A control device for electric vehicle power system and related equipment

Abstract

The present application provides a control device for an electric vehicle power system and related equipment thereof, wherein the control device obtains the driving mode of the electric vehicle, the operating parameters of the electric vehicle, and the operating parameters of the power system, and responds to the throttle signal or brake signal of the electric vehicle, and outputs the torque distribution ratio of the front drive motor and the rear drive motor according to the driving mode of the electric vehicle, the operating parameters of the electric vehicle, and the operating parameters of the power system. By implementing the present application, the motor can be flexibly controlled by considering the influence of multiple factors, and the reliability is good.

Description

Technical Field

[0001] The present application relates to the field of new energy vehicles, and in particular to a control device for an electric vehicle power system and related equipment. Background Art

[0002] At present, during the operation of the vehicle, the torque distribution is mainly determined by the throttle signal and the brake signal. For example, the vehicle controller in the electric vehicle calculates the required torque of the vehicle according to the opening and closing degree of the throttle device and the opening and closing degree of the brake device, and controls the rotation of the motor with the required torque as the target, so that the motor can output the required torque to drive the wheels. It can be seen that the motor control in the prior art mainly considers the throttle and the brake, and the factors considered are single, resulting in insufficient flexibility of the motor control. Summary of the invention

[0003] The present application provides a control device for an electric vehicle power system and related equipment thereof, which flexibly controls the motor by considering the influence of multiple factors and has good reliability.

[0004] In the first aspect, an embodiment of the present application provides a control device for an electric vehicle power system, wherein the electric vehicle is provided with a plurality of driving modes that can be switched. The power system and the control device are located in the electric vehicle, including a front drive motor and a rear drive motor. It is understandable that the control device is different from the power system, and the control device can communicate with the power system, obtain operating parameters from the power system, and can also control the rotation of the front drive motor and the rear drive motor in the power system.

[0005] In a specific implementation, the control device obtains the driving mode of the electric vehicle, the operating parameters of the electric vehicle, and the operating parameters of the power system, and responds to the throttle signal or brake signal of the electric vehicle, and outputs the torque distribution ratio of the front drive motor and the rear drive motor according to the driving mode of the electric vehicle, the operating parameters of the electric vehicle, and the operating parameters of the power system. It should be noted that the operating parameters of the electric vehicle include the vehicle speed and the steering wheel angle, and the operating parameters of the power system include the temperature, efficiency, and operating time of the front drive motor, and the temperature, efficiency, and operating time of the rear drive motor.

[0006] The embodiments of the present application comprehensively consider the influence of motor efficiency, controller operating speed and motor life, and dynamically adjust the torque output by the motor. By implementing the embodiments of the present application, it is possible to control the motor while taking into account energy efficiency, power control and motor life, thereby improving the power, economy and reliability of electric vehicles in a balanced manner.

[0007] In combination with the first aspect, in a first possible implementation method, when the electric vehicle operates in any one of a plurality of driving modes, the control device can adjust the torque distribution ratio of the front drive motor and the rear drive motor in response to the change amplitude of any one of the operating parameters of the electric vehicle and the operating parameters of the power system exceeding a preset value.

[0008] In combination with the first aspect or the first possible implementation of the first aspect, in a second possible implementation, the control device may be specifically implemented as a vehicle controller, and the power system includes a master controller and a slave controller. Then, the vehicle controller sends control instructions to the master controller and the slave controller respectively according to the torque distribution ratio, and the master controller and the slave controller respectively adjust the torque output by the front drive motor and the rear drive motor according to the control instructions sent by the vehicle controller.

[0009] In combination with the first aspect or the first possible implementation of the first aspect, in a third possible implementation, the control device may be specifically implemented as a master controller and a slave controller. The master controller may adjust the torque output by the front drive motor according to the torque distribution ratio, and send a control instruction to the slave controller according to the torque distribution ratio of the rear drive motor, and the slave controller adjusts the torque output by the rear drive motor according to the control instruction sent by the master controller.

[0010] In combination with the first aspect or any one of the above possible implementations of the first aspect, in a fourth possible implementation, the electric vehicle includes a throttle device and a brake device, the throttle device can be triggered by a driver and output a throttle signal, and the brake device can be triggered by a driver and output a brake signal. The input end of the control device is directly connected to the throttle device and the brake device to receive the throttle signal and the brake signal.

[0011] In combination with the first aspect or any one of the above possible implementations of the first aspect, in a fifth possible implementation, the electric vehicle includes a steering angle sensing device, which can monitor the angle of the steering wheel and output a steering wheel angle signal, and the input end of the control device is directly connected to the steering angle sensing device to receive the steering wheel angle signal.

[0012] In combination with the first aspect or any one of the above possible implementations of the first aspect, in a sixth possible implementation, the front drive motor and the rear drive motor are respectively provided with a temperature sensing device, which respectively obtains the temperature of the front drive motor and the temperature of the rear drive motor and outputs a temperature signal. At this time, the control device is used to directly connect to the temperature sensing device to receive the temperature signal.

[0013] In combination with the first aspect or any one of the above possible implementations of the first aspect, in a seventh possible implementation, the control device obtains the operating parameters of the electric vehicle and the operating parameters of the power system according to the first frequency, and the control device outputs the torque distribution ratio of the front drive motor and the rear drive motor according to the second frequency. The first frequency is greater than the second frequency.

[0014] In combination with the first aspect or any one of the above possible implementations of the first aspect, in an eighth possible implementation, a plurality of torque distribution tables and a plurality of groups of weights are stored in the control device. Among them, the plurality of torque distribution tables include the correspondence between at least two parameters of the operating parameters of the electric vehicle and the operating parameters of the power system and a plurality of torque distribution reference ratios. Each group of weights in the plurality of weights corresponds to a driving mode, and each group of weights includes a plurality of weight parameters. One weight parameter in the plurality of weight parameters corresponds to a torque distribution table in the plurality of torque distribution tables. In a specific implementation, the control device searches for a plurality of torque distribution tables and determines a plurality of torque distribution reference ratios according to the operating parameters of the electric vehicle and the operating parameters of the power system; and the control device outputs the torque distribution ratio of the front-drive motor and the rear-drive motor according to a set of weights and a plurality of torque distribution reference ratios corresponding to the driving mode of the electric vehicle.

[0015] In combination with the eighth possible implementation of the first aspect, in a ninth possible implementation, the plurality of torque distribution tables include a first torque distribution table, and the plurality of torque distribution reference ratios include a first torque distribution reference ratio. The first torque distribution table includes a correspondence between the efficiency of the front drive motor, the efficiency of the rear drive motor, and the first torque distribution reference ratio, and the control device may search and determine the first torque distribution reference ratio in the first torque distribution table according to the obtained efficiency of the front drive motor and the efficiency of the rear drive motor.

[0016] In combination with the ninth possible implementation of the first aspect, in a tenth possible implementation, the plurality of torque distribution tables include a second torque distribution table, and the plurality of torque distribution reference ratios include a second torque distribution reference ratio. The second torque distribution table includes a correspondence between the temperature and operating time of the front drive motor, the temperature and operating time of the rear drive motor, and the second torque distribution reference ratio, and the control device can search and determine the second torque distribution reference ratio in the second torque distribution table according to the obtained temperature and operating time of the front drive motor and the temperature and operating time of the rear drive motor.

[0017] In combination with the tenth possible implementation manner of the first aspect, in an eleventh possible implementation manner, multiple torque distribution tables include a third torque distribution table, and multiple torque distribution reference ratios include a third torque distribution reference ratio, wherein the third torque distribution table includes the correspondence between the vehicle speed, the steering wheel angle and the third torque distribution reference ratio, and the control device can search and determine the third torque distribution reference ratio in the third torque distribution table based on the acquired vehicle speed and steering wheel angle.

[0018] In combination with the eleventh possible implementation method of the first aspect, in a twelfth possible implementation method, the control device determines a set of weights according to the driving mode of the electric vehicle; and calculates the torque distribution ratio corresponding to the driving mode of the electric vehicle based on the first torque distribution reference ratio and its corresponding weight parameters, the second torque distribution reference ratio and its corresponding weight parameters, and the third torque distribution reference ratio and its corresponding weight parameters.

[0019] In combination with the first aspect or any one of the above possible implementations of the first aspect, in the thirteenth possible implementation, the input end of the control device also obtains the speed of the electric vehicle. In an embodiment of the present application, the control device also increases the reference ratio of torque distribution for the front-drive motor in each intelligent driving mode in response to the speed of the electric vehicle being greater than the first preset speed threshold, so as to control the first inverter circuit to increase the current output to the front-drive motor. In specific practice, the front-drive motor can be a motor used to drive the front wheels, i.e., front-drive; the rear-drive motor can be a motor used to drive the rear wheels, i.e., rear-drive. Therefore, when the electric vehicle is in a high-speed driving state, the torque output by the front drive can be increased and the torque output by the rear drive can be reduced, thereby increasing the grip of the electric vehicle, avoiding vehicle slippage, and improving driving safety.

[0020] In combination with the first aspect or any one of the above possible implementations of the first aspect, in a fourteenth possible implementation, the input end of the control device also obtains the mileage information of the whole vehicle. In the embodiment of the present application, the control device also reduces the reference ratio of torque distribution for the front-drive motor in each intelligent driving mode in response to the vehicle mileage carried in the mileage information of the whole vehicle being greater than the preset mileage threshold, so as to control the first inverter circuit to reduce the current output to the front-drive motor. By implementing the embodiment of the present application, the life of the two motors can be better balanced.

[0021] In combination with the first aspect or any one of the above possible implementations of the first aspect, in a fifteenth possible implementation, the input end of the control device also obtains the steering information of the whole vehicle. In an embodiment of the present application, the control device also responds to the steering information of the whole vehicle carrying a target identifier, and increases the reference ratio of torque distribution for the rear-drive motor in each intelligent driving mode to control the controller to increase the current output from the second inverter circuit to the rear-drive motor. By implementing the present application, when the electric vehicle is in a turning state, increasing the torque output of the rear drive can help the electric vehicle turn and improve the driving performance of the electric vehicle.

[0022] In a second aspect, an embodiment of the present application provides an electric drive system, which includes a front drive motor, a rear drive motor, a first inverter circuit, a second inverter circuit, and a control device in combination with the first aspect or in combination with any one of the above possible implementation methods of the first aspect, wherein the first inverter circuit outputs current according to the torque distribution ratio of the front drive motor output by the control device to control the rotation of the front drive motor; the second inverter circuit outputs current according to the torque distribution ratio of the rear drive motor output by the control device to control the rotation of the rear drive motor.

[0023] In a third aspect, an embodiment of the present application provides an electric vehicle, comprising a power battery and an electric drive system as described in combination with the second aspect; wherein the power battery is connected to input ends of a first inverter circuit and a second inverter circuit.

[0024] It should be understood that the implementation and beneficial effects of the above-mentioned aspects of the present application can be referenced to each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of a scenario of an electric vehicle provided in an embodiment of the present application;

[0026] Figure 2 A structural block diagram of an electric drive system provided in an embodiment of the present application;

[0027] Figure 3 This is a schematic diagram of the control process of the motor in the embodiment of the present application;

[0028] Figure 4 Another structural block diagram of the electric drive system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0030] The implementation of the technical solution of the present application is further described in detail below in conjunction with the accompanying drawings.

[0031] See also Figure 1 , Figure 1 A schematic diagram of a scenario of an electric vehicle provided in an embodiment of the present application. Figure 1 As shown, the electric vehicle 10 includes an electric drive system 101 and a power battery 102 connected to the electric drive system 101 , and the power battery 102 provides power to the electric drive system 101 .

[0032] In one embodiment, the structure of the electric drive system 101 can be as follows: Figure 2 As shown, the electric drive system 101 includes a control device 201 , a first inverter circuit 202 , a front drive motor 203 , a second inverter circuit 205 and a rear drive motor 206 .

[0033] In a specific implementation, the input end of the control device 201 is connected to the brake device 207 and the throttle device 208, the output end of the control device 201 is connected to the control end of the first inverter circuit 202 and the control end of the second inverter circuit 205, and the input end of the first inverter circuit 202 and the input end of the second inverter circuit 205 are connected to the power battery. In addition, the output end of the first inverter circuit 202 is connected to the front drive motor 203, and the first inverter circuit 202 can transform the voltage of the power battery to output current to the front drive motor 203, thereby driving the front drive motor 203. The output end of the second inverter circuit 205 is connected to the rear drive motor 206, and the second inverter circuit 205 can transform the voltage of the power battery to output current to the rear drive motor 206, thereby driving the rear drive motor 206.

[0034] The control device 201 includes a main controller 2011 and a slave controller 2012. At this time, the brake device 207 and the throttle device 208 are directly connected to the input end of the main controller 2011, the output end of the main controller 2011 is specifically connected to the control end of the first inverter circuit 202, and the output end of the slave controller 2012 is specifically connected to the control end of the second inverter circuit 205. It can be understood that the brake device 207 can output a brake signal, and the throttle device 208 can output a throttle signal. Among them, the throttle signal and the brake signal are triggered by the driver stepping on the accelerator pedal or the brake pedal. In the embodiment of the present application, the brake device 207 and the throttle device 208 are directly connected to the main controller 2011, and the main controller 2011 can directly respond to the throttle signal and the brake signal, and control the torque output by the front drive motor 203 and the rear drive motor 206.

[0035] The slave controller 2012 is connected to the master controller 2011. Exemplarily, the slave controller 2012 can be directly connected to the master controller 2011, or the master controller 2011 and the slave controller 2012 are connected to a power CAN bus, and the master controller 2011 and the slave controller 2012 can communicate through the power CAN bus.

[0036] The master controller 2011 and the slave controller 2012 can be specifically implemented as a central processing unit (CPU), other general-purpose processors, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0037] The control device 201 further includes an anti-lock braking system 2013, which can calculate the vehicle speed according to the wheel speed sensed by the speed sensor, wherein the speed sensor is arranged on the wheel. Alternatively, the control device 201 further includes a vehicle body electronic stability system 2014, and in this case, the vehicle body electronic stability system 2014 can also calculate the vehicle speed according to the wheel speed sensed by the speed sensor. The specific calculation method of the vehicle speed can refer to the prior art, which will not be described here.

[0038] The communication end of the main controller 2011 is connected to the power CAN bus, and the anti-lock braking system 2013 and the body electronic stability system 2014 are also connected to the power CAN bus. Then the main controller 2011 can obtain the vehicle speed from the anti-lock braking system 2013 or the body electronic stability system 2014 through the power CAN bus.

[0039] In one embodiment, the main controller 2011 and the first inverter circuit 202 are integrated together, or the main controller 2011, the first inverter circuit 202 and the front drive motor 203 can be integrated together.

[0040] In one embodiment, the slave controller 2012 and the second inverter circuit 205 are integrated together, or the slave controller 2012, the second inverter circuit 205 and the rear drive motor 206 can be integrated together.

[0041] Exemplarily, the first inverter circuit 202 and the second inverter circuit 205 can be a three-phase two-level inverter, a three-phase three-level inverter or a three-phase multi-level inverter, that is, the embodiment of the present application does not limit the specific implementation of the first inverter circuit 202 and the second inverter circuit 205, as long as the DC power output by the power battery can be converted into AC power to drive the motor.

[0042] The following is an exemplary description of how the main controller specifically considers various factors to control the motor in conjunction with the accompanying drawings.

[0043] In one embodiment, the main controller 2011 may execute Figure 3 The control flow diagram shown in FIG. 1 shows that the main controller 2011 specifically performs the following steps:

[0044] S301, the main controller 2011 obtains the driving mode of the electric vehicle. Among them, the electric vehicle is provided with a plurality of driving modes that can be switched. It should be noted that, in the embodiment of the present application, a plurality of driving modes including a default driving mode, a first intelligent driving mode, a second intelligent driving mode and a third intelligent driving mode are taken as an example. In a specific implementation, different types of driving modes can be set according to actual applications.

[0045] In one embodiment, the driving mode may be input by the user. At this time, the main controller 2011 can obtain the driving mode of the electric vehicle by detecting the user's input. For example, a button is set corresponding to a driving mode. If the main controller 2011 detects that the button corresponding to any driving mode is pressed, it is determined that the electric vehicle is in the driving mode. It is understandable that various driving modes can also be selected by the user by clicking on the vehicle screen. The embodiment of the present application does not limit how the user specifically enters the driving mode. It can be by pressing a button or clicking on the screen.

[0046] In one embodiment, the main controller 2011 can determine the driving mode of the electric vehicle based on the operating parameters of the electric vehicle. The operating parameters of the electric vehicle include the vehicle speed, steering wheel angle, and vehicle acceleration. For example, the main controller 2011 determines that the electric vehicle is in the default driving mode when the vehicle speed is less than a first preset speed threshold. Alternatively, the main controller 2011 determines that the electric vehicle is in the default driving mode when the steering wheel angle is less than a preset angle, and so on. How to determine the driving mode of the electric vehicle based on the vehicle state can be adjusted according to actual applications and is not limited here.

[0047] S302, the main controller 2011 obtains the operating parameters of the electric vehicle and the operating parameters of the power system. The operating parameters of the electric vehicle include the vehicle speed and the steering wheel angle, and the operating parameters of the power system include the temperature, efficiency and operating time of the front drive motor 203, and the temperature, efficiency and operating time of the rear drive motor 206.

[0048] In a specific implementation, the main controller 2011 may obtain the vehicle speed and steering wheel angle from the anti-lock braking system 2013 or the vehicle electronic stability system 2014 .

[0049] Alternatively, the input end of the main controller 2011 is directly connected to the angle sensing device. In this case, the angle sensing device can monitor the angle of the steering wheel and output a steering wheel angle signal. In this case, the main controller 2011 can directly receive the steering wheel angle signal from the angle sensing device according to the first frequency. Exemplarily, the angle sensing device can be specifically implemented as a steering wheel angle sensor.

[0050] In one embodiment, the input end of the main controller 2011 is connected to a temperature sensing device, which can be arranged on the outer shell of the motor. Exemplarily, the temperature sensing device includes two temperature sensors, one temperature sensor is arranged on the outer shell of the front drive motor 203, and the other temperature sensor is arranged on the outer shell of the rear drive motor 206. At this time, the main controller 2011 can obtain the temperature of the front drive motor 203 through the temperature sensor arranged at the outer shell of the front drive motor 203, and obtain the temperature of the rear drive motor 206 through the temperature sensor arranged at the outer shell of the rear drive motor 206.

[0051] In one embodiment, the main controller 2011 can measure the efficiency of the front drive motor 203 and the rear drive motor 206 according to the vehicle speed and the throttle signal. Alternatively, the main controller 2011 can obtain the current output by the first inverter circuit 202 and the actual speed of the front drive motor 203 in real time, and calculate the efficiency of the front drive motor 203 according to the current output by the first inverter circuit 202 and the actual speed of the front drive motor 203. Similarly, the main controller 2011 can also obtain the current output by the second inverter circuit 205 and the actual speed of the rear drive motor 206 in real time, and calculate the actual speed of the rear drive motor 206 according to the current output by the second inverter circuit 205 and the actual speed of the rear drive motor 206.

[0052] In one embodiment, the main controller 2011 can obtain the vehicle mileage information from the vehicle body electronic stability system 2014 or the anti-lock braking system 2013. It is understandable that the vehicle mileage information is calculated based on the vehicle speed and the vehicle running time. The vehicle running time is related to the running time of the front drive motor 203 and the rear drive motor 206. That is, the main controller 2011 can measure the running time of the front drive motor 203 and the rear drive motor 206 according to the vehicle mileage information. For example, the front drive motor 203 is the main drive motor and the rear drive motor 206 is the auxiliary drive motor, then the main controller 2011 can determine that the running time of the front drive motor 203 is the running time of the vehicle, and the running time of the rear drive motor 206 can be a preset percentage of the running time of the vehicle, such as 90%.

[0053] S303, the main controller 2011 responds to the throttle signal or brake signal of the electric vehicle, and outputs the torque distribution ratio of the front drive motor 203 and the rear drive motor 206 according to the driving mode of the electric vehicle, the operating parameters of the electric vehicle and the operating parameters of the power system.

[0054] In a specific implementation, the main controller 2011 responds to the throttle signal or brake signal of the electric vehicle, that is, the main controller 2011 calculates the required torque of the whole vehicle according to the opening and closing degree of the throttle device 208 and the opening and closing degree of the brake device 207. Exemplarily, the main controller 2011 calculates that the required torque of the whole vehicle is 100N.

[0055] The main controller 2011 is provided with a plurality of torque distribution tables, each of which includes the correspondence between at least two parameters of the operating parameters of the electric vehicle and the operating parameters of the power system and a plurality of torque distribution reference ratios, such as the correspondence between the efficiency of the front drive motor and the efficiency of the rear drive motor and the first torque distribution reference ratio, the correspondence between the temperature and operating time of the front drive motor, the temperature and operating time of the rear drive motor and the second torque distribution reference ratio, and the correspondence between the vehicle speed and the steering wheel angle and the third torque distribution reference ratio. At this time, the main controller 2011 searches the plurality of torque distribution tables to determine and obtain a plurality of torque distribution reference ratios according to the operating parameters of the electric vehicle and the operating parameters of the power system obtained in step S302.

[0056] In one embodiment, the plurality of torque distribution tables include a first torque distribution table, which includes the correspondence between the efficiency of the front drive motor 203, the efficiency of the rear drive motor 206 and the first torque distribution reference ratio. At this time, the main controller 2011 can find and determine the first torque distribution reference ratio in the first torque distribution table according to the efficiency of the front drive motor 203 and the efficiency of the rear drive motor 206 obtained in step S302. At this time, the first torque distribution table can be understood as the torque distribution table corresponding to the first intelligent driving mode. The first intelligent driving mode is an energy consumption mode, and the energy consumption mode can be understood as the output efficiency of the front drive motor 203 and the rear drive motor 206 is high. At this time, the torque distribution reference ratio of the first intelligent driving mode for the front drive motor 203 and the rear drive motor 206 is based on the consideration of motor efficiency. Exemplarily, the torque distribution reference ratio of the first intelligent driving mode for the front drive motor 203 is expressed as 20%, and the torque distribution reference ratio of the first intelligent driving mode for the rear drive motor 206 is expressed as 80%. Alternatively, the reference ratio of torque distribution between the front drive motor 203 and the rear drive motor 206 in the first intelligent driving mode may be expressed as 2:8.

[0057] Optionally, in one embodiment, the main controller 2011 may modify the first torque distribution table according to the temperature of the front drive motor 203 and the temperature of the rear drive motor 206. For example, assuming that the efficiency of the front drive motor 203 and the efficiency of the rear drive motor 206 are the same, if the temperature of the front drive motor 203 is 10° and the temperature of the rear drive motor 206 is 20°, the main controller 2011 increases the torque distribution reference ratio of the first intelligent driving mode for the front drive motor 203 from 20% to 25%, and reduces the torque distribution reference ratio of the first intelligent driving mode for the rear drive motor 206 from 80% to 75%. Alternatively, if the temperature of the front drive motor 203 is 10° and the temperature of the rear drive motor 206 is 5°C, the main controller 2011 reduces the torque distribution reference ratio of the first intelligent driving mode for the front drive motor 203 from 20% to 18%, and increases the torque distribution reference ratio of the first intelligent driving mode for the rear drive motor 206 from 80% to 82%. In general, when the temperature of the front drive motor 203 is lower than that of the rear drive motor 206, the main controller 2011 can increase the torque output of the front drive motor 203 by increasing the reference ratio of the torque distribution of the first intelligent driving mode for the front drive motor 203, or when the temperature of the rear drive motor 206 is lower than that of the front drive motor 203, the main controller 2011 can increase the torque output of the rear drive motor 206 by increasing the reference ratio of the torque distribution of the first intelligent driving mode for the rear drive motor 206. It can be understood that the torque output of the motor is increased, the current output by the inverter circuit to the motor becomes larger, the heat generated by the magnetic loss and copper loss of the motor increases, and the speed of the motor heating up is accelerated. At this time, the heating speed of the motor to the power battery through the cooling circuit can also be increased. In the implementation of the embodiment of the present application, the reference ratio of the torque distribution of the first intelligent driving mode for the front drive motor and the rear drive motor can be further adjusted based on the temperature of the front drive motor and the temperature of the rear drive motor to adjust the torque output of the front drive motor and the rear drive motor, thereby adjusting the heating time of the front drive motor and the rear drive motor.

[0058] In one embodiment, the plurality of torque distribution tables include a second torque distribution table, which includes the corresponding relationship between the temperature and running time of the front drive motor 203, the temperature and running time of the rear drive motor 206, and the second torque distribution reference ratio. At this time, the main controller 2011 can find and determine the second torque distribution reference ratio in the second torque distribution table according to the temperature and running time of the front drive motor 203 and the temperature and running time of the rear drive motor 206 obtained in step S302. At this time, the second torque distribution table can be understood as the torque distribution table corresponding to the second intelligent driving mode. At this time, the second intelligent driving mode is a life mode, and the torque distribution reference ratio of the second intelligent driving mode for the front drive motor 203 and the rear drive motor 206 is based on the consideration of the motor life. Exemplarily, the torque distribution reference ratio of the second intelligent driving mode for the front drive motor 203 is expressed as 60%, and the torque distribution reference ratio of the second intelligent driving mode for the rear drive motor 206 is expressed as 40%. Alternatively, the torque distribution reference ratio of the second intelligent driving mode for the front drive motor 203 and the rear drive motor 206 can be expressed as 6:4.

[0059] Optionally, in one embodiment, the main controller 2011 can also obtain the remaining predicted life of the front drive motor 203 and the remaining predicted life of the rear drive motor 206 from the vehicle electronic stability system 2014 or the anti-lock braking system 2013 through the power CAN bus, or the main controller 2011 can determine the remaining predicted life of the front drive motor 203 based on the manufacturer's preset life curve of the front drive motor 203 and the working time of the front drive motor 203, and the main controller 2011 can determine the remaining predicted life of the rear drive motor 206 based on the manufacturer's preset life curve of the rear drive motor 206 and the working time of the rear drive motor 206.

[0060] At this time, the main controller 2011 can modify the second torque distribution table according to the remaining predicted life of the front drive motor 203 and the remaining predicted life of the rear drive motor 206. For example, assuming that the temperature and operating time of the front drive motor 203 are the same as the temperature and operating time of the rear drive motor 206, if the remaining predicted life of the front drive motor 203 is 500 hours and the remaining predicted life of the rear drive motor is 600 hours, the main controller 2011 reduces the torque distribution reference ratio of the second intelligent driving mode for the front drive motor 203 from 60% to 53%, and increases the torque distribution reference ratio of the second intelligent driving mode for the rear drive motor 206 from 40% to 47%. In general, when the remaining predicted life of the front drive motor 203 is less than the remaining predicted life of the rear drive motor 206, the main controller 2011 can reduce the gap between the actual remaining life of the front drive motor 203 and the actual remaining life of the rear drive motor 206 by reducing the torque distribution reference ratio of the second intelligent driving mode for the front drive motor 203.

[0061] Similarly, when the remaining predicted life of the front drive motor 203 is greater than the remaining predicted life of the rear drive motor 206, the main controller 2011 can reduce the difference between the actual remaining life of the front drive motor 203 and the actual remaining life of the rear drive motor 206 by lowering the torque distribution reference ratio for the rear drive motor 206 in the second intelligent driving mode.

[0062] By implementing the embodiments of the present application, the torque distribution reference ratio of the front drive motor and the rear drive motor in the second intelligent driving mode can be further adjusted based on the remaining predicted life of the front drive motor and the remaining predicted life of the rear drive motor, so as to adjust the torque output by the front drive motor and the rear drive motor, thereby adjusting the actual remaining life of the front drive motor and the rear drive motor.

[0063] In one embodiment, the plurality of torque distribution tables include a third torque distribution table, which includes a correspondence between the vehicle speed, the steering wheel angle and the third torque distribution reference ratio. At this time, the main controller 2011 can find and determine the third torque distribution reference ratio in the third torque distribution table according to the vehicle speed and the steering wheel angle obtained in step S302. At this time, the third torque distribution table can be understood as a torque distribution table corresponding to the third intelligent driving mode. The third intelligent driving mode is a performance mode, and the performance mode can be understood as a large operating rate of the main controller 2011. At this time, the torque distribution reference ratio of the third intelligent driving mode for the front drive motor 203 and the rear drive motor 206 is based on the operating rate of the main controller 2011. Exemplarily, the torque distribution reference ratio of the third intelligent driving mode for the front drive motor 203 is expressed as 50%, and the torque distribution reference ratio of the third intelligent driving mode for the rear drive motor 206 is expressed as 50%. Alternatively, the torque distribution reference ratio of the third intelligent driving mode for the front drive motor 203 and the rear drive motor 206 can be expressed as 5:5.

[0064] Optionally, in one embodiment, the main controller 2011 may modify the third torque distribution table according to the temperature of the front drive motor 203 and the temperature of the rear drive motor 206. For example, assuming that the vehicle speed and the steering wheel angle are the same, if the temperature of the front drive motor 203 is 10° and the temperature of the rear drive motor 206 is 20°, the main controller 2011 increases the torque distribution reference ratio of the third intelligent driving mode for the front drive motor 203 from 50% to 55%, and reduces the torque distribution ratio of the third intelligent driving mode for the rear drive motor 206 from 50% to 45%. Alternatively, if the temperature of the front drive motor 203 is 10° and the temperature of the rear drive motor 206 is 5°C, the main controller 2011 reduces the torque distribution reference ratio of the third intelligent driving mode for the front drive motor 203 from 50% to 45%, and increases the torque distribution reference ratio of the third intelligent driving mode for the rear drive motor 206 from 50% to 55%. In general, when the temperature of the front drive motor 203 is lower than that of the rear drive motor 206, the main controller 2011 can increase the torque output by the front drive motor 203 by increasing the reference ratio of torque distribution for the front drive motor 203 in the third intelligent driving mode, or when the temperature of the rear drive motor 206 is lower than that of the front drive motor 203, the main controller 2011 can increase the torque output by the rear drive motor 206 by increasing the reference ratio of torque distribution for the rear drive motor 206 in the third intelligent driving mode. It can be understood that when the torque output by the motor is increased, the current output by the inverter circuit to the motor becomes larger, the heat generated by the magnetic loss and copper loss of the motor increases, and the speed of heating the motor is accelerated. At this time, the speed at which the motor heats the power battery through the cooling circuit can also be increased.

[0065] By implementing the embodiment of the present application, the torque distribution reference ratio of the front drive motor and the rear drive motor in the third intelligent driving mode can be further adjusted based on the temperature of the front drive motor and the temperature of the rear drive motor to adjust the torque output by the front drive motor and the rear drive motor, thereby adjusting the temperature difference between the front drive motor and the rear drive motor.

[0066] In one embodiment, the multiple driving modes also include a default driving mode, and the reference ratio of torque distribution for the front drive motor 203 and the rear drive motor 206 in the default driving mode is preset. For example, the reference ratio of torque distribution for the front drive motor 203 in the default driving mode is 70%, and the reference ratio of torque distribution for the rear drive motor 206 in the default driving mode is 30%. That is, the torque output by the front drive motor 203 is 70% of the torque required by the whole vehicle, and the torque output by the rear drive motor 206 is 30% of the torque required by the whole vehicle.

[0067] The above is a specific implementation method for determining the reference ratio of torque distribution for the front-wheel drive motor and the rear-wheel drive motor for each driving mode. It can be seen that the first intelligent driving mode is based on motor efficiency, the second intelligent driving mode is based on the operating rate of the controller, and the third intelligent driving mode is based on motor life.

[0068] The main controller 2011 may determine the torque distribution ratio between the front drive motor and the rear drive motor according to a reference torque distribution ratio between the front drive motor and the rear drive motor and a set of weights corresponding to the driving mode of the electric vehicle.

[0069] In a specific implementation, each driving mode corresponds to a set of weights, and each set of weights includes multiple weight parameters, and one weight parameter corresponds to a torque distribution table. The corresponding relationship between various driving modes and each set of weights is preset, and the corresponding relationship between each weight parameter and the torque distribution table is preset.

[0070] Exemplarily, the main controller 2011 determines the first set of weights corresponding to the first intelligent driving mode when it is obtained that the electric vehicle is in the first intelligent driving mode. The first set of weights includes three weight parameters. Exemplarily, the three weight parameters in the first set of weights are 0.8, 0.1 and 0.1 respectively. Then, when the electric vehicle is in the first intelligent driving mode, the weight parameter corresponding to the first torque distribution table is 0.8, the weight parameter corresponding to the second torque distribution table is 0.1, and the weight parameter corresponding to the third torque distribution table is 0.1. There is also a corresponding relationship between each torque distribution table and the driving mode, so it can also be said that when the electric vehicle is in the first intelligent driving mode, the weight parameter corresponding to the first intelligent driving mode is 0.8, the weight parameter corresponding to the second intelligent driving mode is 0.1, and the weight parameter corresponding to the third intelligent driving mode is 0.1. It can be seen that the sum of the weight parameters of all intelligent driving modes is 1, that is, the sum of the weight parameters of the first intelligent driving mode, the weight parameters of the second intelligent driving mode and the weight parameters of the third intelligent driving mode is 1.

[0071] In one embodiment, the main controller 2011 can obtain the torque distribution ratio of the first intelligent driving mode for the front drive motor 203 and the rear drive motor 206 according to each weight parameter in the first group of weights corresponding to the first intelligent driving mode and the torque distribution reference ratio corresponding to each weight parameter. It should be explained that the torque distribution ratio of the front drive motor 203 and the rear drive motor 206 is the actual torque distribution ratio of the front drive motor 203 and the rear drive motor 206.

[0072] Exemplarily, when the electric vehicle is in the first intelligent driving mode, the main controller 2011 determines a first set of weights, and the three weight parameters included in the first set of weights are 0.8, 0.1, and 0.1. In addition, the main controller 2011 searches and determines in the first torque distribution table that the first torque distribution reference ratio is expressed as 2:8 according to the efficiency of the front drive motor 203 and the efficiency of the rear drive motor 206, that is, the torque distribution reference ratio of the first intelligent driving mode for the front drive motor 203 is 20%, and the torque distribution reference ratio of the first intelligent driving mode for the rear drive motor 206 is 80%. The main controller 2011 searches and determines in the second torque distribution table that the second torque distribution reference ratio is expressed as 6:4 according to the temperature and operating time of the front drive motor 203 and the temperature and operating time of the rear drive motor 206, that is, the torque distribution reference ratio of the second intelligent driving mode for the front drive motor 203 is 60%, and the torque distribution reference ratio of the second intelligent driving mode for the rear drive motor 206 is 40%. The main controller 2011 searches the third torque distribution table according to the vehicle speed and the steering wheel angle to determine that the third torque distribution reference ratio is 5:5, that is, the torque distribution reference ratio of the third intelligent driving mode for the front drive motor 203 is 50%, and the torque distribution reference ratio of the third intelligent driving mode for the rear drive motor 206 is 50%.

[0073] Among them, the weight parameter corresponding to the first torque distribution reference ratio is 0.8, the weight parameter corresponding to the second torque distribution reference ratio is 0.1, and the weight parameter corresponding to the third torque distribution reference ratio is 0.1. At this time, the main controller 2011 adds the results obtained by multiplying each torque distribution reference ratio by the weight parameter corresponding to each torque distribution reference ratio, and obtains the actual torque distribution ratio of the electric vehicle for the front drive motor 203 and the rear drive motor 206 in the first intelligent driving mode. The actual torque distribution ratio of the first intelligent driving mode for the front drive motor 203 is specifically expressed by the formula: 20%×0.8+50%×0.1+60%×0.1=27%; the actual torque distribution ratio of the first intelligent driving mode for the rear drive motor 206 is specifically expressed by the formula: 80%×0.8+50%×0.1+40%×0.1=73%.

[0074] The main controller 2011 determines the torque output by the front drive motor 203 and the rear drive motor 206 when the electric vehicle is in the first intelligent driving mode according to the actual torque distribution ratio of the front drive motor 203 and the rear drive motor 206 in the first intelligent driving mode and the required torque of the whole vehicle. For example, the required torque of the whole vehicle is 100N, and when the electric vehicle is in the first intelligent driving mode, the torque output by the front drive motor 203 is 100×27%=27, and the torque output by the rear drive motor 206 is 100×73%=73.

[0075] At this time, the main controller 2011 can control the current output by the first inverter circuit 202 to the front drive motor 203, thereby controlling the torque output by the front drive motor 203 to be 27N. In addition, the main controller 2011 can send a control instruction to the slave controller 2012, and the control instruction carries the torque output by the rear drive motor 206. The slave controller 2012 controls the current output by the second inverter circuit 205 to the rear drive motor 206, thereby controlling the torque output by the rear drive motor 206 to be 73N.

[0076] In one embodiment, the main controller 2011 can obtain the torque distribution ratio of the second intelligent driving mode for the front drive motor 203 and the rear drive motor 206 based on each weight parameter in the second group of weights corresponding to the second intelligent driving mode and the torque distribution reference ratio corresponding to each weight parameter.

[0077] Exemplarily, when the electric vehicle is in the second intelligent driving mode, the main controller 2011 determines a second set of weights, and the three weight parameters of the second set of weights are 0.25, 0.25 and 0.5.

[0078] It should be noted that when the electric vehicle switches from the first intelligent driving mode to the second intelligent driving mode, the torque distribution reference ratios of the various intelligent driving modes for the front drive motor 203 and the rear drive motor 206 do not change, but the weight parameters corresponding to the various intelligent driving modes in the second intelligent driving mode are changed. That is, the first torque distribution reference ratio is still 2:8, that is, the torque distribution reference ratio of the first intelligent driving mode for the front drive motor 203 is 20%, and the torque distribution reference ratio of the first intelligent driving mode for the rear drive motor 206 is 80%. The second torque distribution reference ratio is still 6:4, that is, the torque distribution reference ratio of the second intelligent driving mode for the front drive motor 203 is 60%, and the torque distribution reference ratio of the second intelligent driving mode for the rear drive motor 206 is 40%. The third torque distribution reference ratio is still 5:5, that is, the torque distribution reference ratio of the third intelligent driving mode for the front drive motor 203 is 50%, and the torque distribution reference ratio of the third intelligent driving mode for the rear drive motor 206 is 50%.

[0079] Among them, the weight parameter corresponding to the first torque distribution reference ratio is 0.25, the weight parameter corresponding to the second torque distribution reference ratio is 0.25, and the weight parameter corresponding to the third torque distribution reference ratio is 0.5. At this time, the actual torque distribution ratio of the front drive motor 203 is specifically expressed by the formula: 20%×0.25+50%×0.25+60%×0.5=47.5%; the actual torque distribution ratio of the rear drive motor 206 is specifically expressed by the formula: 80%×0.25+50%×0.25+40%×0.5=52.5%.

[0080] The main controller 2011 determines the torque output by the front drive motor 203 and the rear drive motor 206 when the electric vehicle is in the second intelligent driving mode according to the actual torque distribution ratio of the front drive motor 203 and the rear drive motor 206 in the second intelligent driving mode and the required torque of the whole vehicle. For example, if the required torque of the whole vehicle is 100N, when the electric vehicle is in the second intelligent driving mode, the torque output by the front drive motor 203 is 100×47.5%=47.5, and the torque output by the rear drive motor 206 is 100×52.5%=52.5.

[0081] At this time, the main controller 2011 can control the current output by the first inverter circuit 202 to the front drive motor 203, thereby controlling the torque output by the front drive motor 203 to be 47.5N. In addition, the main controller 2011 can send a control instruction to the slave controller 2012, and the control instruction carries the torque output by the rear drive motor 206. The slave controller 2012 controls the current output by the second inverter circuit 205 to the rear drive motor 206, thereby controlling the torque output by the rear drive motor 206 to be 52.5N.

[0082] In one embodiment, the main controller 2011 can obtain the torque distribution ratio of the third intelligent driving mode for the front drive motor 203 and the rear drive motor 206 based on each weight parameter in the third group of weights corresponding to the third intelligent driving mode and the torque distribution reference ratio corresponding to each weight parameter.

[0083] Exemplarily, when the electric vehicle is in the third intelligent driving mode, the main controller 2011 determines a third set of weights, and the three weight parameters of the third set of weights are 0.25, 0.5 and 0.25.

[0084] Similarly, when the electric vehicle switches from the first intelligent driving mode or the second intelligent driving mode to the third intelligent driving mode, the torque distribution reference ratios of the various intelligent driving modes for the front drive motor 203 and the rear drive motor 206 do not change, and what changes are the weight parameters corresponding to the various intelligent driving modes in the third intelligent driving mode. That is, the first torque distribution reference ratio is still 2:8, that is, the torque distribution reference ratio of the first intelligent driving mode for the front drive motor 203 is 20%, and the torque distribution reference ratio of the first intelligent driving mode for the rear drive motor 206 is 80%. The second torque distribution reference ratio is still 6:4, that is, the torque distribution reference ratio of the second intelligent driving mode for the front drive motor 203 is 60%, and the torque distribution reference ratio of the second intelligent driving mode for the rear drive motor 206 is 40%. The third torque distribution reference ratio is still 5:5, that is, the torque distribution reference ratio of the third intelligent driving mode for the front drive motor 203 is 50%, and the torque distribution reference ratio of the third intelligent driving mode for the rear drive motor 206 is 50%.

[0085] Among them, the weight parameter corresponding to the first torque distribution reference ratio is 0.25, the weight parameter corresponding to the second torque distribution reference ratio is 0.5, and the weight parameter corresponding to the third torque distribution reference ratio is 0.25. At this time, the actual torque distribution ratio of the front drive motor 203 is specifically expressed by the formula: 20%×0.25+50%×0.5+60%×0.25=45%; the actual torque distribution ratio of the rear drive motor 206 is specifically expressed by the formula: 80%×0.25+50%×0.5+40%×0.25=55%.

[0086] The main controller 2011 determines the torque output by the front drive motor 203 and the rear drive motor 206 when the electric vehicle is in the third intelligent driving mode according to the actual torque distribution ratio of the front drive motor 203 and the rear drive motor 206 in the third intelligent driving mode and the required torque of the whole vehicle. For example, if the required torque of the whole vehicle is 100N, when the electric vehicle is in the third intelligent driving mode, the torque output by the front drive motor 203 is 100×45%=45, and the torque output by the rear drive motor 206 is 100×55%=55.

[0087] At this time, the main controller 2011 can control the current output by the first inverter circuit 202 to the front drive motor 203, thereby controlling the torque output by the front drive motor 203 to be 45N. In addition, the main controller 2011 can send a control instruction to the slave controller 2012, and the control instruction carries the torque output by the rear drive motor 206. The slave controller 2012 controls the current output by the second inverter circuit 205 to the rear drive motor 206, thereby controlling the torque output by the rear drive motor 206 to be 55N.

[0088] In summary, under different intelligent driving modes, the weight parameters corresponding to each intelligent driving mode are different. Therefore, under different intelligent driving modes, the torque distribution ratio obtained by adjusting the weight parameters corresponding to each intelligent driving mode is different. It can be seen that the embodiment of the present application comprehensively considers the influence of motor efficiency, controller operation rate and motor life, and dynamically adjusts the torque output by the motor. By implementing the embodiment of the present application, the motor can be controlled by taking into account energy efficiency, power control and motor service life, and the power, economy and reliability of the electric vehicle can be balanced.

[0089] In one embodiment, the main controller 2011 adjusts the torque distribution ratio of the front drive motor 203 and the rear drive motor 206 in response to the change amplitude of any one of the operating parameters of the electric vehicle and the operating parameters of the power system exceeding the preset value. For example, if the vehicle speed is greater than the first preset speed threshold, even if the electric vehicle does not switch the driving mode, the main controller 2011 changes the third torque distribution reference ratio determined by searching in the third torque distribution table according to the vehicle speed, so that under the same weight parameter, the torque distribution ratio of the front drive motor 203 and the rear drive motor 206 changes. Alternatively, if the main controller 2011 detects that the vehicle speed is greater than the first preset speed threshold, if the electric vehicle is in the first intelligent driving mode, the second intelligent driving mode or the default driving mode, the main controller 2011 switches the electric vehicle to the third intelligent driving mode, so that the torque distribution ratio of the front drive motor 203 and the rear drive motor 206 changes.

[0090] In one embodiment, the main controller 2011 obtains the operating parameters of the electric vehicle and the operating parameters of the power system according to the first frequency, and the main controller 2011 outputs the torque distribution ratio of the front drive motor 203 and the rear drive motor 206 according to the second frequency. The first frequency is greater than the second frequency. At this time, the main controller 2011 can perform multiple average operations on the motion parameters of the electric vehicle and the motion parameters of the power system before outputting the torque distribution ratio of the front drive motor 203 and the rear drive motor 206. At this time, the torque distribution ratio of the front drive motor 203 and the rear drive motor 206 obtained is more accurate.

[0091] In one embodiment, no matter the electric vehicle is in the first intelligent driving mode, the second intelligent driving mode or the third intelligent driving mode, when the main controller 2011 detects that the speed of the electric vehicle is greater than the second preset speed threshold, the main controller 2011 increases the torque distribution reference ratio for the front drive motor 203 in each intelligent driving mode, and controls the first inverter circuit 202 to increase the current output to the front drive motor 203. At this time, the torque output by the front drive motor 203 increases.

[0092] Exemplarily, the main controller 2011 searches the first torque distribution table to determine that the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode is 20%, and the reference ratio of torque distribution for the rear drive motor 206 in the first intelligent driving mode is 80%. If the main controller 2011 detects that the speed of the electric vehicle is greater than the second preset speed threshold, the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode is increased, for example, increased to 25%. Since the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode and the reference ratio of torque distribution for the rear drive motor 206 in the first intelligent driving mode add up to 100%, then at this time, the reference ratio of torque distribution for the rear drive motor 206 in the first intelligent driving mode is 75%. It should be explained that when the speed of the electric vehicle is greater than the second preset speed threshold, it can be considered that the electric vehicle is in a high-speed driving state. That is, when the electric vehicle is in a high-speed driving state, the main controller 2011 can increase the reference ratio of the torque distribution of the front drive motor 203 in the first intelligent driving mode according to aerodynamics, thereby increasing the torque output by the front drive motor 203 and reducing the torque output by the rear drive motor 206. In specific practice, the front drive motor 203 can be a motor used to drive the front wheels, that is, the front drive; the rear drive motor 206 can be a motor used to drive the rear wheels, that is, the rear drive. Therefore, when the electric vehicle is in a high-speed driving state, the torque output by the front drive can be increased and the torque output by the rear drive can be reduced, thereby increasing the grip of the electric vehicle, avoiding the vehicle from slipping, and improving driving safety.

[0093] In one embodiment, no matter the electric vehicle is in the first intelligent driving mode, the second intelligent driving mode or the third intelligent driving mode, when the main controller 2011 detects that the mileage of the electric vehicle is greater than the preset mileage threshold, the main controller 2011 reduces the reference ratio of torque distribution for the front drive motor 203 in each intelligent driving mode, and controls the first inverter circuit 202 to reduce the current output to the front drive motor 203. At this time, the torque output by the front drive motor 203 is reduced.

[0094] Exemplarily, the main controller 2011 searches the first torque distribution table to determine that the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode is 20%, and the reference ratio of torque distribution for the rear drive motor 206 in the first intelligent driving mode is 80%. If the main controller 2011 detects that the mileage of the electric vehicle is greater than the preset mileage threshold, the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode is reduced, for example, to 15%. Since the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode and the reference ratio of torque distribution for the rear drive motor 206 in the first intelligent driving mode add up to 100%, then the reference ratio of torque distribution for the rear drive motor 206 in the first intelligent driving mode is 85%. It should be explained that there are two motors in the vehicle, and these two motors can be different types of motors, for example, the front drive motor 203 is a synchronous motor, and the rear drive motor 206 is an asynchronous motor. Generally speaking, the synchronous motor is the main drive motor, that is, the front drive motor 203 is the main drive motor. During vehicle driving, the main drive motor performs more work externally. If the mileage of the electric vehicle is greater than a preset mileage threshold, it can be considered that the main drive motor is overworked, and the main controller 2011 reduces the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode, thereby reducing the torque output by the front drive motor 203 and increasing the torque output by the rear drive motor 206. By implementing the embodiment of the present application, the main drive motor can be prevented from being overworked and the auxiliary drive motor can be idle, and the life of the two motors can be better balanced.

[0095] In one embodiment, the main controller 2011 can also obtain the steering information of the electric vehicle from the vehicle electronic stability system 2014 or the anti-lock braking system 2013 through the power CAN bus, or the input end of the main controller 2011 can be connected to a steering sensor to obtain the steering information of the electric vehicle from the steering sensor.

[0096] Regardless of whether the electric vehicle is in the first intelligent driving mode, the second intelligent driving mode or the third intelligent driving mode, when the main controller 2011 detects that the steering information of the electric vehicle carries a target identifier, the target identifier is used to determine that the electric vehicle is in a turning state. At this time, the main controller 2011 increases the torque distribution reference ratio for the rear drive motor 206 in each intelligent driving mode, and controls the second inverter circuit 205 to increase the current output to the rear drive motor 206. At this time, the torque output by the rear drive motor 206 increases.

[0097] Exemplarily, the main controller 2011 searches the first torque distribution table to determine that the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode is 20%, and the reference ratio of torque distribution for the rear drive motor 206 in the first intelligent driving mode is 80%. If the main controller 2011 determines that the electric vehicle is in a turning state, the reference ratio of torque distribution for the rear drive motor 206 in the first intelligent driving mode is increased, for example, to 83%. Since the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode and the reference ratio of torque distribution for the rear drive motor 206 in the first intelligent driving mode are added to 100%, then the reference ratio of torque distribution for the front drive motor 203 in the first intelligent driving mode is 17%. In specific practice, the front drive motor 203 can be a motor used to drive the front wheels, that is, the front drive; the rear drive motor 206 can be a motor used to drive the rear wheels, that is, the rear drive. Therefore, when the electric vehicle is in a turning state, increasing the torque output by the rear drive can help the electric vehicle turn and improve the driving performance of the electric vehicle.

[0098] In one embodiment, the structure of the electric drive system 101 can be as follows: Figure 4 As shown, the electric drive system 101 includes a control device 401 , a first inverter circuit 402 , a front drive motor 403 , a second inverter circuit 405 and a rear drive motor 406 .

[0099] The input end of the control device 401 is connected to the brake device 407 and the throttle device 408. Figure 2 The control device 201 shown in the figure, the control device 401 provided in the embodiment of the present application includes a vehicle controller 4012, and the power system includes a main controller 400 and a slave controller 404.

[0100] At this time, the brake device 407 and the throttle device 408 are specifically connected to the vehicle controller 4012, and the output end of the vehicle controller 4012 is connected to the power CAN bus. The input ends of the master controller 400 and the slave controller 404 are connected to the power CAN bus. The output end of the master controller 400 is connected to the control end of the first inverter circuit 402, the output end of the slave controller 404 is connected to the control end of the second inverter circuit 405, and the input end of the first inverter circuit 402 and the input end of the second inverter circuit 405 are connected to the power battery. In addition, the output end of the first inverter circuit 402 is connected to the front drive motor 403, and the first inverter circuit 402 can transform the voltage of the power battery to output current to the front drive motor 403, thereby driving the front drive motor 403. The output end of the second inverter circuit 405 is connected to the rear drive motor 406, and the second inverter circuit 405 can transform the voltage of the power battery to output current to the rear drive motor 406, thereby driving the rear drive motor 406.

[0101] In one embodiment, the master controller 400 is connected to a communication terminal of the slave controller 404 .

[0102] In a specific implementation, the vehicle controller 4012 obtains the driving mode of the electric vehicle, the operating parameters of the electric vehicle, and the operating parameters of the power system, and the vehicle controller 4012 responds to the throttle signal or brake signal of the electric vehicle, and outputs the torque distribution ratio of the front drive motor 403 and the rear drive motor 406 according to the driving mode of the electric vehicle, the operating parameters of the electric vehicle, and the operating parameters of the power system. For specific implementation methods, refer to the description of steps S301 to S303.

[0103] The difference is that in the embodiment of the present application, the torque distribution ratio of the front drive motor 403 and the rear drive motor 406 is determined by the vehicle controller 4012, or the torque output by the front drive motor 403 and the rear drive motor 406 is calculated directly based on the required torque of the vehicle and the torque distribution ratio of the front drive motor 403 and the rear drive motor 406.

[0104] The first torque distribution table, the second torque distribution table, the third torque distribution table and the weight parameters corresponding to each torque distribution table are all set in the vehicle controller 4012.

[0105] In one embodiment, the vehicle controller 4012 can calculate the torque output by the front drive motor 403 and the rear drive motor 406 , and send the torque output by the front drive motor 403 to the main controller 400 , and send the torque output by the rear drive motor 406 to the slave controller 404 .

[0106] Optionally, in one embodiment, the vehicle controller 4012 can send the vehicle's required torque, multiple torque distribution tables and their corresponding weight parameters to the main controller 400 and the slave controller 404, so that the main controller 400 controls the current output by the first inverter circuit 402 to the front-drive motor 403 based on the vehicle's required torque, the first torque distribution table, the second torque distribution table, the third torque distribution table and the weight parameters corresponding to each torque distribution table; the slave controller 404 controls the current output by the second inverter circuit 405 to the rear-drive motor 406 based on the vehicle's required torque, the first torque distribution table, the second torque distribution table, the third torque distribution table and the weight parameters corresponding to each torque distribution table.

[0107] It can be seen that Figure 4 The electric drive system shown in FIG. 1 is only used by the vehicle controller 4012 to obtain the driving mode of the electric vehicle, the operating parameters of the electric vehicle and the operating parameters of the power system, and output the torque distribution ratio of the front drive motor 403 and the rear drive motor 406. The embodiment of the present application can still be implemented as follows Figure 2The effect described in, that is, taking into account the influence of motor efficiency, controller operating speed and motor life, dynamically adjusting the torque output by the motor, and implementing the embodiments of the present application can take into account energy efficiency, power control and motor life, and improve the power, economy and reliability of electric vehicles in a balanced manner.

[0108] It should be noted that the above terms “first” and “second” are only used for descriptive purposes and should not be understood as indicating or implying relative importance.

[0109] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A control device for an electric vehicle power system, It is characterized in that The electric vehicle includes multiple driving modes, the power system includes a front drive motor and a rear drive motor, the control device is used to control the torque distribution ratio of the front drive motor and the rear drive motor in the power system, and the control device is used to: Acquiring a driving mode of the electric vehicle; Acquiring operating parameters of the electric vehicle according to the first frequency, wherein the operating parameters of the electric vehicle include vehicle speed and steering wheel angle; Acquiring operating parameters of the power system according to the first frequency, the operating parameters of the power system including the temperature, efficiency and operating time of the front drive motor and the rear drive motor; In response to a throttle signal or a brake signal of the electric vehicle, outputting a torque distribution ratio of the front drive motor and the rear drive motor at a second frequency according to a driving mode of the electric vehicle, an operating parameter of the electric vehicle and an operating parameter of the power system; The first frequency is greater than the second frequency.

2. The control device according to claim 1, It is characterized in that When the electric vehicle is running in any one of the multiple driving modes, the control device is used to: In response to a change in any one of the operating parameters of the electric vehicle and the operating parameters of the power system exceeding a preset value, the torque distribution ratio of the front drive motor and the rear drive motor is adjusted.

3. The control device according to claim 1, It is characterized in that The control device includes a vehicle controller, and the power system includes a master controller and a slave controller, wherein: The vehicle controller is used to send control instructions to the main controller and the slave controller respectively according to the torque distribution ratio; The main controller and the slave controller are used to adjust the torque output by the front drive motor and the rear drive motor respectively according to the control instructions sent by the vehicle controller.

4. The control device according to claim 1, It is characterized in that The control device comprises a master controller and a slave controller, wherein: The main controller is used to adjust the torque output by the front drive motor according to the torque distribution ratio, and send a control instruction to the slave controller according to the torque distribution ratio of the rear drive motor; The slave controller is used to adjust the torque output by the rear drive motor according to the control instruction sent by the master controller.

5. According to the control device according to claim 1, the electric vehicle includes a throttle device and a brake device, the throttle device is used to receive a trigger and output the throttle signal, the brake device is used to receive a trigger and output the brake signal, and the input end of the control device is used to directly connect the throttle device and the brake device to receive the throttle signal and the brake signal.

6. According to the control device of claim 1, the electric vehicle includes a steering angle sensing device, the steering angle sensing device is used to monitor and output the steering wheel angle signal, and the input end of the control device is used to directly connect to the steering angle sensing device to receive the steering wheel angle signal.

7. The control device according to claim 1, It is characterized in that The front drive motor and the rear drive motor are respectively provided with a temperature sensing device, and the temperature sensing device is used to obtain the temperature of the front drive motor and the temperature of the rear drive motor and output a temperature signal. The control device is used to directly connect to the temperature sensing device to receive the temperature signal.

8. The control device according to any one of claims 1 to 7, It is characterized in that The control device includes a plurality of torque distribution tables and a plurality of weight groups, wherein the plurality of torque distribution tables include a correspondence between at least two parameters among the operating parameters of the electric vehicle and the operating parameters of the power system and a plurality of torque distribution reference ratios, each of the plurality of weight groups corresponds to a driving mode, and each of the plurality of weight groups includes a plurality of weight parameters, and one of the plurality of weight parameters corresponds to one of the plurality of torque distribution tables, and the control device is used to: According to the operating parameters of the electric vehicle and the operating parameters of the power system, searching the plurality of torque distribution tables and determining a plurality of torque distribution reference ratios; The torque distribution ratio of the front drive motor and the rear drive motor is outputted according to a set of the weights corresponding to the driving mode of the electric vehicle and the plurality of torque distribution reference ratios.

9. The control device according to claim 8, It is characterized in that The plurality of torque distribution tables include a first torque distribution table, the plurality of torque distribution reference ratios include a first torque distribution reference ratio, wherein the first torque distribution table includes a correspondence between the efficiency of the front drive motor, the efficiency of the rear drive motor and the first torque distribution reference ratio, and the control device is further configured to: The first torque distribution reference ratio is determined by searching in the first torque distribution table according to the obtained efficiency of the front drive motor and the efficiency of the rear drive motor.

10. The control device according to claim 9, It is characterized in that The plurality of torque distribution tables include a second torque distribution table, the plurality of torque distribution reference ratios include a second torque distribution reference ratio, wherein the second torque distribution table includes a correspondence between the temperature and operating time of the front drive motor, the temperature and operating time of the rear drive motor, and the second torque distribution reference ratio, and the control device is further used for: The second torque distribution reference ratio is determined by searching in the second torque distribution table according to the acquired temperature and operating time of the front drive motor and the acquired temperature and operating time of the rear drive motor.

11. The control device according to claim 10, It is characterized in that The plurality of torque distribution tables include a third torque distribution table, the plurality of torque distribution reference ratios include a third torque distribution reference ratio, wherein the third torque distribution table includes a correspondence between a vehicle speed, a steering wheel angle and the third torque distribution reference ratio, and the control device is further configured to: The third torque distribution reference ratio is determined by searching in the third torque distribution table according to the acquired vehicle speed and the steering wheel angle.

12. The control device according to claim 11, It is characterized in that The control device is used to: Determining a set of weights according to a driving mode of the electric vehicle; The torque distribution ratio corresponding to the driving mode of the electric vehicle is calculated based on the first torque distribution reference ratio and its corresponding weight parameter, the second torque distribution reference ratio and its corresponding weight parameter, and the third torque distribution reference ratio and its corresponding weight parameter.

13. An electric drive system, It is characterized in that The electric drive system includes a front-drive motor, a rear-drive motor, a first inverter circuit, a second inverter circuit, and a control device as described in any one of claims 1 to 12, wherein the first inverter circuit is used to output current to drive the front-drive motor, the second inverter circuit is used to output current to drive the rear-drive motor, and the first inverter circuit and the second inverter circuit are respectively used to adjust the output current according to the torque distribution ratio output by the control device.

14. An electric vehicle, It is characterized in that The electric vehicle comprises a power battery and the electric drive system as claimed in claim 13.

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