Vehicle torque distribution control method and device, vehicle, storage medium and electronic equipment

Abstract

The application provides a vehicle torque distribution control method, device, vehicle, storage medium and electronic equipment. The vehicle torque distribution control method sets a torque distribution condition: starting the vehicle, collecting data of vehicle related subsystems; calculating wheel speed of the vehicle and slip rate of the driving axle wheel; in the process that the motor drives the vehicle to move forward when the accelerator pedal is stepped on, calculating total torque of the vehicle and determining the satisfied distribution condition, and distributing target torque sent to each motor according to the distribution condition. The application improves the overall performance of the centralized driving dual motor vehicle by comprehensively considering real-time working conditions of the vehicle and reasonably controlling distribution and output of the dual motor torque, and is especially suitable for a multi-module articulated vehicle using dual motor centralized driving.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of motor control, and particularly relates to a vehicle torque distribution control method and device, a vehicle, a storage medium and an electronic device, which are suitable for motor torque distribution of a double-motor articulated vehicle with centralized driving. BACKGROUND

[0002] With the improvement of environmental awareness and the rapid development of new energy vehicle technology, electric vehicles have gradually become the main development direction of modern transportation. At the same time, in the field of public transportation, a multi-formation articulated electronic guide rubber wheel vehicle has a strong prospect in the medium and low volume market of urban public transportation due to the combination of the advantages of large capacity and stable operation of rail vehicles and the convenience and flexibility of buses without rail. This multi-formation articulated electronic guide rubber wheel vehicle has the characteristics of flexible formation and double-end driving without turning, and usually adopts distributed driving or provides sufficient traction power.

[0003] For a double-motor electric vehicle with centralized driving, the traditional torque distribution method is mainly based on experience or fixed torque distribution ratio. This distribution method does not fully consider the real-time working condition of the vehicle, and often cannot achieve the best power and economy. For example, when the vehicle starts, accelerates, decelerates, turns or drives on different road conditions, the fixed torque distribution ratio may not provide the best driving performance and stability.

[0004] In recent years, with the development of control theory and computer technology, model-based torque distribution control methods have gradually attracted attention. These methods establish a vehicle dynamics model and combine real-time sensor data to dynamically distribute the torque of the double motor, such as the double-motor torque distribution control method of the rubber wheel low-floor intelligent rail train disclosed in patent publication No. CN105291887A. Although this method can theoretically improve vehicle performance, due to model errors, sensor noise, external disturbances and controller real-time computing power, it is often difficult to achieve ideal results in practical applications. SUMMARY

[0005] The purpose of the present application is to provide a vehicle torque distribution control method, device, vehicle, storage medium and electronic device, which aims to improve the overall performance of the centralized driving double-motor vehicle by considering the real-time working condition of the vehicle and reasonably controlling the distribution and output of the double-motor torque, especially suitable for multi-module articulated vehicles using double-motor centralized driving.

[0006] The technical solution of the present application is: a vehicle torque distribution control method, comprising:

[0007] Collect data from vehicle related subsystems, such as vehicle speed, drive axle wheel speed, current motor speed, feedback torque, battery pack voltage and maximum current, throttle pedal travel percentage and brake pedal travel percentage. For multi-module vehicle, i.e. with multiple carriages, the relative angle of drive axle to vehicle body and the angle or steering wheel angle of adjacent carriage can be collected additionally to improve the effect.

[0008] When the data provided by the vehicle related subsystems are not accurate enough or cannot provide the required data directly, the method further includes improving the data accuracy or obtaining the required data through data processing methods such as filtering, data fusion, formula calculation, integration and difference. In addition to the above-mentioned subsystem data, at least the drive axle wheel slip ratio, the maximum torque at the current motor speed and the maximum power of the power system are required. Through data fusion and filter, the accuracy of vehicle speed and wheel speed is improved, and the accuracy of slip ratio is improved, which is beneficial to accurately determine the wheel state and ensure the efficiency of the motor through the control algorithm, and can improve the power and economy of the vehicle.

[0009] During the process of the motor starting to pull the vehicle forward after the throttle pedal is stepped on, the specific method of calculating the total torque of the vehicle and how to allocate the target torque to each motor is as follows:

[0010] If the first condition of traction torque allocation is met, i.e. the slip ratios of the wheels of the front and rear drive axles exceed the threshold value, the current motor controller feedback torque is reduced by a step as the new target torque of the motor, until the slip ratio is reduced to within the threshold value (optimal interval).

[0011] If the second condition of traction torque allocation is met, i.e. the slip ratio of the wheels of one of the drive axles exceeds the threshold value, the feedback torque of the motor of the drive axle is reduced by a step as the new target torque of the motor, until the slip ratio is reduced to within the threshold value (optimal interval). For the other drive axle, in order to ensure the power performance of the vehicle, the maximum allowable power P max of the power system is multiplied by the throttle pedal travel percentage to calculate the target torque of the vehicle, and the result of subtracting the target torque of the motor of the other axle (the motor exceeding the threshold value) from the target torque of the vehicle is compared with the maximum allowable torque of the motor not exceeding the threshold value, and the smaller value is taken as the target torque of the motor of the drive axle not exceeding the threshold value.

[0012] If the third condition of traction torque allocation is met, i.e. the slip ratio of the wheels of one of the drive axles exceeds the threshold value. First, the maximum allowable power P max of the power system is multiplied by the throttle pedal travel percentage to calculate the target torque of the vehicle. Then, according to the slip ratio values of the front and rear axles and the size relationship, the torque allocation coefficients of the two motors are obtained to ensure that the front and rear drive axles are maintained in the optimal slip ratio range, so as to ensure the adhesion coefficient of the tire to improve the power utilization rate and reduce energy consumption.

[0013] If the vehicle is not turning, the target torque of each motor is the product of the target torque of the whole vehicle and the torque distribution coefficient of the motor. If the vehicle is turning, the correction value of the torque distribution coefficient is obtained according to the angle of the axle relative to the vehicle body, and the correction value is higher when the angle is larger, so that the correction of the distribution coefficient increases the lateral force and reduces the lateral friction of the tire during turning.

[0014] In some technical solutions, one axle of the vehicle is both steered and driven, and the other axle is only driven. In this case, only the driving axle that can be steered provides the lateral force in the same direction as the lateral displacement of the vehicle, so the method is generally as follows: the torque distribution coefficient of the driving axle that is both steered and driven is increased by a correction value, and the torque distribution coefficient of the driving axle that is only driven is reduced by a correction value, so that the torque of the steering axle is increased and the torque of the non-steering axle is reduced, thereby increasing the lateral force.

[0015] In some technical solutions, all driving axles can be turned. In this case, the correction value of each axle is obtained according to the size and relationship of the turning angle of each axle relative to the vehicle body. For an electronic guide rubber-tyred vehicle using full-axle steering technology, the vehicle is a multi-module articulated vehicle. Since it has multiple vehicle bodies, the yaw angle of each vehicle body during turning and the turning angle of each axle relative to the vehicle body are different. Therefore, the correction value of the torque distribution coefficient of each driving axle is obtained according to the size of the angle of the articulated disc and the size of the turning angle of each driving axle relative to the vehicle body. The front axle torque distribution coefficient is increased by the correction value, and the rear axle torque coefficient is reduced by the correction value. The target torque of each motor is obtained by multiplying the target torque of the whole vehicle by the corrected torque distribution coefficient of the motor.

[0016] Preferably, during the process of braking the vehicle by stepping on the brake pedal and recovering energy by the motor, the torque distribution method is as follows:

[0017] First, the state of the vehicle is confirmed. If the ABS is in the active state, the motor is prohibited from recovering energy, and the vehicle is stopped only by mechanical braking.

[0018] When the ABS is not activated, in order to ensure the consistency of the brake pedal stroke and the deceleration during braking as much as possible, first, the size of the deceleration is calculated according to the brake pedal stroke, and the corresponding whole vehicle reverse torque of the deceleration is obtained by the table lookup method (which has been used in the industry). If the total maximum reverse torque currently available by the motor is higher than the total target reverse torque, the target reverse torque of each motor is distributed according to the proportional coefficient of the maximum reverse torque that can be provided by the single motor in the total maximum reverse torque. If the total maximum reverse torque currently available by the motor is lower than the total target torque, the maximum reverse torque of the motor is the target reverse torque of the motor. At this time, since the electric brake cannot provide the deceleration corresponding to the brake pedal stroke, the brake system will provide the total deceleration matching the brake pedal stroke by supplementing the corresponding mechanical braking.

[0019] Preferably, the method further comprises calculating a current control torque M sent to the motor controller by a fuzzy PID algorithm designed by the motor external characteristic curve, the battery characteristic and the slip rate, so that the control torque reaches the target torque in a gradual stable manner. ctrl The design of the fuzzy algorithm enables the motor feedback torque to quickly respond to the change of the accelerator pedal to ensure the power performance of the vehicle, and to avoid or reduce the possible overshoot, oscillation and impact caused by system delay and other factors, thereby improving the comfort and maneuverability of the vehicle.

[0020] Preferably, the method further comprises, when receiving a speed limit value sent by the intelligent driving system or the steering system, if the vehicle speed exceeds the speed limit value, applying a reverse torque to slow down the vehicle through electric braking and recover energy, and reducing the target torque and the control torque of the vehicle to reduce the vehicle speed to the speed limit value.

[0021] The application also provides a vehicle torque distribution device for implementing the vehicle torque distribution control method.

[0022] The data acquisition module is configured to acquire current vehicle subsystem state information.

[0023] The state machine module is configured to determine the state of the power system according to the state information acquired by the data acquisition module, and to calculate the wheel speed and the drive axle wheel slip rate.

[0024] The decision module is configured to calculate the target torque required by the motor according to the corresponding target torque algorithm of the current state.

[0025] The output module is configured to process the target torque into a control torque actually sent to the motor controller.

[0026] The application also provides a vehicle comprising the vehicle torque distribution device or controlled by the vehicle torque distribution control method.

[0027] The application also provides an electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the vehicle torque distribution control method when executing the computer program.

[0028] The application also provides a non-transitory computer readable storage medium having a computer program stored thereon, wherein the computer program is executed by a processor to implement the vehicle torque distribution control method.

[0029] Compared with the related art, the application has the following beneficial effects:

[0030] The present application sets three types of conditions for distributing the torque of the motor, and takes the steering of the vehicle as a reference condition, and adjusts the distribution ratio of the front and rear motors in real time according to the yaw angle when the vehicle body is steered, so as to reduce the friction force on the tire and reduce the impact on the hinge, thereby improving the overall performance of the centralized driving dual-motor vehicle, and is especially suitable for multi-module articulated vehicles using dual-motor centralized driving.

[0031] Secondly, when the vehicle is turning, the torque distribution relationship of the front and rear motors is controlled to make the tire slip rate in an optimal range while ensuring sufficient traction power and lateral force, and is especially suitable for multi-module articulated vehicles.

[0032] Thirdly, the same deceleration is obtained by the driver stepping the same brake pedal stroke as far as possible under different working conditions, which improves the controllability and safety of the vehicle, and can also increase the cruising range and improve the economy through energy recovery.

[0033] Fourthly, the fuzzy PID control algorithm is used to control the change rate of the actual torque of the motor, so as to obtain more accurate vehicle related data, improve the comfort and driving stability of the vehicle while ensuring the power performance. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 The traction process torque distribution strategy flowchart in the vehicle torque distribution control method provided by the present application is shown in the figure.

[0035] Figure 2 The braking process control strategy flowchart in the vehicle torque distribution control method provided by the present application is shown in the figure.

[0036] Figure 3 The structure block diagram of the vehicle torque distribution device provided by the present application is shown in the figure.

[0037] Figure 4 The structure diagram of the vehicle provided by the present application is shown in the figure.

[0038] Figure 5 The structure block diagram of the electronic device provided by the present application is shown in the figure. DETAILED DESCRIPTION

[0039] The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. For the sake of description, if the words "up", "down", "left", "right" appear in the following text, they only mean the same direction as the up, down, left and right directions of the drawings, and do not limit the structure.

[0040] As Figure 1As shown, the vehicle torque distribution control method in the embodiment of the traction state: the longitudinal acceleration of the vehicle is obtained by the inertial navigation IMU not shown in the figure, and the vehicle position is obtained by the Beidou positioning module. Then the IMU vehicle speed is obtained by integrating the longitudinal acceleration, and the positioning vehicle speed is obtained by differentiating the positioning data. Since the IMU often has zero offset and temperature drift problems, the vehicle speed obtained by integrating the longitudinal acceleration of the IMU feedback has cumulative error. Beidou positioning has a high random accuracy error, and the vehicle speed obtained by differentiating the positioning data will amplify the error. Therefore, data fusion is performed by Kalman filtering, and then a more accurate vehicle speed is obtained.

[0041] The rotational speed n of each wheel is obtained by the wheel speed sensor of the ABS w , and the wheel speed and slip ratio of the wheel are calculated using formula (1) and formula (2) respectively:

[0042] v w = n w × 2 × pi × r / 60 (1)

[0043] S = |v-v w | / v (2)

[0044] In the formula: v w is the wheel speed, n w is the wheel rotational speed, r is the wheel radius, v is the vehicle speed, and S is the slip ratio.

[0045] The motor speed n and the feedback value of the M torque are obtained by the motor controller. The motor power P is calculated using formula (3):

[0046] P m = M × n / 9550 (3)

[0047] In the formula: P m is the motor power, n is the motor speed, and M is the motor torque.

[0048] In addition, a lookup table is established according to the motor external characteristic curve, and the maximum torque M max of the motor at the current speed is obtained by linear interpolation lookup method, and the maximum power P m，Max of the current motor is calculated using formula (3).

[0049] The current voltage of the battery pack, the maximum charge and discharge current, and the power of other electrical equipment are obtained by the battery management system to calculate the maximum charge and discharge power P bms of the power system. The maximum charge and discharge power of the motor system and the maximum power of the two motors are compared, and the smaller value is taken as the maximum allowable power P max of the power system.

[0050] The relative angle between two vehicles and the angle between the axle and the vehicle are obtained by the angle sensor of the hinged disc and the axle. The travel percentage of the accelerator pedal and the brake pedal are obtained by the instrument panel system.

[0051] Assuming that the vehicle is in the process of normal straight driving, the wheel slip ratio generally meets the third distribution condition at this time. The front axle motor speed is n f The rear axle motor speed is n r When the driver steps on the accelerator pedal by 30%, the total torque required by the vehicle can be calculated as M0=30%9550P max / (n f +n r )×2. In the actual process, the accelerator pedal is not stable at 30%. Generally, it is also reduced by filtering and other methods. The slip ratios of the front axle and the rear axle are S f and S r In one case, the front axle distribution coefficient is 0.55 and the rear axle distribution coefficient is 0.45, which can be obtained by looking up the table. The front axle is slightly higher than the rear axle to ensure that the front vehicle has a certain dragging force on the rear vehicle, and to reduce or eliminate the extrusion stress at the hinge. At this time, the difference between S f and S r is within a certain range or is less than a certain limit value obtained by looking up the table. In one case, the front axle distribution coefficient is 0.7 and the rear axle distribution coefficient is 0.3, which can be obtained by looking up the table. By reducing the rear axle torque, the rear wheel speed is reduced, and the slip ratio is reduced. At this time, S f may be less than the above-mentioned limit value, and S r may be higher than the limit value.

[0052] Assuming that the vehicle is in the process of normal steering driving, in one case, the front axle distribution coefficient is 0.65 and the rear axle distribution coefficient is 0.35, which can be obtained by looking up the table. By increasing the torque of the front axle, the lateral force of the vehicle is increased. At this time, the difference between S f and S r is within a certain range or is less than a certain limit value obtained by looking up the table, and the angle of the hinged disc and the axle indicates that the front vehicle or all vehicle compartments are on the steering curve. Similarly, there is a working condition in which the front axle distribution coefficient is 0.8 and the rear axle distribution coefficient is 0.2, which can be obtained by looking up the table. In this embodiment, the front vehicle may have completed steering and entered a straight road, and the rear vehicle is still in the steering process.

[0053] If the wheel slip rate meets the second distribution condition, the total torque M0 required by the vehicle can also be calculated according to the above method. At this time, there is no need to look up the distribution ratio, and the torque of the motor of the drive shaft whose slip rate exceeds the threshold value is first reduced to M1, and then the target torque of the motor of another drive shaft can be calculated as M2 = M0 - M1. At this time, if M2 is greater than the maximum allowable torque of the motor at the current speed, the maximum allowable torque of the motor is taken as the target torque of the motor. The slip rate is related to the properties of the road surface, the mass of the vehicle, the characteristics of the tires, etc. Generally, the slip rate threshold value range suitable for a cement road surface is about 10-30%, and the optimal slip rate is 20%. In actual application, the slip rate threshold value range used can be obtained by testing the relationship between the slip rate and the road surface adhesion coefficient.

[0054] Due to the differences in the motors, reducers, and battery packs, etc. in the power systems of different vehicle models, the response speed of the motor to the control torque is also different. In order to ensure the power performance of the vehicle and reduce the body vibration caused by the torque impact of the motor, in some embodiments, a fuzzy PID control algorithm will be used to calculate the change rate of the control torque M ctrl . Its functions are as follows: 1. In the initial stage of torque change, the error is high and the cumulative error is low, and through the fuzzy algorithm, high proportional link parameters, low differential link parameters, and low integral link parameters are obtained, which ensures the power performance while reducing the torque fluctuation caused by small amplitude fluctuations of the pedal stroke; 2. In the middle stage of torque change, the error is reduced and the cumulative error is increased, and through the fuzzy algorithm, low proportional link parameters, high differential link parameters, and high integral link parameters are obtained, which balances the influence of each link to maintain a high torque change rate and ensure the response speed of the power; 3. In the later stage of torque change, the error and the cumulative error are both reduced, and through the fuzzy algorithm, medium proportional link parameters, low differential link parameters, and high integral link parameters are obtained, so that the motor torque gradually stabilizes at the target torque, reducing the static error, overshoot, and oscillation.

[0055] In addition, accidental fluctuations of the pedal stroke will be filtered through a filter to further reduce torque fluctuations; in one embodiment, the target torque increases from 0 Nm to 500 Nm. In the initial adjustment stage, the error between the motor feedback torque and the target torque is 500 Nm, the instantaneous error is 500 Nm / s, and the cumulative error is 0. At this time, the fuzzy PID control can calculate a torque change rate of 1200 Nm / s which is relatively high. In the middle adjustment stage, the instantaneous error is reduced and the cumulative error is increased. At this time, the torque change rate can also be calculated as 1200 Nm / s which is relatively high. In the later adjustment stage, the instantaneous error and the cumulative error are both gradually reduced to 0, and the torque change rate is also gradually reduced to 0 Nm / s. In another possible embodiment, the target torque may, due to the driver's pedal fluctuations, randomly fluctuate at 300 Nm with a maximum amplitude of 20 Nm. At this time, the error and the cumulative error are relatively low but not 0, and the torque change rate may be calculated as 10 Nm / s or lower. In this embodiment, although the target torque fluctuates, the algorithm will reduce the fluctuations of the actual motor torque.

[0056] like Figure 2 As shown in FIG, an embodiment of the vehicle torque distribution control method in a braking state: the vehicle is in the braking process and the ABS is not activated. The driver's brake pedal is depressed 50% of the time, and the vehicle's maximum deceleration is set to -5 m / s. 2 , it can be calculated that the deceleration corresponding to the full release of the brake pedal at this time should be -2.5m / s 2 . At this time, it can be found in the table that the required reverse torque may be 1200Nm, and the maximum reverse torque that can be provided by the front and rear axle motors is 900Nm for the front axle and 600Nm for the rear axle, respectively. The total of 1500Nm is higher than the total reverse torque. The distribution ratio can be calculated to be 9:6 or 6:4, so the target reverse torque of the front axle motor is 720Nm, and the target reverse of the rear axle motor is 480Nm. When the vehicle speed is low, the motor cannot provide high reverse torque due to its low speed. At this time, the maximum reverse torque that can be provided by the front and rear axles may be 100Nm. Then the target reverse torque of the motor is 100Nm, and the air brake is supplemented to provide a matching deceleration.

[0057] like Figure 3 As shown, the present invention provides a vehicle torque distribution device comprising: a data acquisition module, a state machine module, a decision module, and an output module. The data acquisition module is configured to collect current status information of various vehicle subsystems. The state machine module determines the state of the powertrain based on the status information collected by the data acquisition module and calculates the wheel speed and drive shaft wheel slip rate in step 2. The decision module calculates the target torque required by the motor based on a target torque algorithm corresponding to the current state rotation. The output module processes the target torque into the actual control torque sent to the motor controller.

[0058] like Figure 4 As shown, a three-carriage articulated vehicle with a centralized drive dual motor has a double-end driver's cab and can travel in both directions with two locomotives. Each locomotive is equipped with a set of motors and their controller MCU, and the motor is connected to the drive shaft 110 via a reducer. Angle sensors are provided on the drive shaft 110 and the non-drive shaft 111. ABS wheel speed sensors are provided on the wheels 112. An angle sensor is installed at the articulated plate 113. In addition, each locomotive is equipped with a satellite inertial navigation combined positioning device and a BMS battery management system (not shown in the figure). All equipment can interact and communicate with the above-mentioned vehicle torque distribution device.

[0059] Steering motors or electro-hydraulic steering gears can be installed on all drive shafts and used Figure 3The steering controller STCU in the vehicle is used to realize the full-axle steering function, enhance the maneuverability and reduce the turning radius. In addition, the driven axle steering can also be controlled separately through the steering wheel mechanical torque transmission, and the non-driven axle does not rotate, in which case only an angle sensor needs to be installed on the driven axle 110 to realize the torque distribution algorithm of the present application. During normal driving, only one end of the driver's room works, so the torque distribution method mentioned in the present application is independent of the vehicle model with double driver's rooms as shown in Figure 3 and similar equipment configurations such as front and rear double motors driving the vehicle at the same time can use this method.

[0060] The vehicle torque distribution control method provided by the present application can be executed in a programmable logic controller PLC, a printed circuit board PCB, and a computer terminal or similar electronic equipment (as shown in Figure 5 The electronic equipment includes a power supply and at least one processor, which includes but is not limited to a microprocessor MCU or a programmable logic device FPGA, at least one memory, and one or more storage media storing an operating system and an application program. The storage medium can also permanently store part of the data to prevent data loss after power failure. At least one external bus interface is used for communication, including but not limited to CAN bus, MVB bus, EtherCAT bus, and Profibus bus. The electronic equipment can also be inserted into an external storage medium including but not limited to an SD card, a TF card, a USB flash disk, and a mobile hard disk, etc. for permanently storing data recorded during program execution to facilitate subsequent analysis of data and fault causes. In some cases, the electronic equipment can directly collect sensor data or directly drive related actuators through the reserved input and output interfaces.

[0061] The present application is applicable to centralized driving double-motor articulated vehicles. For non-articulated vehicles that do not need to consider the relationship between multiple carriages during steering and the relationship between the carriages and the articulated disc, such as vehicles also equipped with double drive shafts and double motors, the method can also be used. The method includes: obtaining accurate vehicle speed and wheel speed through data fusion and filters, and calculating the slip rate of the drive shaft wheels based on the speed. The maximum power of the power system, the throttle pedal stroke, the angle of each axle, and the angle of the articulated disc are obtained, and the target torque of the front and rear motors is calculated in combination with the size relationship of the wheel slip rate. In addition, the motor is allowed to provide a counter-torque to recover energy when braking, and to ensure the consistency of the vehicle deceleration corresponding to the same brake pedal stroke percentage. According to the characteristics of the motor and the battery pack, a fuzzy PID control algorithm is designed to control the change rate of the actual control torque of the motor, thereby improving the maneuverability and comfort of the vehicle.

[0062] The above merely illustrates the embodiments of the present application, and is not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process conversion, or direct or indirect application in other related technical fields, which is made according to the content of the present application, shall be included in the patent protection scope of the present application.

Claims

1. A vehicle torque distribution control method, characterized in that: include: Step 1: Start the vehicle and collect data from relevant vehicle subsystems; Step 2: Calculate the wheel speed and the drive shaft wheel slip rate; Step 3: When the accelerator pedal is depressed and the motors are pulling the vehicle forward, the total vehicle torque is calculated and the distribution conditions satisfied are determined, and the target torque sent to each motor is distributed according to the distribution conditions. Step 3.1: If the allocation condition is that the slip ratios of the front and rear drive axle wheels both exceed the threshold, the current motor controller feedback torque is reduced by a step size as the new target torque of the motor until the slip ratio is reduced to within the threshold; or, Step 3.2: If the allocation condition is that the wheel slip rate of any drive axle exceeds the threshold, the motor feedback torque of the drive axle exceeding the threshold is reduced in steps as the new target torque of the motor until the slip rate is reduced to within the threshold; then the new target torque of the drive axle that does not exceed the threshold is calculated based on the vehicle target torque, the maximum torque allowed by the motor on the drive axle, and the new allocated target torque of the motor exceeding the threshold; or In step 3.3, if the distribution condition is that the slip rate of the front and rear drive axle wheels does not exceed the threshold, first calculate the target torque of the vehicle, and then obtain the torque distribution coefficient based on the slip rate of the front and rear drive axle wheels. If the vehicle is not turning, multiply the target torque of the vehicle by the torque distribution coefficient of the motor to obtain the target torque of each motor. If the vehicle is turning, first obtain the correction value, correct the torque distribution coefficient, and then multiply the target torque of the vehicle by the corrected torque distribution coefficient to obtain the target torque of each motor.

2. The vehicle torque distribution control method according to claim 1, characterized in that: Step three also includes calculating the maximum torque at the current speed of the motor and the maximum allowable power of the power system; in step 3.2, the target torque of the drive shaft motor that does not exceed the threshold is calculated as follows: the maximum allowable power of the power system is multiplied by the percentage of the accelerator pedal travel to calculate the target torque of the whole vehicle, and then the target torque of the motor that exceeds the threshold is subtracted from the target torque of the whole vehicle, and the calculated result is compared with the maximum allowable torque of the drive shaft motor that does not exceed the threshold, and the smaller value is taken as the new target torque of the drive shaft motor.

3. The vehicle torque distribution control method according to claim 1, characterized in that: Step three also includes calculating the maximum torque at the current motor speed and the maximum allowable power of the power system. In step 3.3, the target torque of the vehicle is calculated by multiplying the maximum allowable power of the power system by the percentage of accelerator pedal travel.

4. The vehicle torque distribution control method according to claim 3, characterized in that: In step 3, if the vehicle is in the process of turning, the correction value of the torque distribution coefficient will be obtained by looking up the table according to the angle of the axle relative to the vehicle body. The larger the angle, the higher the correction value. If one of the drive shafts is turning and driving at the same time, its torque distribution coefficient is increased by the correction value; if the other drive shaft is driving, its torque distribution coefficient is reduced by the correction value; In step 3, if all drive shafts are turned and driven simultaneously, respective correction values ​​are obtained according to the magnitude and relationship of the turning angle of each drive shaft relative to the vehicle body.

5. The vehicle torque distribution control method according to claim 1, characterized in that: The method also includes step 4, in which when the brake pedal is depressed and the motor brakes the vehicle and recovers energy, the torque distribution method is as follows: Step 4.1, confirm the vehicle status; Step 4.2: Calculate the vehicle deceleration based on the brake pedal travel percentage and obtain the vehicle reverse torque corresponding to the deceleration. In step 4.3, if the total maximum reverse torque of the motors is greater than the reverse torque of the vehicle, the ratio of the maximum reverse torque of each motor to the total maximum reverse torque is used as a distribution coefficient, and the reverse torque of the vehicle is multiplied by the distribution coefficient to obtain the target reverse torque of the motors; If the total maximum reverse torque of the motor is less than the reverse torque of the vehicle, the maximum reverse torque of each motor is taken as the target reverse torque of the motor.

6. The vehicle torque distribution control method according to claim 5, characterized in that: In step 4.3, the fuzzy PID algorithm is designed through the motor external characteristic curve, battery characteristics and slip ratio to calculate the rate of change of the control torque currently sent to the motor controller, so that the control torque reaches the target torque in a progressive and stable manner.

7. A vehicle torque distribution device, used to implement the vehicle torque distribution control method according to any one of claims 1 to 6, characterized in that: include: Data acquisition module, used to collect status information of each subsystem of the current vehicle; A state machine module, configured to determine the state of the power system based on the state information collected by the data collection module; and calculate the wheel speed and drive axle wheel slip ratio; A decision module is used to calculate the target torque required by the motor according to the target torque algorithm corresponding to the current state rotation; The output module is used to process the target torque into the actual control torque sent to the motor controller.

8. A vehicle, characterized in that: It includes the vehicle torque distribution device as described in claim 7, or is controlled by the vehicle torque distribution control method as described in any one of claims 1-6.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the vehicle torque distribution control method according to any one of claims 1 to 6 is implemented. 10 . A non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program is executed by a processor to implement the vehicle torque distribution control method according to any one of claims 1 to 6 .

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