Vehicle control method

Abstract

The present invention discloses a vehicle control method, which relates to the field of vehicle technology. The vehicle control method comprises the following steps: monitoring the real-time temperature of an electric drive system; when the temperature of any one of the motor, motor controller and battery in the electric drive system is greater than the first set temperature corresponding thereto, turning on the thermal management control system, and gradually increasing the heat dissipation capacity of the thermal management control system as the temperature of the electric drive system increases. When the temperature of any one of the motor, motor controller and battery in the electric drive system is greater than the second set temperature corresponding thereto, while increasing the heat dissipation capacity of the thermal management control system, the driving power or driving power change rate of the electric drive system is limited while ensuring that the total power demanded by the vehicle remains unchanged; as the temperature of the electric drive system increases, the braking power provided by the electric drive system is further limited, so as to achieve rapid cooling of the electric drive system and ensure the economy and comfort of the vehicle.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular to a vehicle control method. Background Art

[0002] Both hybrid vehicles and pure electric vehicles include electric drive systems, which include motors, motor controllers and batteries. Hybrid vehicles also include engine systems. When the vehicle is under high load, the temperature of the electric drive system and engine system will be too high, which will affect the vehicle's economy and driving comfort.

[0003] At present, both hybrid vehicles and pure electric vehicles are equipped with thermal management control systems, which perform thermal management on the electric drive system and engine system. However, since the vehicle's thermal management control system and vehicle controller are developed by different manufacturers, there is important information interaction between signals, but the interactive information only shows whether the current status of the components in the electric drive system is normal or malfunctioning, and cannot effectively prevent the electric drive system's components from malfunctioning due to overheating caused by the electric drive system's temperature rising too fast and the vehicle's thermal management control system's failure to dissipate heat in time, which reduces the service life of the components in the electric drive system and affects the vehicle's economy and driving comfort. Summary of the invention

[0004] The object of the present invention is to provide a vehicle control method to achieve rapid cooling of an electric drive system, thereby increasing the service life of components of the electric drive system and ensuring the economy and driving comfort of the vehicle.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A vehicle control method, wherein the vehicle includes an electric drive system and a thermal management control system, wherein the electric drive system includes a motor, a motor controller and a battery, and the thermal management control system can dissipate heat for the electric drive system; wherein the vehicle control method includes the following steps:

[0007] Monitoring the real-time temperature of the electric drive system;

[0008] When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a first set temperature corresponding thereto, the thermal management control system is turned on, and the heat dissipation capacity of the thermal management control system is gradually increased as the temperature of the electric drive system increases;

[0009] When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the second set temperature corresponding thereto, the heat dissipation capacity of the thermal management control system is increased, and while ensuring that the total power required by the vehicle remains unchanged, the driving power or the driving power change rate of the electric drive system begins to be limited; as the temperature of the electric drive system increases, the thermal management control system is controlled to dissipate heat at maximum capacity, and the limit amount of the driving power or the driving power change rate of the electric drive system is gradually increased, while limiting the braking power provided by the electric drive system;

[0010] Among them, the first set temperature corresponding to each of the motor, the motor controller and the battery in the electric drive system is lower than the second set temperature corresponding to each of the motor, the motor controller and the battery.

[0011] As an optional solution of the vehicle control method, the thermal management control system includes a cooling water pump, a radiator and a cooling fan group, the cooling water pump and the radiator are both arranged in the cooling circuit of the electric drive system, and the cooling fan group dissipates heat for the radiator; when the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the first set temperature corresponding thereto, the thermal management control system is turned on, and the specific steps of gradually increasing the heat dissipation capacity of the thermal management control system as the temperature in the electric drive system increases include:

[0012] When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a first set temperature corresponding thereto, the cooling water pump and the cooling fan group are turned on, the cooling water pump operates at a first speed, and the cooling fan group operates at a first heat dissipation power;

[0013] When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a third set temperature corresponding thereto, the cooling water pump operates at a second speed, the second speed is greater than the first speed, and the cooling fan group operates at a second heat dissipation power, the second heat dissipation power is greater than the first heat dissipation power;

[0014] Among them, the third set temperature corresponding to each of the motor, the motor controller and the battery in the electric drive system is greater than the first set temperature corresponding to each of the motor, the motor controller and the battery, and is less than the second set temperature corresponding to each of the motor, the motor controller and the battery.

[0015] As an optional solution of the vehicle control method, when the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the corresponding second set temperature, while increasing the heat dissipation capacity of the thermal management control system, while ensuring that the total power required by the vehicle remains unchanged, the driving power or the driving power change rate of the electric drive system begins to be limited; and as the temperature of the electric drive system increases, the thermal management control system is controlled to dissipate heat at maximum capacity, and the driving power or the driving power change rate of the electric drive system is gradually increased. The specific steps of limiting the braking power provided by the electric drive system include:

[0016] When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the corresponding second set temperature, the heat dissipation capacity of the thermal management control system is increased, and the driving power or the driving power change rate of the electric drive system is limited while ensuring that the total power required by the vehicle remains unchanged;

[0017] When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a fourth set temperature corresponding thereto, the thermal management control system is controlled to dissipate heat at maximum capacity, and the limit amount of the driving power or the driving power change rate of the electric drive system is gradually increased, while limiting the braking power provided by the electric drive system;

[0018] Among them, the second set temperature corresponding to each of the motor, the motor controller and the battery in the electric drive system is lower than the fourth set temperature corresponding to each of the motor, the motor controller and the battery.

[0019] As an optional scheme for the vehicle control method, the thermal management control system also includes an air conditioner, which dissipates heat for the battery through a refrigeration circuit; when the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the corresponding second set temperature, the method of increasing the heat dissipation capacity of the thermal management control system includes: turning on the air conditioner to cool the battery through the air conditioner.

[0020] As an optional solution of the vehicle control method, the specific steps of turning on the air conditioner and cooling the battery by the air conditioner include:

[0021] When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a second set temperature corresponding thereto, controlling the compressor of the air conditioner to operate at a third speed;

[0022] When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a fourth set temperature corresponding thereto, controlling the compressor of the air conditioner to operate at a fourth speed, the fourth speed being greater than the third speed;

[0023] Among them, the second set temperature corresponding to each of the motor, the motor controller and the battery in the electric drive system is lower than the fourth set temperature corresponding to each of the motor, the motor controller and the battery.

[0024] As an optional solution of the vehicle control method, the vehicle is a hybrid vehicle, the hybrid vehicle includes an engine system and the electric drive system, the engine system and the electric drive system jointly drive the vehicle in a hybrid drive mode; while ensuring that the total power required by the vehicle remains unchanged, the method for starting to limit the driving power of the electric drive system includes the following steps:

[0025] Controlling the vehicle to drive in a hybrid driving mode;

[0026] According to the real-time temperature of the electric drive system and the real-time speed of the vehicle, the driving power of the electric drive system is reduced and the output power of the engine system is increased, and the increase in the output power of the engine system is the decrease in the driving power of the electric drive system. The increased output power of the engine system is the first output power of the engine system.

[0027] As an optional scheme for the control method of the vehicle, the first output power of the engine system = the total power required by the vehicle - the required power of the electric drive system × the first driving coefficient, wherein the first driving coefficient is obtained by querying a correspondence table between the driving coefficient of the electric drive system driving power and the real-time temperature of the electric drive system and the real-time speed of the vehicle.

[0028] As an optional solution of the vehicle control method, a method of gradually increasing the limit amount of the driving power of the electric drive system as the temperature of the electric drive system increases after the driving power of the electric drive system is limited while ensuring that the total power demand of the vehicle remains unchanged includes:

[0029] According to the real-time temperature of the electric drive system and the real-time speed of the vehicle, the driving power of the electric drive system continues to be reduced, and the further reduction amount of the driving power of the electric drive system is increased to the first output power of the engine system. The output power of the engine system after the first output power is increased is the second output power of the engine system.

[0030] As an optional scheme for the control method of the vehicle, the second output power of the engine system = the total power required by the vehicle - the required power of the electric drive system × the second driving coefficient, wherein the second driving coefficient is obtained by querying the correspondence table between the driving coefficient of the driving power of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle, and the second driving coefficient is less than the first driving coefficient.

[0031] As an optional solution of the vehicle control method, the vehicle is a pure electric vehicle, and the method of starting to limit the driving power of the electric drive system while ensuring that the total power required by the vehicle remains unchanged includes the following steps:

[0032] According to the real-time temperature of the electric drive system and the real-time target speed of the vehicle, the torque change rate of the motor is reduced to reduce the charge and discharge power change rate of the battery. At this time, the total power demand of the vehicle and the maximum speed of the vehicle remain unchanged, the dynamic switching frequency of the electric drive system is reduced, and the torque change rate of the motor after reduction is the first torque change rate of the motor.

[0033] As an optional scheme for the control method of the vehicle, the first torque change rate of the motor = the current torque change rate of the motor × the first torque change rate coefficient, wherein the first torque change rate coefficient is obtained by querying the correspondence table between the torque change rate of the motor and the real-time temperature of the electric drive system and the real-time target speed of the vehicle.

[0034] As an optional solution of the vehicle control method, a method of gradually increasing the limit amount of the driving power of the electric drive system as the temperature of the electric drive system increases after the driving power of the electric drive system is limited while ensuring that the total power demand of the vehicle remains unchanged includes:

[0035] According to the real-time temperature of the electric drive system and the real-time speed of the vehicle, the torque change rate of the motor continues to be reduced to continue to reduce the charge and discharge power change rate of the battery. The dynamic switching frequency of the electric drive system continues to decrease, and the torque change rate of the motor after the first torque change rate is reduced is the second torque change rate of the motor.

[0036] As an optional scheme for the control method of the vehicle, the second torque change rate of the motor = the current torque change rate of the motor × the second torque change rate coefficient, wherein the second torque change rate coefficient is obtained by querying the correspondence table between the torque change rate of the motor and the real-time temperature of the electric drive system and the real-time target speed of the vehicle, and the second torque change rate coefficient is smaller than the first torque change rate coefficient.

[0037] As an optional scheme for the control method of the vehicle, when the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the corresponding second set temperature, the heat dissipation capacity of the thermal management control system is increased, and while ensuring that the total power demand of the vehicle remains unchanged, the driving power or the driving power change rate of the electric drive system begins to be limited; as the temperature of the electric drive system increases, the thermal management control system is controlled to dissipate heat at maximum capacity, and the limit on the driving power or the driving power change rate of the electric drive system is gradually increased, while limiting the braking power provided by the electric drive system, and limiting the required power of the electric drive system according to the real-time temperature of the electric drive system and the real-time speed of the vehicle. The required power of the electric drive system after limitation is the first required power of the electric drive system.

[0038] As an optional scheme for the control method of the vehicle, the first required power driven by the electric drive system = the required power driven by the electric drive system × the first driving power limiting coefficient, wherein the first driving power limiting coefficient is obtained by querying a correspondence table between the driving power limiting coefficient of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle.

[0039] As an optional solution of the vehicle control method, the braking system of the vehicle includes the electric drive system brake and a mechanical brake structure, and the method of limiting the braking power provided by the electric drive system includes:

[0040] The braking power provided by the electric drive system is reduced according to the real-time temperature of the electric drive system and the real-time speed of the vehicle. After the reduction, the required power for braking of the electric drive system is the first required power for braking of the electric drive system. The reduced braking power of the electric drive system is provided by the mechanical braking structure.

[0041] As an optional scheme for the control method of the vehicle, the first required power for braking the electric drive system = the required power for braking the electric drive system × the first braking power limiting coefficient, wherein the first braking power limiting coefficient is obtained by querying a correspondence table between the braking power limiting coefficient of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle.

[0042] Beneficial effects of the present invention:

[0043] The vehicle control method provided by the present invention monitors the real-time temperature of the motor, motor controller and battery in the electric drive system. When the temperature of any one of the motor, motor controller and battery is greater than the first set temperature corresponding thereto, the thermal management control system is turned on, and the heat dissipation capacity of the thermal management control system is gradually increased as the temperature of the electric drive system rises, so that when the temperature of any component in the electric drive system rises, the heat can be quickly dissipated through the thermal management control system. If the temperature of the electric drive system continues to rise, when the temperature of any one of the motor, motor controller and battery is greater than the second set temperature corresponding thereto, while increasing the heat dissipation capacity of the thermal management control system, while ensuring that the total power required by the vehicle remains unchanged, the driving power or driving power change rate of the electric drive system is limited, that is, while dissipating the heat of the electric drive system, the speed of the temperature increase of the electric drive system is reduced to avoid the temperature of the electric drive system from rising too fast. If the temperature of the electric drive system continues to rise, the thermal management control system is controlled to dissipate heat at the maximum capacity, and the driving power or the limit amount of the driving power of the electric drive system is gradually increased, while limiting the braking power provided by the electric drive system. While cooling the electric drive system and reducing the rate of temperature rise of the electric drive system, the electric drive system's energy recovery power is reduced by limiting the electric drive system's braking power, that is, the electric drive system is cooled quickly at the expense of the vehicle's economy, thereby ensuring the service life of the electric drive system's components. When cooling the electric drive system, the vehicle control method coordinates the thermal management control system, the electric drive system, and the braking system to achieve rapid cooling of the electric drive system before the electric drive system's components fail due to heat, while ensuring that the vehicle can maximize its advantages and achieve the vehicle's economy and comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic diagram of a transmission system of a hybrid vehicle provided by an embodiment of the present invention;

[0045] Figure 2 is a schematic diagram of a thermal management control system for a hybrid vehicle provided by an embodiment of the present invention;

[0046] Figure 3 is a schematic diagram of a transmission system of a pure electric vehicle provided by an embodiment of the present invention;

[0047] Figure 4 is a schematic diagram of a thermal management control system for a pure electric vehicle provided by an embodiment of the present invention;

[0048] Figure 5 is a flow chart of a vehicle control method provided by an embodiment of the present invention;

[0049] Figure 6 is a flow chart of a method for controlling a vehicle thermal management control system provided by an embodiment of the present invention;

[0050] Figure 7 It is a flow chart of a method for controlling an electric drive system and a braking system of a vehicle provided in an embodiment of the present invention.

[0051] In the figure:

[0052] 1. Engine; 2. Clutch; 3. Motor; 4. Gearbox; 5. ECU; 6. MCU; 7. TCU / CCU; 8. Electric power steering pump; 9. Auxiliary machine controller; 10. Battery; 11. Instrument; 12. Shift handle; 13. CAN; 14. HCU; 15. Battery water pump; 16. Battery heat exchanger; 17. Motor water pump; 18. Motor controller; 19. First radiator; 20. Second radiator; 21. Third radiator; 22. First cooling fan group; 23. Second cooling fan group; 24. Engine heat exchanger; 25. Condenser; 26. Compressor; 27. Cab refrigeration circuit; 28. Cab heating circuit; 29. ​​Cab stop valve; 30. Cab warm water valve; 31. Battery warm water valve; 32. Normally closed two-position single-way valve; 33. Battery stop valve; 34. Engine thermostat; 35. VCU; 36. PTC. DETAILED DESCRIPTION

[0053] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0054] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0055] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection or a detachable 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 the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] Unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first feature being in direct contact with the second feature, or may include the first feature being in contact with the second feature through another feature between them instead of being in direct contact. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0057] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0058] At present, more and more vehicles are driven by electric drive systems. On the one hand, it saves energy and prevents environmental pollution; on the other hand, the vehicle is more economical; on the other hand, the starting comfort of vehicles driven by electric drive systems is better. However, the temperature of the motor, motor controller and battery in the electric drive system rises after long-term operation. The motor, motor controller and battery will fail due to high temperature, which reduces the service life of the components of the electric drive system and affects the economy and comfort of the vehicle.

[0059] Although the vehicle in the prior art dissipates heat from the electric drive system by setting up a thermal management control system, the thermal management control system includes a cooling water pump, a radiator, a cooling fan group and an air conditioner. The cooling water pump and the radiator are both set in the cooling circuit of the electric drive system. The cooling fan group dissipates heat for the radiator, and the air conditioner dissipates heat for the battery through the refrigeration circuit. However, since the vehicle's thermal management control system and the vehicle controller are developed by different manufacturers, there is important information interaction between the signals, but the interactive information only shows whether the current status of the components in the electric drive system is normal or faulty, and cannot effectively prevent the electric drive system from overheating and causing the components in the electric drive system to fail to dissipate heat in time due to the rapid temperature rise of the electric drive system, which reduces the service life of the components of the electric drive system and affects the economy and driving comfort of the vehicle.

[0060] Both hybrid vehicles and pure electric vehicles have electric drive systems, such as Figure 1As shown, the hybrid vehicle also includes an engine system, the engine system includes an engine 1, the electric drive system includes a motor 3 and a battery 10, and the battery 10 is a power battery with a BMS (Battery Management System). The battery 10 provides electrical energy for the motor 3, and the engine system can provide negative torque for the motor 3 to charge the battery 10. The engine 1 is connected to the ECU5 (Electronic Control Unit) through a low-voltage wiring harness, and the ECU5 is used to control the engine 1. The engine 1 is connected to the input shaft of the gearbox 4 through the clutch 2, and the output shaft of the gearbox 4 is connected to the drive shaft of the vehicle, and the drive shaft of the vehicle is used to drive the wheels to move. The clutch 2 is connected to the CCU (Clutch Control Unit) in the TCU / CCU7 through a low-voltage wiring harness, and the CCU is connected to the CAN13 (Controller Area Network). The CCU mainly controls the speed and target position of the clutch 2 to be separated and engaged, and is achieved by controlling the intake and exhaust solenoid valves of the clutch 2. The gearbox 4 is connected to the TCU (Transmission Control Unit) in the TCU / CCU7 through a low-voltage wiring harness, the TCU is connected to CAN13, the ECU5, the instrument 11 and the shift handle 12 are all connected to CAN13, and the CAN13 is connected to the HCU14 (Hybrid Control Unit, the main controller of the hybrid system). The motor 3 is mechanically connected to the gearbox 4, the battery 10 is connected to the MCU6 (Micro Control Unit, micro control unit) through a high-voltage wiring harness, the MCU6 is connected to the motor 3 through a high-voltage wiring harness, and the MCU6 controls the battery 10 to charge and discharge the motor 3. The battery 10 is connected to the auxiliary machine controller 9 through a high-voltage wiring harness, the auxiliary machine controller 9 is connected to the electric power steering pump 8 through a high-voltage wiring harness, and is connected to the battery through a low-voltage wiring harness.

[0061] The driving modes of hybrid vehicles include pure electric driving mode, engine driving mode and hybrid driving mode. Among them, driving the vehicle solely by the electric drive system is called pure electric driving mode, driving the vehicle solely by the engine system is called engine driving mode, and driving the vehicle together by the electric drive system and the engine system is called hybrid driving mode.

[0062] like Figure 2As shown, the current thermal management control system of hybrid vehicles is an integrated thermal management control system, which integrates the thermal management of the engine 1, the thermal management of the motor 3 and the motor controller 18, the thermal management of the battery 10, and the thermal management of the cab into a set of thermal management control systems through a control valve group. The integrated thermal management control system includes a cooling circuit, a heating circuit, a motor circuit, and a battery circuit. A condenser 25 and a compressor 26 are provided in the cooling circuit. The condenser 25 is connected to the cab refrigeration circuit 27 through a cab stop valve 29, and is connected to the battery refrigeration circuit through a battery stop valve 33 to cool the battery 10. The refrigerant flowing through the cab refrigeration circuit 27 and the battery refrigeration circuit is returned to the condenser 25 through the normally closed two-position one-way valve 32 and the compressor 26. When there is a cooling demand in the cab, the refrigerant passes through the cab refrigeration circuit 27 first. The engine heat exchanger 24 is connected between the normally closed two-position one-way valve 32 and the compressor 26. The engine heat exchanger 24 is connected to the engine 1. When the engine 1 has a cooling demand, the normally closed two-position one-way valve 32 is opened, so that the refrigerant after passing through the cab and the battery 10 passes through the engine heat exchanger 24 and then through the compressor 26 to return to the condenser 25. A first radiator 19 is provided in the heating circuit. The internal circulation water pipe of the engine 1 is connected to the first radiator 19 through the engine thermostat 34. The flow rate of the internal circulation water pipe of the engine 1 is controlled by the engine thermostat 34. The first radiator 19 is used to dissipate heat for the engine 1. The internal circulation water of the engine is connected to the cab heating circuit 28 through the cab warm water valve 30 to provide heat for the cab. The internal circulation water of the engine is connected to the battery heat exchanger 16 through the battery warm water valve 31 to heat the battery 10. Finally, the water passing through the cab heating circuit 28 and the battery heat exchanger 16 returns to the internal circulation water pipe of the engine 1. The motor circuit is provided with a motor 3, a motor controller 18, a motor water pump 17 and a second radiator 20. The motor water pump 17 provides power for the circulating water in the motor circuit, and the second radiator 20 is used to dissipate heat for the motor 3 and the motor controller 18. The battery circuit is provided with a battery 10, a battery water pump 15, a battery heat exchanger 16 and a third radiator 21. The battery water pump 15 provides power for the circulating water in the battery circuit, the battery heat exchanger 16 performs heat exchange with the heat in the cooling circuit and the heating circuit, thereby cooling or heating the battery 10, and the third radiator 21 is used to dissipate heat for the battery 10. The first radiator 19, the second radiator 20 and the third radiator 21 share a cooling fan group, and the cooling fan group includes a first cooling fan group 22 and a second cooling fan group 23. According to the heat dissipation requirements of the vehicle, one of the first cooling fan group 22 and the second cooling fan group 23 can be controlled to work, or both cooling fan groups can be controlled to work at the same time. The cooling fan group can be driven by the engine 1 or by the motor 3.

[0063] The thermal management control system of the hybrid vehicle is also electrically connected to the HCU14 via CAN13, and the start and stop, speed and power of each component in the thermal management control system of the hybrid vehicle are controlled by the HCU14.

[0064] like Figure 3 As shown, the difference between the transmission system of a pure electric vehicle and a hybrid vehicle is that there is no engine 1, clutch 2 and ECU5 for controlling the engine 1. CAN13 is connected to VCU35 (Vehicle control unit). The driving power of a pure electric vehicle can only be provided by the electric drive system. In order to ensure the safety of the vehicle and prevent the vehicle from being unable to brake effectively due to a failure of the electric drive system. Both hybrid vehicles and pure electric vehicles are provided with a mechanical braking structure, that is, the braking of hybrid vehicles and pure electric vehicles can be achieved through the electric drive system braking and / or the mechanical braking structure braking.

[0065] like Figure 4 As shown, the difference between the thermal management control system of a pure electric vehicle and that of a hybrid vehicle is that there is no heating circuit of the engine system, and the cab heating circuit 28 and the battery heat exchanger 16 both provide heat through a separately provided PTC36 (Positive Temperature Coefficient). The thermal management control system of a pure electric vehicle is also electrically connected to the VCU35 through the CAN13, and the VCU35 controls the start and stop, speed and power of each component in the thermal management control system of the pure electric vehicle.

[0066] The present invention provides a vehicle control method, which achieves rapid cooling of components of the electric drive system by collaboratively controlling a thermal management control system, an electric drive system and a vehicle's braking system, thereby increasing the service life of the components of the electric drive system while ensuring the economy and driving comfort of the vehicle.

[0067] like Figure 5 As shown, the vehicle control method provided in this embodiment includes the following steps:

[0068] S1. Monitor the real-time temperature of the electric drive system.

[0069] Specifically, the real-time temperatures of the motor 3, the motor controller 18 and the battery 10 in the electric drive system are monitored. The motor 3, the motor controller 18 and the battery 10 all have their own maximum temperatures that they can withstand, and the temperature rise rates of the motor 3, the motor controller 18 and the battery 10 are different. Therefore, in order to ensure that any component of the motor 3, the motor controller 18 and the battery 10 in the electric drive system will not fail due to heat, it is necessary to monitor the respective temperatures of the motor 3, the motor controller 18 and the battery 10 in the electric drive system in real time. When the temperature of any one of the motor 3, the motor controller 18 and the battery 10 is greater than the corresponding maximum temperature, in order to prevent the component from failing due to heat, cooling measures should be taken for the electric drive system to avoid excessive temperature rise of the component.

[0070] The temperatures of the motor 3 , the motor controller 18 and the battery 10 are all detected by the temperature sensors connected thereto respectively, and the three temperature sensors send their respective detected temperatures to the HCU 14 or the VCU 35 via the CAN 13 .

[0071] Since the temperature of the components in the electric drive system rises very quickly during the operation of the vehicle, and the maximum heat dissipation capacity of the thermal management control system is limited, if cooling measures are taken when the temperature of any one of the motor 3, the motor controller 18 and the battery 10 is greater than the corresponding maximum temperature, it is often too late and still cannot effectively prevent the various components in the electric drive system from malfunctioning due to overheating. In order to achieve effective control of the temperature of each component in the electric drive system, the control method provided in this embodiment begins to implement different cooling measures in stages before the temperature of any one of the motor 3, the motor controller 18 and the battery 10 reaches a temperature greater than the corresponding maximum temperature, and gradually increases the cooling capacity as the temperature of the electric drive system rises.

[0072] Exemplarily, the motor 3, the motor controller 18 and the battery 10 in the electric drive system all have a first set temperature, a second set temperature, a third set temperature and a fourth set temperature corresponding to each of them, wherein the first set temperature corresponding to each of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is less than the second set temperature corresponding to each of the motor 3, the motor controller 18 and the battery 10, and the third set temperature corresponding to each of the motor 3, the motor controller 18 and the battery 10 is greater than the first set temperature corresponding to each of the motor 3, the motor controller 18 and the battery 10, and is less than the second set temperature corresponding to each of the motor 3, the motor controller 18 and the battery 10. The second set temperature corresponding to each of the motor 3, the motor controller 18 and the battery 10 is less than the fourth set temperature corresponding to each of the motor 3, the motor controller 18 and the battery 10. For example: the first set temperature, the third set temperature, the second set temperature and the fourth set temperature of the motor 3 are set to 110°C, 115°C, 120°C and 125°C respectively; the first set temperature, the third set temperature, the second set temperature and the fourth set temperature of the motor controller 18 are set to 70°C, 75°C, 80°C and 85°C respectively; the first set temperature, the third set temperature, the second set temperature and the fourth set temperature of the battery 10 are set to 55°C, 58°C, 60°C and 62°C respectively.

[0073] S2. When any temperature of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the first set temperature corresponding thereto, the thermal management control system is turned on, and the heat dissipation capacity of the thermal management control system is gradually increased as the temperature of the electric drive system increases.

[0074] When it is monitored that the real-time temperature of the motor 3 in the electric drive system is 100°C, the real-time temperature of the motor controller 18 is 65°C, and the real-time temperature of the battery 10 is 56°C, it can be concluded that the real-time temperature of the battery 10, 56°C, is greater than the corresponding first set temperature of 55°C. At this time, the thermal management control system should be turned on to dissipate the heat of the electric drive system through the thermal management control system, and the heat dissipation capacity of the thermal management control system should be gradually increased as the temperature of the electric drive system increases.

[0075] Specifically, Figure 6 As shown, dissipating heat from the electric drive system through the thermal management control system and gradually increasing the heat dissipation capacity of the thermal management control system as the temperature of the electric drive system increases includes the following steps:

[0076] S201. When the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding first set temperature, the cooling water pump and the cooling fan group are turned on, the cooling water pump runs at a first speed, and the cooling fan group runs at a first heat dissipation power.

[0077] S202. When the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding third set temperature, the cooling water pump operates at a second speed that is greater than the first speed, and the cooling fan group operates at a second heat dissipation power that is greater than the first heat dissipation power.

[0078] Specifically, the thermal management control system includes two groups of cooling fan groups with the same power. When the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the first set temperature corresponding thereto, the cooling water pump operates at a first speed and only one group of cooling fan groups is turned on; when the temperature of the electric drive system continues to rise and the temperature of any one of the motor 3, the motor controller 18 and the battery 10 is greater than the third set temperature corresponding thereto, the cooling water pump operates at a second speed greater than the first speed, i.e., the water flow in the cooling circuit is increased to take away more heat for the electric drive system; and both groups of cooling fan groups are turned on at the same time to increase the heat dissipation power of the cooling fan groups, deliver more air volume to the electric drive system, and take away more heat.

[0079] It should be noted that the cooling water pump includes a motor water pump 17 and a battery water pump 15 , and the two cooling fan groups are respectively a first cooling fan group 22 and a second cooling fan group 23 .

[0080] That is, the thermal management control system compares the temperature of any one of the motor 3, the motor controller 18 and the battery 10 with its corresponding different set temperatures according to the temperature of the electric drive system, and controls the heat dissipation capacity of the thermal management control system at different temperature stages, which can not only achieve effective heat dissipation of the electric drive system, but also save energy and improve the economy of the vehicle.

[0081] S3. When the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding second set temperature, the heat dissipation capacity of the thermal management control system is increased, and while ensuring that the total power required by the vehicle remains unchanged, the driving power or the driving power change rate of the electric drive system begins to be limited; as the temperature of the electric drive system increases, the thermal management control system is controlled to dissipate heat at maximum capacity, and the driving power or the driving power change rate of the electric drive system is gradually increased. At the same time, the braking power provided by the electric drive system is limited.

[0082] Specifically, Figure 7 As shown, the following steps are included:

[0083] S301. When the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding second set temperature, the heat dissipation capacity of the thermal management control system is increased while the total power required by the vehicle is kept unchanged. The driving power or the driving power change rate of the electric drive system is limited.

[0084] When the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding second set temperature, the temperature of the components in the electric drive system is already very high. Since the temperature rise of the electric drive system is too fast, even if the thermal management control system continues to increase the heat dissipation capacity, the temperature of the electric drive system cannot be effectively controlled. At this time, the driving power of the electric drive system can be limited for hybrid vehicles while ensuring that the total power required by the vehicle remains unchanged, that is, the hybrid drive mode is turned on, the engine system is started, and part of the power originally borne by the electric drive system is transferred to the engine system to reduce the driving power of the electric drive system, thereby reducing the heat generated by the electric drive system. For pure electric vehicles, since the driving power of the electric drive system cannot be transferred, the driving power change rate of the electric drive system can be limited, that is, the torque change rate of the motor 3 in the electric drive system is reduced, thereby avoiding the temperature rise caused by the excessive torque change of the motor 3 and reducing the temperature rise rate of the electric drive system. In this way, without changing the maximum speed and total power required by the vehicle, the dynamic responsiveness of the vehicle is reduced, and the heat generated by the electric drive system is reduced by reducing the dynamic switching frequency of the electric drive system.

[0085] When the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding second set temperature, the method of increasing the heat dissipation capacity of the thermal management control system includes: turning on the air conditioner to cool the battery 10 through the air conditioner.

[0086] Specifically, when the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding second set temperature, the compressor 26 of the air conditioner is controlled to run at a third speed. Since the maximum temperature that the battery 10 can withstand is lower than that of the motor 3 and the motor controller 18, if the temperature of the battery 10 rises too quickly, it will fail due to heat faster than the motor 3 and the motor controller 18. Therefore, an air conditioner is set separately to cool the battery 10 to speed up the heat dissipation of the battery 10. When the battery 10 in the electric drive system reaches the corresponding second set temperature of 60°C earlier than the motor 3 and the motor controller 18, the air conditioner is turned on, and the speed of the compressor 26 is controlled to run at the third speed, that is, the compressor 26 is first controlled to run at a lower speed to cool the battery 10.

[0087] Of course, when the motor 3 in the electric drive system reaches its corresponding second set temperature, or the motor controller 18 reaches its corresponding second set temperature, the air conditioner is turned on to cool the battery 10, so that the cooling water pump and the cooling fan group can exchange more heat with the motor 3 or the motor controller 18, thereby achieving further heat dissipation of the motor 3 or the motor controller 18.

[0088] When the vehicle is a hybrid vehicle, while ensuring that the total power demand of the vehicle remains unchanged, the method for starting to limit the driving power of the electric drive system includes the following steps: controlling the vehicle to drive in a hybrid drive mode; reducing the driving power of the electric drive system and increasing the output power of the engine system according to the real-time temperature of the electric drive system and the real-time speed of the vehicle, and the increase in the output power of the engine system is the decrease in the driving power of the electric drive system, and the increased output power of the engine system is the first output power of the engine system.

[0089] Hybrid vehicles transfer part of the driving power originally borne by the electric drive system to the engine system, so that the engine system bears part of the driving power.

[0090] Specifically, the first output power of the engine system = the total power required by the vehicle - the required power of the electric drive system × the first driving coefficient, wherein the first driving coefficient is obtained by querying the correspondence table between the driving coefficient of the electric drive system driving power and the real-time temperature of the electric drive system and the real-time speed of the vehicle.

[0091] A corresponding table of the relationship between the driving coefficient of the electric drive system driving power and the real-time temperature of the electric drive system and the real-time speed of the vehicle can be obtained by those skilled in the art based on experiments. The first driving coefficient is greater than 0 and less than 1. When the real-time speed of the vehicle is constant, as the real-time temperature of the electric drive system increases, the driving coefficient of the electric drive system driving power decreases. That is, as the real-time temperature of the electric drive system increases, more driving power is transferred to the engine system.

[0092] The total power demanded by the vehicle is determined by the depth of the accelerator pedal depressed by the driver and the real-time speed of the vehicle, and the power demanded by the electric drive system is determined by the SOC (State of Charge) of the battery 10 and the real-time speed of the vehicle.

[0093] Similarly, for hybrid vehicles, in hybrid drive mode, when the temperature of the engine system rises rapidly, the engine system can also be cooled by reducing the driving power of the engine system and increasing the driving power of the electric drive system.

[0094] When the vehicle is a pure electric vehicle, the method for starting to limit the driving power of the electric drive system while ensuring that the total power required by the vehicle remains unchanged includes the following steps:

[0095] According to the real-time temperature of the electric drive system and the real-time target speed of the vehicle, the torque change rate of the motor 3 is reduced to reduce the charge and discharge power change rate of the battery 10. At this time, the total power demand of the vehicle and the maximum speed of the vehicle remain unchanged, the dynamic switching frequency of the electric drive system is reduced, and the torque change rate of the motor 3 after reduction is the first torque change rate of the motor 3.

[0096] Since pure electric vehicles are driven only by the electric drive system, while ensuring that the total power demand of the vehicle and the maximum speed of the vehicle remain unchanged, the rate of change of the charge and discharge power of the battery 10 can be reduced by reducing the rate of change of the torque of the motor 3, thereby making the driving power of the electric drive system change more slowly. For example, it originally takes 5 seconds for the speed of the vehicle to increase from 100km / hour to 120km / hour, but after reducing the rate of change of the torque of the motor 3, it may take 10 seconds. In this way, by reducing the frequency of dynamic switching of the electric drive system, although the dynamic responsiveness of the vehicle is reduced, the heat generated by the electric drive system is reduced, thereby preventing the temperature of the electric drive system from continuing to rise rapidly.

[0097] Specifically, the first torque change rate of motor 3 = the current torque change rate of motor 3 × the first torque change rate coefficient, wherein the first torque change rate coefficient is obtained by querying the correspondence table between the torque change rate of motor 3 and the real-time temperature of the electric drive system and the real-time target speed of the vehicle.

[0098] A corresponding table of the relationship between the torque change rate of the motor 3, the real-time temperature of the electric drive system, and the real-time target speed of the vehicle can be obtained by a person skilled in the art through experiments. The first torque change rate coefficient is greater than 0 and less than 1. When the real-time target speed of the vehicle remains unchanged, the higher the real-time temperature of the electric drive system, the smaller the first torque change rate coefficient, that is, the higher the real-time temperature of the electric drive system, the smaller the torque change rate of the motor 3.

[0099] The current torque change rate of the motor 3 can be obtained through the MCU 6.

[0100] S302. When the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding fourth set temperature, the thermal management control system is controlled to dissipate heat at maximum capacity, gradually increasing the driving power of the electric drive system or the limit of the driving power change rate, while limiting the braking power provided by the electric drive system.

[0101] Specifically, when the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding fourth set temperature, the compressor 26 of the air conditioner is controlled to run at a fourth speed, which is greater than the third speed. At this time, the speed of the cooling water pump has reached the second speed, the maximum speed, and both cooling fan groups have been turned on. The compressor 26 also runs at the fourth speed, the maximum speed, that is, the thermal management control system has achieved the maximum heat dissipation capacity.

[0102] For a hybrid vehicle, when the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding fourth set temperature, the method of gradually increasing the limit amount of the driving power of the electric drive system includes: according to the real-time temperature of the electric drive system and the real-time speed of the vehicle, continuing to reduce the driving power of the electric drive system, and increasing the further reduction amount of the driving power of the electric drive system to the first output power of the engine system, and the output power after the increase of the first output power of the engine system is the second output power of the engine system. That is, as the temperature of the electric drive system increases, more of the driving power originally borne by the electric drive system is transferred to the engine system.

[0103] Specifically, the second output power of the engine system = the total power required by the vehicle - the required power driven by the electric drive system × the second driving coefficient, wherein the second driving coefficient is obtained by querying the relationship between the driving coefficient of the electric drive system driving power and the real-time temperature of the electric drive system and the real-time speed of the vehicle, and the second driving coefficient is less than the first driving coefficient. That is, the driving power borne by the electric drive system is getting less and less, reducing the heat generated by the electric drive system, so that the temperature rise rate of the electric drive system decreases.

[0104] For a pure electric vehicle, when the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding fourth set temperature, the method of gradually increasing the limit amount of the driving power of the electric drive system includes: according to the real-time temperature of the electric drive system and the real-time speed of the vehicle, the torque change rate of the motor 3 is continuously reduced to continue to reduce the charge and discharge power change rate of the battery 10, the dynamic switching frequency of the electric drive system is continuously reduced, and the torque change rate of the motor 3 after the first torque change rate is reduced is the second torque change rate of the motor 3. That is, the heat generation of the electric drive system is reduced by continuing to reduce the change rate of the driving power of the electric drive system.

[0105] Specifically, the second torque change rate of the motor 3 = the current torque change rate of the motor 3 × the second torque change rate coefficient, wherein the second torque change rate coefficient is obtained by querying the relationship correspondence table between the torque change rate of the motor 3 and the real-time temperature of the electric drive system and the real-time target speed of the vehicle, and the second torque change rate coefficient is less than the first torque change rate coefficient. As the temperature of the electric drive system increases, the heat generated by the electric drive system is further reduced by further reducing the dynamic switching frequency of the electric drive system.

[0106] Since the braking systems of hybrid vehicles and pure electric vehicles both include electric drive system braking and mechanical braking structures, when limiting the braking power provided by the electric drive system, in order to ensure the safety of the vehicle, the braking power required by the vehicle must be kept unchanged. Therefore, the other part of the braking power is borne by the mechanical braking structure.

[0107] The method for limiting the braking power provided by the electric drive system includes: reducing the braking power provided by the electric drive system according to the real-time temperature of the electric drive system and the real-time speed of the vehicle, and after the reduction, the braking power provided by the electric drive system is the first required power for braking of the electric drive system, and the braking power reduced by the braking of the electric drive system is provided by a mechanical braking structure.

[0108] Specifically, the first required power of the electric drive system braking = the required power of the electric drive system braking × the first braking power limiting coefficient, wherein the first braking power limiting coefficient is obtained by querying the correspondence table between the limiting coefficient of the braking power of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle.

[0109] The required power of the electric drive system braking is determined by the depth of the driver's brake pedal and the vehicle's real-time speed.

[0110] Regarding the correspondence table of the relationship between the limiting coefficient of the braking power of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle, technical personnel in this field can obtain it through experiments. The first braking power limiting coefficient is greater than 0 and less than 1. When the real-time speed of the vehicle is constant, the higher the real-time temperature of the electric drive system, the smaller the limiting coefficient of the braking power of the electric drive system, that is, the less the braking power required by the electric drive system, and the more braking power borne by the mechanical braking structure.

[0111] Furthermore, for pure electric vehicles, when the temperature of any one of the motor 3, the motor controller 18 and the battery 10 in the electric drive system is greater than the corresponding fourth set temperature, the thermal management control system is controlled to dissipate heat at maximum capacity, gradually increasing the limit amount of the driving power of the electric drive system or the limit amount of the driving power change rate, while limiting the braking power provided by the electric drive system, and limiting the required power of the electric drive system according to the real-time temperature of the electric drive system and the real-time speed of the vehicle. The required power of the electric drive system after limitation is the first required power of the electric drive system.

[0112] Specifically, the first required power driven by the electric drive system = the required power driven by the electric drive system × the first driving power limiting coefficient, wherein the first driving power limiting coefficient is obtained by querying a correspondence table between the relationship between the limiting coefficient of the driving power of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle.

[0113] A corresponding table of the relationship between the limiting coefficient of the electric drive system driving power and the real-time temperature of the electric drive system and the real-time speed of the vehicle can be obtained by a person skilled in the art through experiments. The first driving power limiting coefficient is greater than 0 and less than 1. When the real-time speed of the vehicle is constant, the limiting coefficient of the driving power of the electric drive system decreases as the real-time temperature of the electric drive system increases. The required power of the electric drive system is determined by the SOC (State of Charge) of the battery 10 and the real-time speed of the vehicle.

[0114] For hybrid vehicles, the vehicle control method provided in this embodiment deeply coordinates and controls the thermal management control system, electric drive system, engine system and brake system of the vehicle. According to the temperature change of the electric drive system, the thermal management control system is first used to dissipate heat to varying degrees until the thermal management control system reaches the maximum heat dissipation capacity. When the temperature of the electric drive system rises to a relatively high level, part of the driving power originally borne by the electric drive system is transferred to the engine system, and as the temperature of the electric drive system continues to rise, the driving power borne by the electric drive system gradually decreases; at the same time, the braking power of the electric drive system is limited, and part of the braking power originally borne by the electric drive system is transferred to the mechanical brake structure of the vehicle, thereby reducing the power of the electric drive system, reducing the heat generated by various components in the electric drive system, and realizing rapid cooling of the electric drive system, which is more conducive to the long-term stable operation of the vehicle.

[0115] For pure electric vehicles, the vehicle control method provided in this embodiment coordinates the thermal management control system, the electric drive system and the braking system. According to the temperature change of the electric drive system, the thermal management control system is first used to dissipate heat to varying degrees until the thermal management control system reaches the maximum heat dissipation capacity. When the temperature of the electric drive system rises to a relatively high level, the torque change rate of the motor 3 is limited to reduce the dynamic responsiveness of the vehicle, and the heat generated by the electric drive system is reduced by reducing the dynamic switching frequency of the electric drive system. And as the temperature of the electric drive system rises, while increasing the limit amount of the torque change rate of the motor 3, the driving power and braking power of the electric drive system are limited to ensure that the electric drive system cools down quickly and returns to normal as soon as possible, reducing the failure rate of the components of the electric drive system while improving the economy and driving comfort of the vehicle.

[0116] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A method for controlling a vehicle, wherein the vehicle comprises an electric drive system and a thermal management control system, wherein the electric drive system comprises a motor, a motor controller and a battery, and the thermal management control system can dissipate heat for the electric drive system. It is characterized in that The vehicle control method comprises the following steps: Monitoring the real-time temperature of the electric drive system; When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a first set temperature corresponding thereto, the thermal management control system is turned on, and the heat dissipation capacity of the thermal management control system is gradually increased as the temperature of the electric drive system increases; When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the second set temperature corresponding thereto, the heat dissipation capacity of the thermal management control system is increased, and while ensuring that the total power required by the vehicle remains unchanged, the driving power or the driving power change rate of the electric drive system begins to be limited; as the temperature of the electric drive system increases, the thermal management control system is controlled to dissipate heat at maximum capacity, and the limit amount of the driving power or the driving power change rate of the electric drive system is gradually increased, while limiting the braking power provided by the electric drive system; Wherein, the first set temperature corresponding to each of the motor, the motor controller and the battery in the electric drive system is lower than the second set temperature corresponding to each of the motor, the motor controller and the battery; The vehicle is a pure electric vehicle. Under the condition that the total power required by the vehicle remains unchanged, the method for starting to limit the driving power of the electric drive system includes the following steps: According to the real-time temperature of the electric drive system and the real-time target speed of the vehicle, the torque change rate of the motor is reduced to reduce the charge and discharge power change rate of the battery. At this time, the total power demand of the vehicle and the maximum speed of the vehicle remain unchanged, and the dynamic switching frequency of the electric drive system is reduced.

2. The vehicle control method according to claim 1, It is characterized in that The thermal management control system includes a cooling water pump, a radiator and a cooling fan group, the cooling water pump and the radiator are both arranged in a cooling circuit of the electric drive system, and the cooling fan group dissipates heat for the radiator; when the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a first set temperature corresponding thereto, the thermal management control system is turned on, and the specific steps of gradually increasing the heat dissipation capacity of the thermal management control system as the temperature in the electric drive system increases include: When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a first set temperature corresponding thereto, the cooling water pump and the cooling fan group are turned on, the cooling water pump operates at a first speed, and the cooling fan group operates at a first heat dissipation power; When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a third set temperature corresponding thereto, the cooling water pump operates at a second speed, the second speed is greater than the first speed, and the cooling fan group operates at a second heat dissipation power, the second heat dissipation power is greater than the first heat dissipation power; Among them, the third set temperature corresponding to each of the motor, the motor controller and the battery in the electric drive system is greater than the first set temperature corresponding to each of the motor, the motor controller and the battery, and is less than the second set temperature corresponding to each of the motor, the motor controller and the battery.

3. The vehicle control method according to claim 1, It is characterized in that When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the corresponding second set temperature, while increasing the heat dissipation capacity of the thermal management control system, the driving power or the driving power change rate of the electric drive system is limited while ensuring that the total power required by the vehicle remains unchanged; and as the temperature of the electric drive system increases, the thermal management control system is controlled to dissipate heat at maximum capacity, and the driving power or the driving power change rate of the electric drive system is gradually increased. The specific steps of limiting the braking power provided by the electric drive system include: When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the corresponding second set temperature, the heat dissipation capacity of the thermal management control system is increased, and the driving power or the driving power change rate of the electric drive system is limited while ensuring that the total power required by the vehicle remains unchanged; When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a fourth set temperature corresponding thereto, the thermal management control system is controlled to dissipate heat at maximum capacity, and the limit amount of the driving power or the driving power change rate of the electric drive system is gradually increased, while limiting the braking power provided by the electric drive system; Among them, the second set temperature corresponding to each of the motor, the motor controller and the battery in the electric drive system is lower than the fourth set temperature corresponding to each of the motor, the motor controller and the battery.

4. The vehicle control method according to claim 1, It is characterized in that The thermal management control system also includes an air conditioner, which dissipates heat for the battery through a refrigeration circuit; when the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the corresponding second set temperature, the method for increasing the heat dissipation capacity of the thermal management control system includes: turning on the air conditioner to cool the battery through the air conditioner.

5. The vehicle control method according to claim 4, It is characterized in that The specific steps of turning on the air conditioner and cooling the battery by the air conditioner include: When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a second set temperature corresponding thereto, controlling the compressor of the air conditioner to operate at a third speed; When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than a fourth set temperature corresponding thereto, controlling the compressor of the air conditioner to operate at a fourth speed, the fourth speed being greater than the third speed; Among them, the second set temperature corresponding to each of the motor, the motor controller and the battery in the electric drive system is lower than the fourth set temperature corresponding to each of the motor, the motor controller and the battery.

6. The vehicle control method according to any one of claims 1 to 5, It is characterized in that The vehicle is a hybrid vehicle, and the hybrid vehicle includes an engine system and the electric drive system, and the engine system and the electric drive system jointly drive the vehicle in a hybrid drive mode; while ensuring that the total power required by the vehicle remains unchanged, the method for starting to limit the driving power of the electric drive system includes the following steps: controlling the vehicle to drive in a hybrid driving mode; According to the real-time temperature of the electric drive system and the real-time speed of the vehicle, the driving power of the electric drive system is reduced and the output power of the engine system is increased, and the increase in the output power of the engine system is the decrease in the driving power of the electric drive system. The increased output power of the engine system is the first output power of the engine system.

7. The vehicle control method according to claim 6, It is characterized in that The first output power of the engine system = the total power required by the vehicle - the required power driven by the electric drive system × the first driving coefficient, wherein the first driving coefficient is obtained by querying a correspondence table between the driving coefficient of the driving power of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle.

8. The vehicle control method according to claim 7, It is characterized in that Under the condition that the total power demanded by the vehicle remains unchanged, after starting to limit the driving power of the electric drive system, the method of gradually increasing the limiting amount of the driving power of the electric drive system as the temperature of the electric drive system increases includes: According to the real-time temperature of the electric drive system and the real-time speed of the vehicle, the driving power of the electric drive system continues to be reduced, and the further reduction amount of the driving power of the electric drive system is increased to the first output power of the engine system. The output power of the engine system after the first output power is increased is the second output power of the engine system.

9. The vehicle control method according to claim 8, It is characterized in that The second output power of the engine system = the total power required by the vehicle - the required power driven by the electric drive system × the second driving coefficient, wherein the second driving coefficient is obtained by querying the correspondence table between the driving coefficient of the driving power of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle, and the second driving coefficient is less than the first driving coefficient.

10. The vehicle control method according to any one of claims 1 to 5, It is characterized in that The reduced torque change rate of the motor is the first torque change rate of the motor.

11. The vehicle control method according to claim 10, It is characterized in that The first torque change rate of the motor=the current torque change rate of the motor×the first torque change rate coefficient, wherein the first torque change rate coefficient is obtained by querying a correspondence table of the relationship between the torque change rate of the motor and the real-time temperature of the electric drive system and the real-time target speed of the vehicle.

12. The vehicle control method according to claim 11, It is characterized in that Under the condition that the total power demanded by the vehicle remains unchanged, after starting to limit the driving power of the electric drive system, the method of gradually increasing the limiting amount of the driving power of the electric drive system as the temperature of the electric drive system increases includes: According to the real-time temperature of the electric drive system and the real-time speed of the vehicle, the torque change rate of the motor continues to be reduced to continue to reduce the charge and discharge power change rate of the battery. The dynamic switching frequency of the electric drive system continues to decrease, and the torque change rate of the motor after the first torque change rate is reduced is the second torque change rate of the motor.

13. The vehicle control method according to claim 12, It is characterized in that The second torque change rate of the motor = the current torque change rate of the motor × the second torque change rate coefficient, wherein the second torque change rate coefficient is obtained by querying the correspondence table between the torque change rate of the motor and the real-time temperature of the electric drive system and the real-time target speed of the vehicle, and the second torque change rate coefficient is less than the first torque change rate coefficient.

14. The vehicle control method according to claim 10, It is characterized in that When the temperature of any one of the motor, the motor controller and the battery in the electric drive system is greater than the corresponding second set temperature, the heat dissipation capacity of the thermal management control system is increased, and while ensuring that the total power demand of the vehicle remains unchanged, the driving power or the driving power change rate of the electric drive system begins to be limited; as the temperature of the electric drive system increases, the thermal management control system is controlled to dissipate heat at maximum capacity, and the limit amount of the driving power or the driving power change rate of the electric drive system is gradually increased, while limiting the braking power provided by the electric drive system, and limiting the required power of the electric drive system according to the real-time temperature of the electric drive system and the real-time speed of the vehicle. The required power of the electric drive system after limitation is the first required power of the electric drive system.

15. The vehicle control method according to claim 14, It is characterized in that The first required power driven by the electric drive system = the required power driven by the electric drive system × the first driving power limit coefficient, wherein the first driving power limit coefficient is obtained by querying the correspondence table between the driving power limit coefficient of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle.

16. The vehicle control method according to any one of claims 1 to 5, It is characterized in that The braking system of the vehicle includes the electric drive system brake and a mechanical brake structure, and the method for limiting the braking power provided by the electric drive system includes: The braking power provided by the electric drive system is reduced according to the real-time temperature of the electric drive system and the real-time speed of the vehicle. After the reduction, the required power for braking of the electric drive system is the first required power for braking of the electric drive system. The reduced braking power of the electric drive system is provided by the mechanical braking structure.

17. The vehicle control method according to claim 16, It is characterized in that The first required power for braking the electric drive system = the required power for braking the electric drive system × the first braking power limiting coefficient, wherein the first braking power limiting coefficient is obtained by querying a correspondence table between the braking power limiting coefficient of the electric drive system and the real-time temperature of the electric drive system and the real-time speed of the vehicle.

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