Charging and discharging system, control method, computer storage medium and vehicle

Abstract

The invention relates to a charging and discharging system, a control method, a computer storage medium and a vehicle, the charging and discharging system comprises a battery, a super capacitor and a bidirectional converter, the positive electrode of the battery is connected with the positive electrode of external charging equipment, and the positive electrode of the battery is connected with the positive electrode of the low-voltage side of the bidirectional converter; the positive electrode of the super capacitor is connected with the positive electrode of the high-voltage side of the bidirectional converter, and the connection point of the super capacitor and the positive electrode of the high-voltage side of the bidirectional converter is connected to the positive electrode of external electric equipment, and the negative electrode of the super capacitor is connected with the negative electrode of the high-voltage side of the bidirectional converter, and the connection point of the super capacitor and the negative electrode of the high-voltage side of the bidirectional converter is connected to the negative electrode of the external electric equipment; and the high-voltage side cathode of the bidirectional converter is also connected with the cathode of external charging equipment. The technical problem that high-power response and high-energy reserve are difficult to realize in the prior art can be solved.

Description

Technical Field

[0001] This application relates to the field of vehicle engineering technology, and in particular to a charging and discharging system, control method, computer storage medium, and vehicle. Background Technology

[0002] In the power systems of new energy vehicles, supercapacitors are often used as auxiliary power sources due to their high power density and long cycle life, especially in transient high-power scenarios such as rapid vehicle acceleration and regenerative braking. However, the inherent limitation of low energy density in supercapacitors means they cannot independently meet the continuous power supply needs of the entire vehicle and must be used in combination with batteries.

[0003] Existing technologies typically employ a scheme where lithium batteries serve as the primary power source, with supercapacitors providing auxiliary power supplementation. For example, by connecting the two via a bidirectional converter, the lithium battery directly drives the vehicle and handles regular charging and discharging tasks, while the supercapacitor only intervenes to supplement power when the lithium battery power is insufficient or energy recovery exceeds limits.

[0004] However, while the above solutions can alleviate instantaneous power pressure, lithium batteries still need to balance energy supply and high power response, limiting the application scope of high-energy-density batteries. Specifically, if high-power lithium batteries are used, the energy density decreases, limiting the driving range; if high-energy-density lithium batteries are used, their power bottleneck requires larger supercapacitors and higher-power converters to compensate, increasing system costs and reducing efficiency. Summary of the Invention

[0005] This application provides a charging and discharging system, a control method, a computer storage medium, and a vehicle, aiming to improve the technical problem that it is difficult to achieve high power response and high energy storage in the prior art.

[0006] This application first provides a charging and discharging system, including a battery, a supercapacitor, and a bidirectional converter. The positive terminal of the battery is connected to the positive terminal of an external charging device and the positive terminal of the battery is connected to the low-voltage side of the bidirectional converter. The negative terminal of the battery is connected to the low-voltage side of the bidirectional converter. The positive terminal of the supercapacitor is connected to the high-voltage side of the bidirectional converter, and the connection point between the positive terminal of the supercapacitor and the high-voltage side of the bidirectional converter is connected to the positive terminal of the external electrical device. The negative terminal of the supercapacitor is connected to the high-voltage side of the bidirectional converter, and the connection point between the negative terminal of the supercapacitor and the high-voltage side of the bidirectional converter is connected to the negative terminal of the external electrical device. The high-voltage side of the bidirectional converter is also connected to the negative terminal of the external charging device.

[0007] In the charging and discharging system of this application, the supercapacitor is directly connected to external electrical equipment (such as a drive motor) and receives power from the battery through a bidirectional converter. The battery is connected to the charging equipment and the low-voltage side of the bidirectional converter, allowing the supercapacitor to become a direct energy output source for the drive end, fully releasing its high power density characteristics to respond to transient load demands. The battery, as a dedicated energy storage unit, maintains the supercapacitor's charge through the bidirectional converter, such as maintaining the supercapacitor's charge with a relatively low power. In this case, the supercapacitor's high power output capability can reduce the impact of large currents on the battery during charging and discharging, allowing the selection of a pure high-energy-density battery model, thereby enabling the system to achieve high power response and high energy storage.

[0008] In some embodiments, the device further includes a control device, a first switch, a second switch, and a third switch. The first switch is disposed between the positive terminal of the battery and the positive terminal of the external charging device. The second switch is disposed between the positive terminal of the battery and the low-voltage side positive terminal of the bidirectional converter. The third switch is disposed between the connection point of the positive terminal of the supercapacitor and the high-voltage side positive terminal of the bidirectional converter and the positive terminal of the external electrical device.

[0009] In some embodiments, when the voltage value of the supercapacitor is less than or equal to a first preset voltage value, the control device controls the first switch and the second switch to close and controls the third switch to open, and controls the bidirectional converter to operate in the first mode so that the battery supplies power to the supercapacitor at maximum power; when the voltage value of the supercapacitor is greater than the first preset voltage value, the control device controls the second switch and the third switch to close and controls the first switch to open, and controls the bidirectional converter to operate in the second mode so that the battery supplies power to the supercapacitor at multiple preset power levels, and the supercapacitor supplies power to external electrical equipment, wherein the preset power is less than the maximum power and the multiple preset power levels decrease sequentially, and the second mode corresponds to the multiple preset power levels being divided into multiple sub-modes.

[0010] In some embodiments, the control device controls the opening and closing of the first switch, the second switch, and the third switch, as well as the operating mode of the bidirectional converter, based on the battery's charge level, so that the battery can acquire and store electrical energy through an external charging device, and when the charge level is greater than a preset charge level, it supplies power to the supercapacitor through the bidirectional converter.

[0011] In some embodiments, when the battery charge is less than or equal to a preset charge, the control device controls the first and second switches to close and controls the bidirectional converter to operate in a third mode, so that the battery can acquire and store electrical energy through an external charging device; when the battery charge is greater than the preset charge, the control device controls the first and second switches to close and controls the bidirectional converter to operate in a fourth mode, so that the battery can acquire and store electrical energy through an external charging device, and supplies power to the supercapacitor at a fixed current value through the bidirectional converter; when the battery charge is greater than the preset charge and the voltage of the supercapacitor is greater than or equal to a second preset voltage value, the control device controls the first and second switches to close and controls the bidirectional converter to operate in a third mode, so that the battery can acquire and store electrical energy through an external charging device, and stops supplying power to the supercapacitor at a fixed current value through the bidirectional converter; wherein, the second preset voltage value is greater than the first preset voltage value.

[0012] In some embodiments, the positive terminal of the battery is also connected to the positive terminal of an external electrical device, and a first switch is disposed between the positive terminal of the battery and the positive terminal of the external electrical device. When the charge is less than or equal to a preset charge, the control device controls the first and second switches to close and the third switch to open, and controls the bidirectional converter to operate in the third mode, so that the battery can obtain and store electrical energy through an external charging device. When the charge is greater than the preset charge, the control device controls the first and second switches to close and the third switch to open, and controls the bidirectional converter to operate in the fourth mode, so that the battery can obtain and store electrical energy through an external charging device, and supplies power to the supercapacitor at a fixed current value through the bidirectional converter. When the charge is greater than the preset charge and the voltage of the supercapacitor is greater than or equal to a second preset voltage value, the control device controls the first and second switches to close and the third switch to open, and controls the bidirectional converter to operate in the third mode, so that the battery can obtain and store electrical energy through an external charging device, and stops supplying power to the supercapacitor at a fixed current value through the bidirectional converter. The second preset voltage value is greater than the first preset voltage value.

[0013] This application also provides a charging and discharging control method, applied to the charging and discharging system of any of the above embodiments of this application. The control method includes: acquiring the voltage value of a supercapacitor, controlling the opening and closing of multiple switches and the working mode of a bidirectional converter based on the voltage value of the supercapacitor, so that the supercapacitor receives power from the battery through the bidirectional converter and provides electrical energy to external electrical devices; acquiring the battery's charge level, controlling the opening and closing of multiple switches and the working mode of the bidirectional converter based on the battery's charge level, so that the battery acquires and stores electrical energy through an external charging device, and when the charge level is greater than a preset charge level, supplies power to the supercapacitor through the bidirectional converter.

[0014] In the charging and discharging control method of this application, firstly, by monitoring the supercapacitor voltage and switching the switching state and converter operating mode, the supercapacitor is always kept in a high-efficiency discharge window, fully releasing its high power density advantage to respond to transient conditions such as acceleration and braking, and reducing drive interruptions caused by voltage drops. Secondly, by acquiring battery power information in real time, hierarchical management is implemented during the charging phase: when the battery power is low, the battery's stored energy is injected in a concentrated manner; when the battery power is high, a portion of the energy is diverted to the supercapacitor via the converter, maintaining its standby state without affecting the battery charging progress. This achieves automatic coordination of the charging priority and energy distribution between the supercapacitor and the battery. With the battery as the main energy reserve and the supercapacitor as a dynamic buffer unit and the main high-power output unit, the system can overcome the limitation that high power and high energy density cannot be simultaneously achieved.

[0015] In some embodiments, the opening and closing of multiple switches and the operating mode of the bidirectional converter are controlled based on the voltage value of the supercapacitor, so that the supercapacitor receives power from the battery through the bidirectional converter and provides electrical energy to external electrical devices. This includes: when the voltage value of the supercapacitor is less than or equal to a first preset voltage value, controlling the first switch and the second switch to close and the third switch to open, and controlling the operating mode of the bidirectional converter to a first mode, so that the battery supplies power to the supercapacitor at maximum power; when the voltage value of the supercapacitor is greater than the first preset voltage value, controlling the second switch and the third switch to close and the first switch to open, and controlling the operating mode of the bidirectional converter to a second mode, so that the battery supplies power to the supercapacitor at multiple preset power levels, and the supercapacitor provides electrical energy to external electrical devices; wherein the preset power is less than the maximum power and the multiple preset power levels decrease sequentially, and the second mode corresponds to multiple sub-modes corresponding to the multiple preset power levels.

[0016] In some embodiments, the opening and closing of multiple switches and the operating mode of a bidirectional converter are controlled based on the battery's charge level, so that the battery can acquire and store electrical energy through an external charging device, and supply power to a supercapacitor through the bidirectional converter when the charge level is greater than a preset charge level. This includes: when the charge level is less than or equal to the preset charge level, controlling the first and second switches to close and controlling the bidirectional converter to operate in a third mode, so that the battery can acquire and store electrical energy through an external charging device; when the charge level is greater than the preset charge level, controlling the first and second switches to close and controlling the bidirectional converter to operate in a fourth mode, so that the battery can acquire and store electrical energy through an external charging device, and supply power to the supercapacitor at a fixed current value through the bidirectional converter; when the charge level is greater than the preset charge level and the voltage of the supercapacitor is greater than or equal to a second preset voltage value, controlling the first and second switches to close and controlling the bidirectional converter to operate in a third mode, so that the battery can acquire and store electrical energy through an external charging device, and stopping the supply of power to the supercapacitor at a fixed current value through the bidirectional converter; wherein the second preset voltage value is greater than the first preset voltage value.

[0017] In some embodiments, the opening and closing of multiple switches and the operating mode of a bidirectional converter are controlled based on the battery's charge level, so that the battery can acquire and store electrical energy through an external charging device, and supply power to a supercapacitor through the bidirectional converter when the charge level is greater than a preset charge level. This includes: when the charge level is less than or equal to the preset charge level, controlling the first and second switches to close and the third switch to open, and controlling the bidirectional converter to operate in a third mode, so that the battery can acquire and store electrical energy through an external charging device; when the charge level is greater than the preset charge level, controlling the first and second switches to close and the third switch to open, and controlling the bidirectional converter to operate in a fourth mode, so that the battery can acquire and store electrical energy through an external charging device, and supply power to the supercapacitor through the bidirectional converter at a fixed current value; when the charge level is greater than the preset charge level and the voltage of the supercapacitor is greater than or equal to a second preset voltage value, controlling the first and second switches to close and the third switch to open, and controlling the bidirectional converter to operate in the third mode, so that the battery can acquire and store electrical energy through an external charging device, and stopping the supply of power to the supercapacitor through the bidirectional converter at a fixed current value; wherein the second preset voltage value is greater than the first preset voltage value.

[0018] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the charging and discharging control method of any of the above embodiments of this application.

[0019] This application also provides a vehicle including a charging and discharging system according to any of the above embodiments of this application. The charging and discharging system includes a control device for executing the charging and discharging control method according to any of the above embodiments of this application. Attached Figure Description

[0020] Figure 1 This is a circuit diagram of the charging and discharging system according to an embodiment of this application.

[0021] Figure 2 This is a circuit diagram of a charging and discharging system according to another embodiment of this application.

[0022] Figure 3 This is a circuit diagram of a charging and discharging system according to another embodiment of this application.

[0023] Figure 4 This is a flowchart of the charging and discharging control method according to an embodiment of this application.

[0024] Figure 5 This is a sub-flowchart of step S200 in an embodiment of this application.

[0025] Figure 6 This is a sub-flowchart of step S500 in an embodiment of this application.

[0026] Figure 7 This is another sub-flowchart of step S500 in an embodiment of this application.

[0027] Figure 8 This is a schematic diagram showing the relationship between the voltage threshold of the supercapacitor and the operating mode of the bidirectional converter in an embodiment of this application.

[0028] Figure 9 This is a schematic diagram showing the relationship between the battery power threshold and the operating mode of the bidirectional converter in an embodiment of this application.

[0029] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this application. Detailed Implementation

[0030] To make the technical problems, technical solutions, and beneficial effects solved by this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0031] This application provides a charging and discharging system, a control method, a computer storage medium, and a vehicle, aiming to address the technical problem of achieving high power response and high energy storage in the prior art. Some embodiments will be described below with reference to the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other. It should be noted that the accompanying drawings... Figure 1 To be continued Figure 3 In the diagram, solid lines indicate circuit connections, while dashed lines indicate communication connections.

[0032] Figure 1 This is a circuit schematic diagram of the charging and discharging system 100 according to an embodiment of this application.

[0033] like Figure 1 As shown, this application first provides a charging and discharging system 100, which can be applied in vehicles. For ease of description, it can also be referred to as "System 100" below. Figure 1As shown, the charging and discharging system 100 may include a battery 10, a supercapacitor 11, and a bidirectional converter 12. The positive terminal of the battery 10 is connected to the positive terminal of the external charging device 20 and the low-voltage positive terminal of the bidirectional converter 12. The negative terminal of the battery 10 is connected to the low-voltage negative terminal of the bidirectional converter 12. The positive terminal of the supercapacitor 11 is connected to the high-voltage positive terminal of the bidirectional converter 12, and the connection point between the positive terminal of the supercapacitor 11 and the high-voltage positive terminal of the bidirectional converter 12 is connected to the positive terminal of the external electrical device 30. The negative terminal of the supercapacitor 11 is connected to the high-voltage negative terminal of the bidirectional converter 12, and the connection point between the negative terminal of the supercapacitor 11 and the high-voltage negative terminal of the bidirectional converter 12 is connected to the negative terminal of the external electrical device 30. The high-voltage negative terminal of the bidirectional converter 12 is also connected to the negative terminal of the external charging device 20.

[0034] In some embodiments, the bidirectional converter 12 is a bidirectional DC-DC converter.

[0035] In this embodiment, the supercapacitor 11 can be configured to receive power from the battery 10 via a bidirectional converter 12 and supply power to the external electrical device 30. The battery 10 can be configured to acquire and store power through an external charging device 20, and supply power to the supercapacitor 11 via the bidirectional converter 12 when the power level exceeds a preset level. In this case, the supercapacitor 11 is directly connected to the external electrical device 30 (such as a drive motor) and receives power from the battery 10 via the bidirectional converter 12. The battery 10 is connected to the charging device and the low-voltage side of the bidirectional converter 12, which allows the supercapacitor 11 to become a direct energy output source for the drive end, fully releasing its high power density characteristics to respond to transient load demands. The battery 10 serves as a dedicated energy storage unit, maintaining the power level of the supercapacitor 11 via the bidirectional converter 12, such as maintaining the power level of the supercapacitor 11 with a lower power. In this case, the high power output capability of the supercapacitor 11 can reduce the impact of large currents on the battery 10 during charging and discharging, allowing the battery 10 to be selected as a pure high-energy-density model, thereby enabling the system 100 to achieve high power response and high energy storage.

[0036] In some embodiments, such as Figure 1As shown, the charging and discharging system 100 may further include a control device 18, a first switch 13, a second switch 14, and a third switch 15. The first switch 13 is located between the positive terminal of the battery 10 and the positive terminal of the external charging device 20; the second switch 14 is located between the positive terminal of the battery 10 and the low-voltage side positive terminal of the bidirectional converter 12; and the third switch 15 is located between the connection point of the positive terminal of the supercapacitor 11 and the high-voltage side positive terminal of the bidirectional converter 12 and the positive terminal of the external electrical device 30. The control device 18 is configured to control the opening and closing of the first switch 13, the second switch 14, and the third switch 15, as well as the operating mode of the bidirectional converter 12, based on the voltage value of the supercapacitor 11, so that the supercapacitor 11 receives power from the battery 10 through the bidirectional converter 12 and provides electrical energy to the external electrical device 30. In this case, the energy path can be switched by combining multiple switches and bidirectional converters 12, so that the system 100 can flexibly respond to the state of the supercapacitor 11 (such as power failure or sufficient power), ensuring the continuity of power supply of the supercapacitor 11, thereby maintaining the supercapacitor 11 as the core for providing power to external electrical equipment 30 in steady state.

[0037] In this embodiment, specifically, when the voltage of the supercapacitor 11 is less than or equal to a first preset voltage value, the control device 18 controls the first switch 13 and the second switch 14 to close and controls the third switch 15 to open, and controls the bidirectional converter 12 to operate in the first mode, so that the battery 10 supplies power to the supercapacitor 11 at maximum power; when the voltage of the supercapacitor 11 is greater than the first preset voltage value, the control device 18 controls the second switch 14 and the third switch 15 to close and controls the first switch 13 to open, and controls the bidirectional converter 12 to operate in the second mode, so that the battery 10 supplies power to the supercapacitor 11 at multiple preset power levels, and the supercapacitor 11 provides power to the external electrical equipment 30, wherein the preset power is less than the maximum power and the multiple preset power levels decrease sequentially, and the second mode corresponds to the multiple preset power levels being divided into multiple sub-modes. In this scenario, the energy storage capacity of supercapacitor 11 is maximized during emergency power replenishment. During normal operation, optimized power matching the actual load is adopted (e.g., medium power maintenance during high load and low power maintenance during light load) to reduce energy waste. In other words, by using multi-level power division, the voltage of supercapacitor 11 is stabilized within the efficient operating window, which can ensure the quality of the drive voltage and reduce converter losses, thereby achieving refined control of power management.

[0038] In some embodiments, the control device 18 is further configured to: control the opening and closing of the first switch 13, the second switch 14, and the third switch 15, as well as the operating mode of the bidirectional converter 12, based on the battery 10's power level, so that the battery 10 can acquire and store electrical energy through the external charging device 20, and supply power to the supercapacitor 11 through the bidirectional converter 12 when the power level is greater than a preset power level. In this case, since the capacity of the supercapacitor 11 is much smaller than that of the battery 10, its charging process is fast and does not affect the charging progress of the battery 10. By prioritizing the charging efficiency of the core energy storage unit (i.e., the battery 10), and diverting some energy to gently replenish the supercapacitor 11 after the battery 10 has sufficient reserves, the coordinated charging optimization of the supercapacitor 11 and the battery 10 can be achieved.

[0039] In this embodiment, specifically, when the battery power is less than or equal to a preset battery power, the control device 18 controls the first switch 13 and the second switch 14 to close and controls the bidirectional converter 12 to operate in a third mode, so that the battery 10 can obtain and store electrical energy through the external charging device 20; when the battery power is greater than the preset battery power, the control device 18 controls the first switch 13 and the second switch 14 to close and controls the bidirectional converter 12 to operate in a fourth mode, so that the battery 10 can obtain and store electrical energy through the external charging device 20, and supplies power to the supercapacitor 11 with a fixed current value through the bidirectional converter 12; when the battery power is greater than the preset battery power and the voltage of the supercapacitor 11 is greater than or equal to a second preset voltage value, the control device 18 controls the first switch 13 and the second switch 14 to close and controls the bidirectional converter 12 to operate in a third mode, so that the battery 10 can obtain and store electrical energy through the external charging device 20, and stops supplying power to the supercapacitor 11 with a fixed current value through the bidirectional converter 12; wherein, the second preset voltage value is greater than the first preset voltage value. In this scenario, when the battery is low, the external charging device 20 charges the battery 10; when the battery is high, the battery 10 continuously supplies power to the supercapacitor 11; after the supercapacitor 11 reaches its upper limit voltage, it switches back to the third mode. The mode switching mechanism can reduce the risk of overcharging the supercapacitor 11. Furthermore, the decoupled charging management of the battery 10 and the supercapacitor 11 can reduce the additional losses introduced by the bidirectional converter 12 in the charging link, thereby improving the overall energy efficiency of the system 100.

[0040] Figure 2 This is a circuit diagram of a charging and discharging system 100 according to another embodiment of this application.

[0041] In some embodiments, such as Figure 2As shown, the positive terminal of battery 10 can also be connected to the positive terminal of external electrical device 30, and the first switch 13 is disposed between the positive terminal of battery 10 and the positive terminal of external electrical device 30. When the power is less than or equal to the preset power, the control device 18 controls the first switch 13 and the second switch 14 to close and controls the third switch 15 to open, and controls the bidirectional converter 12 to operate in the third mode, so that battery 10 can obtain and store electrical energy through external charging device 20; when the power is greater than the preset power, the control device 18 controls the first switch 13 and the second switch 14 to close and controls the third switch 15 to open, and controls the bidirectional converter 12 to operate in the fourth mode, so that battery 10 can obtain and store electrical energy through external charging device 20. The bidirectional converter 12 supplies power to the supercapacitor 11 at a fixed current value. When the charge is greater than the preset charge and the voltage of the supercapacitor 11 is greater than or equal to the second preset voltage value, the control device 18 controls the first switch 13 and the second switch 14 to close and controls the third switch 15 to open, and controls the working mode of the bidirectional converter 12 to the third mode, so that the battery 10 can obtain and store electrical energy through the external charging device 20, and stops supplying power to the supercapacitor 11 at a fixed current value through the bidirectional converter 12; wherein, the second preset voltage value is greater than the first preset voltage value.

[0042] like Figure 1 and Figure 2 As shown, it can be seen that Figure 1 Examples and Figure 2 The difference in this embodiment is that the positive terminal of battery 10 can also be connected to the positive terminal of external electrical device 30. In this case, when supercapacitor 11 fails and battery 10 has sufficient power, system 100 disconnects the third switch 15 (the main path of supercapacitor 11) and closes the first switch 13 and the second switch 14, allowing battery 10 to directly take over the driving task. That is, a physical bypass channel can be constructed when supercapacitor 11 fails. Battery 10 achieves the dual functions of driving and synchronously replenishing power to supercapacitor 11 through an independent link, thereby enhancing the fault tolerance of system 100 and improving the reliability of system 100.

[0043] Figure 3 This is a circuit diagram of a charging and discharging system 100 according to another embodiment of this application.

[0044] In some embodiments, such as Figure 3As shown, the charging and discharging system 100 may further include a fourth switch 16 and a fifth switch 17. The fourth switch 16 is located between the first switch 13 and the external electrical device 30, and also between the third switch 15 and the external electrical device 30. The fifth switch 17 is connected in series with a resistor 19 and then in parallel with the fourth switch 16. The fourth switch 16 is used to connect the battery 10 or the supercapacitor 11 to the external electrical device 30 when it is powered on. The fifth switch 17 and the resistor 19 are used to precharge the external electrical device 30 when it is powered on. In this case, the circuit safety can be ensured when the battery 10 is in direct drive mode (such as in an emergency situation where the supercapacitor 11 fails) or when the supercapacitor 11 is in main power supply mode, reducing the burning of various relay contacts in the circuit, and protecting sensitive devices such as the bidirectional converter 12 from current surges. In addition, the precharging function of the fifth switch 17 and the resistor 19 works in conjunction with the original switch network (i.e., the first switch 13 to the fourth switch 16) and the control device 18, which can further enhance the robustness of the system 100 under abnormal operating conditions.

[0045] In some embodiments, such as Figure 1 , Figure 2 or Figure 3 As shown, the external charging device 20 can be connected to the charging and discharging system 100 through the charging interface 101, and a protective element (such as a diode) can be provided in the charging interface 101; the external electrical device 30 can be connected to the charging and discharging system 100 through the discharging interface 102; the charging and discharging system 100 can also be provided with a communication interface 103; such as Figure 3 As shown, the control device 18 may include a first control device 181 for battery power management and for controlling the aforementioned switches, and a second control device 182 for supercapacitor power management. The control device 18 may be a BMS. For ease of distinction, the first control device 181 is referred to as the main BMS, and the second control device 182 is referred to as the auxiliary BMS.

[0046] In some embodiments, the external charging device 20 may be a charger or a charging pile device, and the external electrical device 30 may be the vehicle's drive motor.

[0047] Figure 4 This is a flowchart of the charging and discharging control method according to an embodiment of this application.

[0048] Based on the above, such as Figure 4 As shown, this application also provides a charge / discharge control method, applied to the charge / discharge system of any of the above embodiments of this application. For ease of description, the charge / discharge control method may also be referred to as "control method" or "method" below. Figure 4 As shown, the control methods include: Step S100: Obtain the voltage value of the supercapacitor.

[0049] Step S200: Control the opening and closing of multiple switches and the operating mode of the bidirectional converter based on the voltage value of the supercapacitor.

[0050] Step S300: The supercapacitor receives power from the battery through the bidirectional converter and supplies power to external electrical devices.

[0051] Step S400: Obtain the battery power.

[0052] Step S500: Control the opening and closing of multiple switches and the operating mode of the bidirectional converter based on the battery power level.

[0053] Step S600: The battery acquires and stores electrical energy through an external charging device, and when the charge is greater than the preset charge, it supplies power to the supercapacitor through a bidirectional converter.

[0054] In the charging and discharging control method of this application, firstly, by monitoring the supercapacitor voltage and switching the switching state and converter operating mode, the supercapacitor is always kept in a high-efficiency discharge window, fully releasing its high power density advantage to respond to transient conditions such as acceleration and braking, and reducing drive interruptions caused by voltage drops. Secondly, by acquiring battery power information in real time, hierarchical management is implemented during the charging phase: when the battery power is low, the battery's stored energy is injected in a concentrated manner; when the battery power is high, a portion of the energy is diverted to the supercapacitor via the converter, maintaining its standby state without affecting the battery charging progress. This achieves automatic coordination of the charging priority and energy distribution between the supercapacitor and the battery. With the battery as the main energy reserve and the supercapacitor as a dynamic buffer unit and the main high-power output unit, the system can overcome the limitation that high power and high energy density cannot be simultaneously achieved.

[0055] Figure 5 This is a sub-flowchart of step S200 in an embodiment of this application. Figure 6 This is a sub-flowchart of step S500 in an embodiment of this application.

[0056] In some embodiments, such as Figure 5 As shown, the operation of multiple switches and the bidirectional converter is controlled based on the voltage value of the supercapacitor, i.e., step S200 may include: Sub-step S201: When the voltage value of the supercapacitor is less than or equal to the first preset voltage value, control the first switch and the second switch to close and control the third switch to open, and control the bidirectional converter to operate in the first mode.

[0057] Sub-step S201 allows the battery to supply power to the supercapacitor at maximum power in step S300.

[0058] Sub-step S202: When the voltage value of the supercapacitor is greater than the first preset voltage value, control the second switch and the third switch to close and control the first switch to open, and control the bidirectional converter to operate in the second mode.

[0059] Sub-step S202 allows the battery to supply power to the supercapacitor at multiple preset power levels in step S300, and the supercapacitor to supply power to external electrical devices.

[0060] Among them, the preset power is less than the maximum power and multiple preset powers decrease sequentially. The second mode corresponds to multiple preset powers and is divided into multiple sub-modes.

[0061] In some embodiments, such as Figure 6 As shown, the opening and closing of multiple switches and the operating mode of the bidirectional converter are controlled based on the battery power level. Step S500 may include: Sub-step S501: When the power is less than or equal to the preset power, control the first switch and the second switch to close, and control the bidirectional converter to operate in the third mode.

[0062] Sub-step S501 allows the battery to acquire and store electrical energy through an external charging device in step S600.

[0063] Sub-step S502: When the power is greater than the preset power, control the first switch and the second switch to close, and control the bidirectional converter to operate in the fourth mode.

[0064] Sub-step S502 allows the battery to acquire and store electrical energy through an external charging device in step S600, and supplies power to the supercapacitor with a fixed current value through a bidirectional converter.

[0065] Sub-step S503: When the charge is greater than the preset charge and the voltage of the supercapacitor is greater than or equal to the second preset voltage value, control the first switch and the second switch to close, and control the bidirectional converter to operate in the third mode.

[0066] Sub-step S503 allows the battery to acquire and store electrical energy through an external charging device in step S600, and stops supplying power to the supercapacitor at a fixed current value through the bidirectional converter.

[0067] The second preset voltage value is greater than the first preset voltage value.

[0068] Figure 7 This is another sub-flowchart of step S500 in an embodiment of this application. It can be understood that, as described above... Figure 2In the illustrated embodiment, the positive terminal of the battery can also be connected to the positive terminal of an external electrical device. To ensure that the battery preferentially obtains power from the external charging device and prevents the power from the external charging device from directly connecting to the supercapacitor, it is necessary to constrain and control the aforementioned switch network (such as the third switch). That is, in some other embodiments, the opening and closing of multiple switches and the operating mode of the bidirectional converter are controlled based on the battery's power level, so that the battery obtains and stores power through the external charging device, and when the power level is greater than a preset power level, it supplies power to the supercapacitor through the bidirectional converter. That is, step S500 may include: Sub-step S511: When the power is less than or equal to the preset power, control the first switch and the second switch to close and control the third switch to open, and control the bidirectional converter to operate in the third mode.

[0069] Sub-step S511 allows the battery to acquire and store electrical energy through an external charging device in step S600.

[0070] Sub-step S512: When the power is greater than the preset power, control the first switch and the second switch to close and control the third switch to open, and control the bidirectional converter to operate in the fourth mode.

[0071] Sub-step S512 allows the battery to acquire and store electrical energy through an external charging device in step S600, and supplies power to the supercapacitor with a fixed current value through a bidirectional converter.

[0072] Sub-step S513: When the power is greater than the preset power and the voltage of the supercapacitor is greater than or equal to the second preset voltage value, control the first switch and the second switch to close and control the third switch to open, and control the bidirectional converter to operate in the third mode.

[0073] Sub-step S513 allows the battery to acquire and store electrical energy through an external charging device in step S600, and stops supplying power to the supercapacitor at a fixed current value through the bidirectional converter.

[0074] The second preset voltage value is greater than the first preset voltage value.

[0075] Figure 8 This is a schematic diagram showing the relationship between the voltage threshold of the supercapacitor 11 and the operating mode of the bidirectional converter 12 in an embodiment of this application.

[0076] To describe in detail the charging and discharging methods of steps S100 to S300, a specific discharging process is provided: [Combined with...] Figure 8When the main BMS is woken up, if the main BMS (i.e., the first control device 181) detects that the current voltage of the supercapacitor 11 is less than the minimum voltage of the external electrical equipment 30 (such as the drive motor) plus the minimum voltage deviation (i.e., the first preset voltage value), then the current power supply of the supercapacitor 11 cannot support the discharge of the whole vehicle. At this time, the first switch 13, the second switch 14, and the fourth switch 16 are closed, and the third switch 15 is opened. The main BMS sends the first mode (also known as the "high voltage side constant voltage mode") to the bidirectional converter 12, and sets the voltage of the bidirectional converter 12 to the rated voltage of the drive motor. At this time, the battery 10 will charge the supercapacitor 11 at maximum power according to the voltage difference with the supercapacitor 11. At the same time, the battery 10 will also supply power to the external electrical equipment 30. Furthermore, when the vehicle is powered on, if the main BMS detects that the voltage of the supercapacitor 11 is less than the rated voltage minus the lower limit voltage deviation of the external electrical equipment 30, it directly enters the second mode (also known as the "supercapacitor 11 power supply mode"), closes the second switch 14, the third switch 15, and the fourth switch 16, and opens the first switch 13. The main BMS sends the first sub-mode of the second mode (also known as the "high-voltage side constant power P1 discharge mode") to the bidirectional converter 12. At this time, the battery 10 mainly acts as an energy source to charge the supercapacitor 11 at a power value of P1, and then the supercapacitor 11 supplies power to the external electrical equipment 30. If the voltage of the supercapacitor 11 is less than the rated voltage plus the upper limit voltage deviation of the external electrical equipment 30 during the driving process, then the second switch 14, the third switch 15, and the fourth switch 16 are closed, and the first switch 13 is opened. The main BMS sends the second sub-mode of the second mode (also known as the "high-voltage side constant power P2 discharge mode") to the bidirectional converter 12. The battery 10 charges the supercapacitor 11 at a power value of P2, and then the supercapacitor 11 supplies power to the external electrical equipment 30. If the voltage of supercapacitor 11 is greater than the rated voltage plus upper limit voltage deviation of external electrical equipment 30, then the second switch 14, the third switch 15, and the fourth switch 16 are closed, the first switch 13 is opened, the main BNS sends the third sub-mode of the second mode (also known as "DCDC idle mode") to the bidirectional converter 12, the battery 10 stops discharging and enters a static state, and the supercapacitor 11 supplies power to the external electrical equipment 30 alone.

[0077] In the voltage classification of supercapacitor 11, the order is: maximum voltage > rated voltage + upper limit voltage deviation > rated voltage > rated voltage - lower limit voltage deviation > minimum voltage + minimum voltage deviation > minimum voltage. The upper limit voltage deviation, lower limit voltage deviation, and minimum voltage deviation are voltage deviations. During discharge, the power of the bidirectional converter 12 is as follows: high-voltage side constant voltage mode (maximum power value) > high-voltage side constant power P1 discharge mode > high-voltage side constant power P2 discharge mode > DC-DC idle mode (e.g., 0kW). Here, P1 is the power value that continuously supplies power to the vehicle while maintaining a low to medium charge state in supercapacitor 11; P2 is the power value that continuously supplies power to the vehicle while maintaining a rated voltage range in supercapacitor 11, and its specific value depends on the actual drive motor power.

[0078] Figure 9 This is a schematic diagram showing the relationship between the battery power threshold of the battery 10 and the operating mode of the bidirectional converter 12 in an embodiment of this application.

[0079] To describe in detail the charging and discharging methods of steps S400 to S600, a specific charging process is provided: [Combined with...] Figure 9 When the main BMS detects the charging plug connection signal of the external charging device 20 (such as a charger), the secondary BMS (i.e., the second control device 182) is awakened, closing the first switch 13 and the second switch 14, and opening the third switch 15 (the external power device 30 can be understood as not connected during charging, so the fourth switch 16 and the fifth switch 17 can be ignored). The main BMS sends a third mode (also called "idle mode") to the bidirectional converter 12, and the external charging device 20 first charges the battery 10 separately. If the SOC value of the battery 10 is greater than the preset capacity (such as 50%) during the charging process, the main BMS sends a fourth mode (also called "DC-CDC high-voltage side constant current mode") to the bidirectional converter 12, setting the charging current (i.e., fixed current value) to 0.1C of the battery 10's capacity. At this time, the external charging device 20 charges the battery 10, and the battery 10 charges the supercapacitor 11 at 0.1C. After supercapacitor 11 is charged, the main BMS needs to detect whether the voltage of supercapacitor 11 is less than the rated voltage plus the upper limit voltage deviation (i.e., the second preset voltage value, which can also be written as "supercapacitor 11 upper limit voltage + upper limit voltage deviation"). If the upper limit voltage of supercapacitor 11 is reached, the main BMS sends a third mode to the bidirectional converter 12 to pause charging of supercapacitor 11, and the charging of supercapacitor 11 ends. If the upper limit voltage of supercapacitor 11 is not reached, the battery 10 continues to charge while the battery 10 charges supercapacitor 11. Then it is determined whether the battery 10 has reached the full charge condition. If the battery 10 is fully charged, the first switch 13 and the second switch 14 are disconnected, the charging of battery 10 ends, and the entire battery 10 system 100 is fully charged.

[0080] In other words, during the charging process, the energy storage source battery 10 primarily replenishes the battery. At this time, the main BMS controls the bidirectional converter 12 to enter various states based on the SOC state of the battery 10. When the SOC of the battery 10 is less than 50%, the bidirectional converter 12 is controlled to enter the idle mode, and the charger fully charges the battery 10. When the battery 10's SOC is greater than 50%, the bidirectional converter 12 is controlled to enter the DC-DC high-voltage side constant current mode, where the charger charges the battery 10 while the battery 10 replenishes the supercapacitor 11. Generally, the supercapacitor 11 has a relatively small capacity and can be fully charged relatively quickly compared to the battery 10. After it is fully charged, the bidirectional converter 12 returns to its original idle mode and continues charging the battery 10 until charging is complete.

[0081] Based on the above, this application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the charging and discharging control method of any of the above embodiments of this application.

[0082] Based on the above, this application also provides a vehicle including a charging and discharging system 100 of any of the above embodiments of this application. The charging and discharging system 100 includes a control device 18, which is used to execute the charging and discharging control method of any of the above embodiments of this application.

[0083] In this application, "multiple" refers to two or more. Unless otherwise expressly defined, the term "connection" should be interpreted broadly, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0084] The terms "first," "second," "third," "fourth," etc. (if present) in this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. The term "and / or" in this application is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Furthermore, the character " / " in this application generally indicates that the preceding and following related objects have an "or" relationship.

[0085] Unless otherwise specified, all steps in this application may be performed sequentially or randomly. For example, if the method includes steps A and B, it means that the method may include steps A and B performed sequentially, or it may include steps B and A performed sequentially. For example, if the method may also include step C, it means that step C may be added to the method in any order. For example, the method may include steps A, B, and C, or it may include steps A, C, and B, or it may include steps C, A, and B, etc.

[0086] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A charging and discharging system, characterized in that, The device includes a battery, a supercapacitor, and a bidirectional converter. The positive terminal of the battery is connected to the positive terminal of an external charging device and the low-voltage positive terminal of the bidirectional converter. The negative terminal of the battery is connected to the low-voltage negative terminal of the bidirectional converter. The positive terminal of the supercapacitor is connected to the high-voltage positive terminal of the bidirectional converter, and the connection point between the positive terminal of the supercapacitor and the high-voltage positive terminal of the bidirectional converter is connected to the positive terminal of the external electrical device. The negative terminal of the supercapacitor is connected to the high-voltage negative terminal of the bidirectional converter, and the connection point between the negative terminal of the supercapacitor and the high-voltage negative terminal of the bidirectional converter is connected to the negative terminal of the external electrical device. The high-voltage negative terminal of the bidirectional converter is also connected to the negative terminal of the external charging device.

2. The charging and discharging system according to claim 1, characterized in that, It also includes a control device, a first switch, a second switch, and a third switch. The first switch is located between the positive terminal of the battery and the positive terminal of the external charging device. The second switch is located between the positive terminal of the battery and the low-voltage side positive terminal of the bidirectional converter. The third switch is located between the connection point of the positive terminal of the supercapacitor and the high-voltage side positive terminal of the bidirectional converter and the positive terminal of the external electrical device.

3. The charging and discharging system according to claim 2, characterized in that, When the voltage of the supercapacitor is less than or equal to the first preset voltage value, the control device controls the first switch and the second switch to close and controls the third switch to open, and controls the bidirectional converter to operate in the first mode, so that the battery supplies power to the supercapacitor at maximum power. When the voltage of the supercapacitor is greater than the first preset voltage value, the control device controls the second switch and the third switch to close and controls the first switch to open, and controls the bidirectional converter to operate in the second mode, so that the battery supplies power to the supercapacitor with multiple preset power, and the supercapacitor supplies power to the external electrical equipment, wherein the preset power is less than the maximum power and the multiple preset power decreases sequentially, and the second mode corresponds to the multiple preset power being divided into multiple sub-modes.

4. The charging and discharging system according to claim 3, characterized in that, The control device controls the opening and closing of the first switch, the second switch, and the third switch, as well as the working mode of the bidirectional converter, based on the battery's power level, so that the battery can obtain and store electrical energy through the external charging device, and when the power level is greater than a preset power level, it supplies power to the supercapacitor through the bidirectional converter.

5. The charging and discharging system according to claim 4, characterized in that, When the battery charge is less than or equal to the preset battery charge, the control device controls the first switch and the second switch to close and controls the bidirectional converter to operate in the third mode, so that the battery can obtain and store electrical energy through the external charging device. When the battery charge is greater than the preset charge, the control device controls the first switch and the second switch to close and controls the bidirectional converter to operate in the fourth mode, so that the battery can obtain and store electrical energy through the external charging device, and supply power to the supercapacitor with a fixed current value through the bidirectional converter. When the charge is greater than the preset charge and the voltage of the supercapacitor is greater than or equal to the second preset voltage value, the control device controls the first switch and the second switch to close and controls the bidirectional converter to operate in the third mode, so that the battery can obtain and store electrical energy through the external charging device, and stops supplying power to the supercapacitor with a fixed current value through the bidirectional converter; wherein, the second preset voltage value is greater than the first preset voltage value.

6. The charging and discharging system according to claim 4, characterized in that, The positive terminal of the battery is also connected to the positive terminal of the external electrical device, and the first switch is disposed between the positive terminal of the battery and the positive terminal of the external electrical device; When the battery power is less than or equal to the preset battery power, the control device controls the first switch and the second switch to close and controls the third switch to open, and controls the bidirectional converter to operate in the third mode, so that the battery can obtain and store electrical energy through the external charging device. When the battery charge exceeds the preset charge level, the control device controls the first switch and the second switch to close and the third switch to open, and controls the bidirectional converter to operate in the fourth mode, so that the battery can obtain and store electrical energy through the external charging device, and supply power to the supercapacitor with a fixed current value through the bidirectional converter. When the charge is greater than the preset charge and the voltage of the supercapacitor is greater than or equal to the second preset voltage value, the control device controls the first switch and the second switch to close and controls the third switch to open, and controls the bidirectional converter to operate in the third mode, so that the battery can obtain and store electrical energy through the external charging device, and stops supplying power to the supercapacitor through the bidirectional converter at a fixed current value; wherein, the second preset voltage value is greater than the first preset voltage value.

7. A charging and discharging control method, characterized in that, The control method, applied in any one of claims 1 to 6, comprises: The voltage value of the supercapacitor is obtained, and the opening and closing of multiple switches and the working mode of the bidirectional converter are controlled based on the voltage value of the supercapacitor, so that the supercapacitor can receive power from the battery through the bidirectional converter and provide power to external electrical equipment. The battery's charge level is obtained, and multiple switches are opened and closed based on the battery's charge level, as well as the working mode of the bidirectional converter, so that the battery can obtain and store electrical energy through an external charging device, and when the charge level is greater than a preset charge level, the bidirectional converter supplies power to the supercapacitor.

8. The charging and discharging control method according to claim 7, characterized in that, The method of controlling the opening and closing of multiple switches and the operating mode of the bidirectional converter based on the voltage value of the supercapacitor, so that the supercapacitor receives power from the battery through the bidirectional converter and provides electrical energy to external electrical equipment, includes: When the voltage of the supercapacitor is less than or equal to the first preset voltage value, the first switch and the second switch are closed and the third switch is opened, and the working mode of the bidirectional converter is controlled to the first mode so that the battery supplies power to the supercapacitor at the maximum power. When the voltage of the supercapacitor is greater than the first preset voltage value, the second switch and the third switch are controlled to close and the first switch is controlled to open. The bidirectional converter is also controlled to operate in the second mode, so that the battery supplies power to the supercapacitor at multiple preset power levels and the supercapacitor supplies power to the external electrical equipment. Wherein, the preset power is less than the maximum power and the multiple preset powers decrease sequentially, and the second mode is divided into multiple sub-modes corresponding to the multiple preset powers.

9. The charging and discharging control method according to claim 8, characterized in that, The method of controlling the opening and closing of multiple switches and the operating mode of the bidirectional converter based on the battery's power level, so as to enable the battery to obtain and store electrical energy through an external charging device, and to supply power to the supercapacitor through the bidirectional converter when the battery power level is greater than a preset level, includes: When the battery power is less than or equal to the preset battery power, the first switch and the second switch are closed and the bidirectional converter is controlled to operate in the third mode, so that the battery can obtain and store electrical energy through the external charging device. When the battery charge is greater than the preset charge, the first switch and the second switch are closed and the bidirectional converter is controlled to operate in the fourth mode, so that the battery can obtain and store electrical energy through the external charging device and supply power to the supercapacitor with a fixed current value through the bidirectional converter. When the battery charge is greater than the preset charge and the voltage of the supercapacitor is greater than or equal to the second preset voltage value, the first switch and the second switch are closed, and the working mode of the bidirectional converter is controlled to the third mode, so that the battery can obtain and store electrical energy through the external charging device, and the power supply to the supercapacitor through the bidirectional converter at a fixed current value is stopped. Wherein, the second preset voltage value is greater than the first preset voltage value.

10. The charging and discharging control method according to claim 8, characterized in that, The method of controlling the opening and closing of multiple switches and the operating mode of the bidirectional converter based on the battery's power level, so as to enable the battery to obtain and store electrical energy through an external charging device, and to supply power to the supercapacitor through the bidirectional converter when the battery power level is greater than a preset level, includes: When the battery power is less than or equal to the preset battery power, the first switch and the second switch are closed and the third switch is opened, and the bidirectional converter is controlled to operate in the third mode, so that the battery can obtain and store electrical energy through the external charging device. When the battery charge is greater than the preset charge, the first switch and the second switch are closed and the third switch is opened. The bidirectional converter is also controlled to operate in the fourth mode so that the battery can obtain and store electrical energy through the external charging device and supply power to the supercapacitor with a fixed current value through the bidirectional converter. When the battery charge is greater than the preset charge and the voltage of the supercapacitor is greater than or equal to the second preset voltage value, the first switch and the second switch are controlled to close and the third switch is controlled to open. The working mode of the bidirectional converter is also controlled to the third mode, so that the battery can obtain and store electrical energy through the external charging device, and the power supply to the supercapacitor through the bidirectional converter at a fixed current value is stopped. Wherein, the second preset voltage value is greater than the first preset voltage value.

11. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the charge / discharge control method according to any one of claims 7 to 10.

12. A vehicle, characterized in that, The system includes a charge / discharge system as described in any one of claims 1 to 6, the charge / discharge system including a control device for performing the charge / discharge control method as described in any one of claims 7 to 10.

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