm, and the lower bridge switch tube is a switch tube connected with the negative electrode of the power battery 40 on the bridge arm. The upper bridge switch tube and the lower bridge switch tube are the midpoints of the bridge arm.

[0057] The first motor 31, the second motor 32 and the third motor 33 each include three-phase winding coils, the middle points of each phase bridge arm are connected with the first ends of one phase winding coil respectively, and the second ends of the three-phase winding coils are connected with each other to form the neutral points of each motor, that is, one end of each of the three winding coils is led out through one lead wire, so that the three lead wires are connected together to form the neutral point. Therefore, in the process of discharging the winding of the motor by the power battery 40 and storing the discharged electric energy in the winding of the motor, the current needs to pass through the upper bridge switch tube or the lower bridge switch tube to form a loop with the winding coil.

[0058] The first switch K1 is arranged between the neutral point of the first motor 31 and the neutral point of the second motor 32, and the second switch K2 is arranged between the neutral point of the third motor 33 and the negative electrode of the first battery module and the positive electrode of the second battery module.

[0059] The controller (not shown in the figure) is connected with the control ports of the first switch K1 and the second switch K2 respectively, and is used to control the first switch K1 to be turned off and the second switch K2 to be turned on, so that the power battery enters the module heating mode; or control the first switch K1 to be turned on and the second switch K2 to be turned off, so that the power battery enters the whole package heating mode.

[0060] According to one embodiment of the present disclosure, when the power battery enters the module heating mode, the controller is further used to control the upper bridge switch tube and the lower bridge switch tube of the third bridge arm converter to be turned on alternately according to a preset first time sequence, form a power storage loop including the first battery module or the second battery module to make the winding of the third motor store power, and form a discharge loop including the second battery module or the first battery module to make the winding of the third motor discharge power to the second battery module or the first battery module.

[0061] The whole charging and discharging process includes:

[0062] When the upper bridge switch tube of the third bridge arm converter is turned on, a power storage loop including the first battery module is formed to make the winding of the third motor store power; then the lower bridge switch tube is turned on to form a discharge loop including the second battery module to make the winding of the third motor discharge power to the second battery module.

[0063] When the lower bridge switch tube of the third bridge arm converter is turned on, a power storage loop including the second battery module is formed to make the winding of the third motor store power; then the upper bridge switch tube is turned on to form a discharge loop including the first battery module to make the winding of the third motor discharge power to the first battery module.

[0064] Next, the current flow in the module heating mode according to one embodiment of the present disclosure is described with reference to FIG. 3.

[0065] In this embodiment, when the module heating is started, the third motor 33 is used for battery self-heating, the second switch K2, the third switch K3 and the fourth switch K4 are attracted, and the first switch K1 is disconnected. In the power battery 40, the upper part is the first battery module, and the lower part is the second battery module.

[0066] The whole battery pack charging and discharging process includes four stages, namely time sequence 1-time sequence 4, and figure 3 shows the current flow direction (black arrow) of time sequence 1 and the current flow direction (gray arrow) of time sequence 2. The following describes time sequence 1-time sequence 4.

[0067] Time sequence 1: the current of the first battery module flows to the third motor through the k3 contactor, at this time the upper bridge of the third bridge arm converter is turned on and the lower bridge is disconnected. The current flows through the upper bridge of the third motor, the motor center line, the second switch K2 and the first battery module to form a loop, and the inductance of the third motor stores energy.

[0068] Time sequence 2: control the upper bridge of the third motor to be disconnected and the lower bridge to be turned on. Because of the inductance current continuation characteristic, the inductance stored energy flows to the second battery module through the second switch K2, forms a loop with the electric control lower bridge, and the energy stored in the inductance of the third motor is released to the second battery module.

[0069] Time sequence 3: control the upper bridge of the third motor to be disconnected and the lower bridge to be turned on. The second battery module charges the motor inductance, the positive current of the second battery module flows through the second switch K2, the motor center line, and the electric control lower bridge to form a loop, and the current flows to the negative electrode of the second battery module. The second battery module charges the motor inductance.

[0070] Time sequence 4: control the lower bridge of the third motor to be disconnected and the upper bridge to be turned on. Because of the inductance current continuation characteristic, the inductance stored energy flows to the first battery module through the second switch K2, forms a loop with the electric control upper bridge, and the energy stored in the inductance of the third motor is released to the first battery module.

[0071] Through the control of time sequence 1 to time sequence 4, the oscillation current of the first battery module and the second battery module can be formed, and the oscillation current generates a certain heat through the internal resistance of the battery pack. The heat can be calculated by the following formula: Q=I 2 *R*t

[0072] Wherein, Q is the heat, I is the current, R is the internal resistance of the battery, and t is the time of the current flowing through the battery.

[0073] According to one embodiment of the present disclosure, when the power battery enters the whole-pack heating mode, the controller is further configured to control the upper bridge switch and the lower bridge switch of the first bridge arm converter and the second bridge arm converter to be alternately turned on according to a preset second timing, to form an electricity storage loop including the power battery, so that the windings of the first motor and the second motor are stored with electricity, and to form a discharging loop including the power battery, so that the windings of the first motor and the second motor discharge electricity to the power battery.

[0074] Specifically, the controller can control the upper bridge switch of the first bridge arm converter to be turned off and the lower bridge switch to be turned on, the upper bridge switch of the second bridge arm converter to be turned on and the lower bridge switch to be turned off, to form the electricity storage loop including the power battery, so that the windings of the first motor and the second motor are stored with electricity, and control the upper bridge switch of the first bridge arm converter to be turned on and the lower bridge switch to be turned off, the upper bridge switch of the second bridge arm converter to be turned off and the lower bridge switch to be turned on, to form the discharging loop including the power battery, so that the windings of the first motor and the second motor discharge electricity to the power battery.

[0075] Next, the current flow in the whole-pack heating mode according to one embodiment of the present disclosure is described with reference to FIGS. 4a and 4b.

[0076] In this embodiment, the first switch K1, the third switch K3, and the fourth switch K4 are turned on, and the second switch K2 is turned off, so that the power battery enters the whole-pack heating mode.

[0077] Referring to FIG. 4a, timing 1: the upper bridge arm of the second bridge arm converter 12 corresponding to the second motor 32 and the lower bridge arm of the first bridge arm converter 11 corresponding to the first motor 31 are turned on, the battery pack current passes through the upper bridge arm of the second bridge arm converter 12, the windings of the second motor 32 and the first motor 31, and the first switch K1, and flows back to the negative electrode of the battery pack through the lower bridge arm of the first bridge arm converter 11.

[0078] Referring to FIG. 4b, timing 2: the inductive windings on the second motor 32 and the first motor 31 continue to flow, the upper bridge arm of the first bridge arm converter 11 and the lower bridge arm of the second bridge arm converter 12 are turned on, the current on the inductive windings of the second motor 32 and the first motor 31 flows to the positive electrode of the battery pack through the upper bridge arm of the first bridge arm converter 11, and then flows to the negative electrode of the battery pack, and forms a loop with the second bridge arm converter 12 and the inductor.

[0079] Through the control of timing 1 and timing 2, the oscillation current of the whole battery pack can be formed, and the oscillation current generates a certain heat through the internal resistance of the battery pack.

[0080] It should be noted that the controller can also control the upper bridge switch tube of the first bridge arm converter to be turned on and the lower bridge switch tube to be turned off, the upper bridge switch tube of the second bridge arm converter to be turned off and the lower bridge switch tube to be turned on according to the preset second timing sequence, to form a power storage loop including the power battery, so that the windings of the first motor and the second motor are powered; and control the upper bridge switch tube of the first bridge arm converter to be turned off and the lower bridge switch tube to be turned on, the upper bridge switch tube of the second bridge arm converter to be turned on and the lower bridge switch tube to be turned off, to form a discharge loop including the power battery, so that the windings of the first motor and the second motor discharge the power battery.

[0081] According to one embodiment of the present disclosure, the heating control system further comprises a direct current charging interface, the first end of each phase bridge arm in the first bridge arm converter is connected to the positive electrode of the direct current charging interface, and the negative electrode of the direct current charging interface is connected to the second end of each phase bridge arm in the first bridge arm converter.

[0082] In one specific implementation, the direct current charging interface can be a charging gun interface. The positive electrode of the charging gun is connected to the first end of each phase bridge arm in the first bridge arm converter, and the negative electrode is connected to the second end of each phase bridge arm in the first bridge arm converter.

[0083] According to one embodiment of the present disclosure, the controller is further configured to control the first switch to be turned on and the second switch to be turned off, and control the upper bridge switch tube and the lower bridge switch tube of the first bridge arm converter and the second bridge arm converter to be turned on alternately according to a preset third timing sequence, to form a power storage loop including the power battery, so that the windings of the first motor and the second motor are powered, and to form a discharge loop including the direct current charging interface, so that the windings of the first motor and the second motor discharge the direct current charging interface.

[0084] Specifically, the controller can control the upper bridge switch tube of the first bridge arm converter to be turned off and the lower bridge switch tube to be turned on, the upper bridge switch tube of the second bridge arm converter to be turned on and the lower bridge switch tube to be turned off according to the preset third timing sequence, to form a power storage loop including the power battery, so that the windings of the first motor and the second motor are powered; and control the upper bridge switch tube of the first bridge arm converter to be turned on and the lower bridge switch tube to be turned off, the upper bridge switch tube of the second bridge arm converter to be turned off and the lower bridge switch tube to be turned on, to form a discharge loop including the direct current charging interface, so that the windings of the first motor and the second motor discharge the direct current charging interface.

[0085] Next, the current flow direction during the boost and buck discharge according to one embodiment of the present disclosure is described with reference to FIGS. 5a and 5b.

[0086] In this embodiment, the first switch K1, the third switch K3, the fourth switch K4, the fifth switch K5, and the sixth switch K6 are closed, so that the corresponding circuits are in the on state; and the second switch K2 is turned off.

[0087] Referring to FIG. 5a, timing 1: current flows through the upper bridge arm of the second bridge converter, flows through the first switch K1, flows through the lower bridge arm of the first bridge converter, and flows back to the negative electrode of the battery pack.

[0088] Referring to FIG. 5b, timing 2: inductance freewheels, flows through the first switch K1, flows through the anti-parallel diode of the upper bridge arm of the first bridge converter, flows to the positive electrode of the charging gun, then flows through the negative electrode of the charging gun, flows through the anti-parallel diode of the lower bridge arm of the second bridge converter, and flows back to the negative electrode of the inductance.

[0089] Timing 1 and timing 2 constitute a buck-boost circuit, by controlling the duty cycles of the upper bridge arm of the second bridge converter corresponding to the second motor and the lower bridge arm of the first bridge converter corresponding to the first motor, for example, when the duty cycle is 20%, the discharge voltage is less than the battery pack voltage, when the duty cycle is 50%, the discharge voltage is greater than the battery pack voltage. Therefore, adjusting the duty cycle of the control can realize the boost-buck discharge.

[0090] It should be noted that the controller can also control the upper bridge switch tube of the first bridge converter to be turned on and the lower bridge switch tube to be turned off, the upper bridge switch tube of the second bridge converter to be turned off and the lower bridge switch tube to be turned on according to a preset third timing, to form a power storage loop including the power battery, so that the windings of the first motor and the second motor are powered; and the upper bridge switch tube of the first bridge converter is turned off and the lower bridge switch tube is turned on, the upper bridge switch tube of the second bridge converter is turned on and the lower bridge switch tube is turned off, to form a discharge loop including the DC charging interface, so that the windings of the first motor and the second motor discharge the DC charging interface.

[0091] According to one embodiment of the present disclosure, the first end of each phase bridge arm in the first bridge converter is adapted to be connected to the positive electrode of the charging pile interface, and the second end of each phase bridge arm in the first bridge converter is adapted to be connected to the negative electrode of the charging pile interface.

[0092] According to one embodiment of the present disclosure, the controller is further configured to control the first switch to be turned on and the second switch to be turned off, and control the upper bridge switch tube and the lower bridge switch tube of the first bridge converter and the second bridge converter to be turned on alternately according to a preset fourth timing, to form a charging loop including the charging pile interface, so that the windings of the first motor and the second motor are powered, and to form a discharge loop including the power battery, so that the windings of the first motor and the second motor discharge the power battery.

[0093] Specifically, the controller can control the upper bridge switch tube of the first bridge arm converter to be turned on and the lower bridge switch tube to be turned off, and the upper bridge switch tube of the second bridge arm converter to be turned off and the lower bridge switch tube to be turned on according to a preset fourth timing, to form a charging loop including the charging pile interface, so that the windings of the first motor and the second motor are stored with electricity; and control the upper bridge switch tube of the first bridge arm converter to be turned off and the lower bridge switch tube to be turned on, and the upper bridge switch tube of the second bridge arm converter to be turned on and the lower bridge switch tube to be turned off, to form a discharging loop including the power battery, so that the windings of the first motor and the second motor discharge the power battery.

[0094] Next, the current flow direction during the boost and buck charging according to one embodiment of the present disclosure is described with reference to FIGS. 6a and 6b.

[0095] In this embodiment, the first switch K1, the third switch K3, the fourth switch K4, the seventh switch K7, and the eighth switch K8 are closed, so that the corresponding circuits are in a conductive state; and the second switch K2 is turned off.

[0096] Referring to FIG. 6a, timing 1: the current flows through the upper bridge arm of the first bridge arm converter, flows through the first switch K1, flows through the lower bridge arm of the second bridge arm converter, and flows back to the negative electrode of the charging pile.

[0097] Referring to FIG. 6b, timing 2: the inductor freewheels, flows through the first switch K1, flows through the anti-parallel diode of the upper bridge arm of the second bridge arm converter, flows to the positive electrode of the battery pack, flows through the negative electrode of the battery pack, and flows back to the negative electrode of the inductor through the anti-parallel diode of the lower bridge arm of the first bridge arm converter.

[0098] Timing 1 and timing 2 constitute a buck-boost circuit. By controlling the duty cycle of the upper bridge arm of the first bridge arm converter and the lower bridge arm of the second bridge arm converter, when the duty cycle is 20%, for example, the charging voltage is greater than the battery pack voltage, and when the duty cycle is 50%, the charging voltage is less than the battery pack voltage. Therefore, adjusting the duty cycle of the control can realize boost and buck charging.

[0099] In this embodiment, three motors are used to realize boost and buck discharging or charging, thereby improving the compatibility of the whole vehicle charging and enabling the whole vehicle to be compatible with more charging piles.

[0100] It should be noted that the controller can also control the first bridge arm converter according to the preset fourth timing to turn off the upper bridge switch tube and turn on the lower bridge switch tube, turn on the upper bridge switch tube and turn off the lower bridge switch tube of the second bridge arm converter, form a charging circuit including the charging pile interface, so that the windings of the first motor and the second motor store electricity; and control the upper bridge switch tube of the first bridge arm converter to turn on and the lower bridge switch tube to turn off, the upper bridge switch tube of the second bridge arm converter to turn off and the lower bridge switch tube to turn on, form a discharge circuit including the power battery, so that the windings of the first motor and the second motor discharge the power battery.

[0101] Next, a vehicle according to an embodiment of the present disclosure is described with reference to FIG. 7.

[0102] As shown in FIG. 7, the vehicle 700 provided by the present disclosure includes a power battery 710, a first motor 721, a second motor 722, a third motor 723, and the above-mentioned battery heating control system 730, wherein the power battery 710 includes a first battery module 711 and a second battery module 712 connected in series.

[0103] The vehicle realizes charging and discharging of the power battery through the motor windings in the three-motor drive system and the bridge arm converter in the battery heating control system, so that the battery generates heat during operation, thereby realizing battery heating. Moreover, the power battery is oscillated and heated by using the motor windings and the bridge arm converter inherent to the automobile, without the need for additional external equipment, which helps to save costs.

[0104] Although the example embodiments have been described herein with reference to the accompanying drawings, it is to be understood that the example embodiments are merely exemplary and are not intended to limit the scope of the present disclosure. Those of ordinary skill in the art can make various changes and modifications without departing from the scope and spirit of the present disclosure. All such changes and modifications are intended to be included within the scope of the present disclosure as claimed in the appended claims.

[0105] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in connection with the embodiments disclosed herein can be realized by electronic hardware, or a combination of computer software and electronic hardware. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Those of ordinary skill in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present disclosure.

[0106] In several embodiments provided in the present disclosure, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the above-described device embodiments are merely illustrative, and the division of the units is merely a logical function division. In actual implementation, another division manner can be used, for example, a plurality of units or components can be combined or integrated into another device, or some features can be omitted or not executed.

[0107] In the specification provided herein, a large number of specific details are described. However, it can be understood that the embodiments of the present disclosure can be practiced without these specific details. In some examples, well-known methods, structures, and techniques are not described in detail in order not to obscure the understanding of the present specification.

[0108] Similarly, it should be appreciated that, in the description of the exemplary embodiments of the present disclosure, various features of the present disclosure are sometimes grouped together in a single embodiment, figure, or description of a related aspect. However, this method of the present disclosure should not be interpreted as reflecting an intention that the claimed disclosure requires more features than are explicitly recited in each claim. Rather, it is intended that the disclosure of a single embodiment encompasses all features of that embodiment, and any one feature of a single embodiment can be combined with each of the features of any other disclosed embodiment. Thus, the following claims are hereby expressly incorporated into this detailed description, with each claim acting as a separate embodiment of the disclosure.

[0109] Those skilled in the art can understand that, except for the mutual exclusion between features, all features disclosed in the specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device disclosed in this way can be combined in any combination. Unless explicitly stated otherwise, each feature disclosed in the specification (including the accompanying claims, abstract, and drawings) can be replaced by an alternative feature that provides the same, equivalent, or similar purpose.

[0110] In addition, those skilled in the art can understand that, although some embodiments described herein include certain features rather than other features included in other embodiments, the combination of features of different embodiments means that it is within the scope of the present disclosure and forms different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0111] Various component embodiments of the present disclosure can be implemented in hardware, or as software modules running in one or more processors, or combinations thereof. Those skilled in the art will appreciate that some or all of the functionality of some of the modules in the item analysis apparatus according to embodiments of the present disclosure can be implemented in practice using a microprocessor or a digital signal processor (DSP). The present disclosure can also be implemented as a program for executing part or all of the methods described herein on a computer (for example, a computer program and a computer program product). Such a program implementing the present disclosure can be stored on a computer-readable medium, or can have the form of one or more signals. Such a signal can be downloaded from a website, or provided on a carrier signal, or provided in any other form.

[0112] It should be noted that the above-mentioned embodiments illustrate rather than limit the disclosure, and that one skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word 'comprising' does not exclude the presence of elements or steps not listed in a claim. The word 'a' or 'an' preceding an element does not exclude the presence of a plurality of such elements. The disclosure can be implemented by means of both hardware and software, and any combination thereof. In a unit claim, several devices can be listed with a conjunction like 'or', and a single element can be substituted therefor. The use of the word 'at least' followed by a list of one or more items does not exclude additional such items. The use of the words 'first','second' and 'third', etc., does not limit the scope of the claims, which comprise any one of the disclosed items apart from those specifically excluded in the claims.

[0113] The above description is only specific embodiments or specific implementations of the present disclosure, and the protection scope of the present disclosure is not limited thereto. Any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the present disclosure, and all such changes or replacements should be covered within the protection scope of the present disclosure. The protection scope of the present disclosure should be subject to the protection scope of the claims.

Claims

1. A battery heating control system, applied to a vehicle including a power battery, a first motor, a second motor, and a third motor, characterized in that, The heating control system includes: The system comprises a first bridge arm converter, a second bridge arm converter, a third bridge arm converter, and a controller. The first bridge arm converter is connected to the positive and negative terminals of the power battery and the windings of the first motor, respectively. The second bridge arm converter is connected to the positive and negative terminals of the power battery and the windings of the second motor, respectively. The third bridge arm converter is connected to the positive and negative terminals of the power battery and the windings of the third motor, respectively. The controller is connected to the first bridge arm converter, the second bridge arm converter, and the third bridge arm converter respectively, and is used to control the operation of at least one of the first bridge arm converter, the second bridge arm converter, and the third bridge arm converter, so that the power battery charges and / or discharges at least one winding of the first motor, the second motor, and the third motor to achieve heating of the power battery.

2. The battery heating control system as described in claim 1, characterized in that, The heating control system further includes a first switch and a second switch. The power battery includes a first battery module and a second battery module connected in series. The neutral point of the first motor is connected to the neutral point of the second motor through the first switch. The neutral point of the third motor is connected to the connection point of the first battery module and the second battery module through the second switch.

3. The battery heating control system as described in claim 2, characterized in that, The controller is connected to the control ports of the first switch and the second switch respectively, and is used to control the first switch to be open and the second switch to be closed, so that the power battery enters the module heating mode; or, control the first switch to be closed and the second switch to be open, so that the power battery enters the whole pack heating mode.

4. The battery heating control system as described in claim 3, characterized in that, When the power battery enters the module heating mode, the controller is also used to control the upper bridge switch and the lower bridge switch of the third bridge arm converter to be turned on alternately according to a preset first timing sequence, forming a power storage circuit including the first battery module or the second battery module, so that the winding of the third motor stores power; and forming a discharge circuit including the second battery module or the first battery module, so that the winding of the third motor discharges to the second battery module or the first battery module.

5. The battery heating control system as described in claim 3 or 4, characterized in that, When the power battery enters the whole pack heating mode, the controller is also used to control the upper bridge switch and lower bridge switch of the first bridge arm converter and the second bridge arm converter to be turned on alternately according to a preset second timing sequence, so as to form a power storage circuit including the power battery, so as to enable the windings of the first motor and the second motor to store electricity, and to form a discharge circuit including the power battery, so as to enable the windings of the first motor and the second motor to discharge the power battery.

6. The battery heating control system according to any one of claims 2-5, characterized in that, The heating control system further includes a DC charging interface, wherein the first end of each phase arm in the first bridge arm converter is connected to the positive terminal of the DC charging interface, and the negative terminal of the DC charging interface is connected to the second end of each phase arm in the first bridge arm converter.

7. The battery heating control system as described in claim 6, characterized in that, The controller is also used to control the first switch to be turned on and the second switch to be turned off, and to control the upper bridge switch and lower bridge switch of the first bridge arm converter and the second bridge arm converter to be turned on alternately according to a preset third timing sequence, so as to form a power battery-included energy storage circuit, so as to enable the windings of the first motor and the second motor to store energy, and to form a discharge circuit including the DC charging interface, so as to enable the windings of the first motor and the second motor to discharge to the DC charging interface.

8. The battery heating control system according to any one of claims 2-7, characterized in that, In the first bridge arm converter, the first end of each phase bridge arm is adapted to be connected to the positive terminal of the charging pile interface, and the second end of each phase bridge arm is adapted to be connected to the negative terminal of the charging pile interface.

9. The battery heating control system as described in claim 8, characterized in that, The controller is also used to control the first switch to be turned on and the second switch to be turned off, and to control the upper bridge switch and lower bridge switch of the first bridge arm converter and the second bridge arm converter to be turned on alternately according to a preset fourth timing sequence, so as to form a charging circuit including the charging pile interface, so as to enable the windings of the first motor and the second motor to store electricity, and to form a discharging circuit including the power battery, so as to enable the windings of the first motor and the second motor to discharge the power battery.

10. The battery heating control system according to any one of claims 2-9, characterized in that, The first bridge arm converter, the second bridge arm converter, and the third bridge arm converter each include N phase bridge arms arranged in parallel. Each phase bridge arm includes an upper bridge switch and a lower bridge switch. The first end of each phase bridge arm is connected to the positive terminal of the power battery, and the second end of each phase bridge arm is connected to the negative terminal of the power battery. Wherein, N is a positive integer greater than or equal to 1.

11. The battery heating control system as described in claim 10, characterized in that, The first bridge arm converter, the second bridge arm converter, and the third bridge arm converter each include three-phase bridge arms connected in parallel.

12. The battery heating control system as described in claim 10, characterized in that, The upper bridge switch and the lower bridge switch each include an insulated gate bipolar transistor and a parallel reverse diode.

13. The battery heating control system according to any one of claims 10-12, characterized in that, The first motor, the second motor, and the third motor each include N-phase winding coils. The midpoint of each phase bridge arm is connected to the first end of a phase winding coil, and the second ends of the N-phase winding coils are connected to each other to form the neutral point of each motor.

14. The battery heating control system as described in claim 13, characterized in that, The first motor, the second motor and the third motor each include a three-phase winding coil.

15. A vehicle, characterized in that, It includes a power battery, a first motor, a second motor, a third motor, and a heating control system for the battery as described in any one of claims 1-14.

16. The vehicle as claimed in claim 15, characterized in that, The power battery includes a first battery module and a second battery module connected in series.

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