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

Abstract

The invention provides a vehicle torque distribution control method and device, a vehicle, a storage medium and electronic equipment. According to the vehicle torque distribution control method, torque distribution conditions are set, a vehicle is started, and data of related subsystems of the vehicle are collected; calculating the wheel speed of the wheel and the slip rate of the wheel of the driving shaft; and when the accelerator pedal is stepped on and the motor pulls the vehicle to move forwards, the total torque of the vehicle is calculated, the satisfied distribution condition is judged, and the target torque sent to each motor is distributed according to the distribution condition. According to the method, the real-time working condition of the vehicle is comprehensively considered, distribution and output of the torque of the double motors are reasonably controlled, so that the overall performance of the centralized driving double-motor vehicle is improved, and the method is particularly suitable for a multi-module hinged vehicle adopting centralized driving of the double motors.

Description

Technical Field

[0001] The present invention relates to the field of motor control technology, and in particular to a vehicle torque distribution control method, device, vehicle, storage medium and electronic equipment, which are suitable for motor torque distribution of a centralized driven dual-motor articulated vehicle. Background Art

[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-unit articulated electronically guided rubber-wheeled vehicle has a strong prospect in the low- and medium-volume market of urban public transportation because it combines the advantages of large capacity and stable operation of rail vehicles and the convenience and flexibility of buses without tracks. This multi-unit articulated electronically guided rubber-wheeled vehicle has the characteristics of flexible marshaling and double-end driving without turning around, and usually adopts distributed drive or provides sufficient traction power.

[0003] For electric vehicles with dual motor centralized drive, 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 conditions 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 dynamically distribute the torque of the dual motors by establishing a vehicle dynamics model and combining it with real-time sensor data, such as the dual-motor torque distribution control method for rubber-tyred low-floor intelligent rail trains disclosed in patent announcement number CN105291887A. Although this method can improve vehicle performance in theory, it is often difficult to achieve ideal results in practical applications due to factors such as model errors, sensor noise, external interference, and controller real-time computing power. Summary of the invention

[0005] The purpose of the present invention is to provide a vehicle torque distribution control method, device, vehicle, storage medium and electronic device, aiming to improve the overall performance of centralized drive dual-motor vehicles by comprehensively considering the real-time working conditions of the vehicle and rationally controlling the distribution and output of dual-motor torque, and is particularly suitable for multi-module articulated vehicles using dual-motor centralized drive.

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

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

[0008] When the data accuracy provided by the vehicle-related subsystems is poor or cannot directly provide the required data, the method also includes improving the data accuracy or obtaining the required data through data processing methods such as filtering, data fusion, formula calculation, integration and differentiation. In addition to the subsystem data mentioned above, at least the drive shaft wheel slip rate, the maximum torque at the current motor speed and the maximum power of the power system must be obtained. Through data fusion and filters, the accuracy of vehicle speed and wheel speed is improved, and then the accuracy of slip rate is improved, which is conducive to accurately judging the wheel status and ensuring the motor efficiency through control algorithms, which can improve the power and economy of the vehicle.

[0009] When the accelerator pedal is depressed and the motor starts to pull the vehicle forward, the specific method for calculating the total vehicle torque and how to distribute the target torque sent to each motor is as follows:

[0010] If the first condition of traction torque distribution is met, that is, the slip rates of the front and rear drive axle wheels exceed the threshold, the current motor controller feedback torque is reduced in steps as the new target torque of the motor until the slip rate is reduced to the threshold (optimal range).

[0011] If the second condition of traction torque distribution is met, that is, the wheel slip rate of one of the drive shafts exceeds the threshold, the feedback torque of the drive shaft motor is reduced in steps as its new target torque until its slip rate is reduced to the threshold (optimal range). For the other drive shaft, in order to ensure the power performance of the vehicle, first take the maximum permissible power of the power system P max The target torque of the vehicle is calculated by multiplying the result by the percentage of the accelerator pedal travel. The result of subtracting the target torque of the other axle motor (the motor that exceeds the threshold) from the target torque of the vehicle is compared with the maximum allowable torque of the motor that does not exceed the threshold. Finally, the smaller value is taken as the target torque of the drive shaft motor that does not exceed the threshold.

[0012] If the third condition of traction torque distribution is met, that is, the slip ratio of no drive shaft exceeds the threshold, the maximum permissible power P of the power system is first taken. max The target torque of the vehicle is calculated by multiplying the result by the percentage of the accelerator pedal travel. Then, the torque distribution coefficient of the two motors is obtained according to the slip ratio values ​​and size relationship of the front and rear axles to ensure that the front and rear drive axles are maintained in the optimal slip ratio range, thereby ensuring the adhesion coefficient of the tires to improve power utilization and reduce energy consumption.

[0013] If the vehicle is not turning, the target torque of each motor is obtained by multiplying the target torque of the vehicle by the torque distribution coefficient of the motor. If the vehicle is in the process of turning, the correction value of the torque distribution coefficient will be obtained according to the angle of the axle relative to the body. The larger the angle, the higher the correction value. The distribution coefficient is corrected to increase the lateral force and reduce the lateral friction of the tire during turning.

[0014] In some technical solutions, the vehicle has one axle that is both steerable and driven, while the other axle is only driven. In this case, only the steerable drive axle provides a lateral force in the same direction as the vehicle's lateral movement. Therefore, the implementation method is usually as follows: the torque distribution coefficient of the drive axle that is both steerable and driven is increased according to the correction value, and the torque distribution coefficient of the drive axle that is only driven is reduced according to the correction value, thereby increasing the steering axle torque and reducing the non-steering axle torque, thereby increasing the lateral force.

[0015] In some technical solutions, all drive shafts can rotate. In this case, the respective correction values ​​will be obtained according to the angle and relationship of each shaft relative to the vehicle body. For electronically guided rubber-wheeled vehicles that use all-axle steering technology, the vehicle model is a multi-module articulated vehicle. Since it has multiple sections of the vehicle body, the yaw angle of each section of the vehicle body during the turning process and the angle of each shaft relative to the vehicle body are different. In this case, the correction value of the torque distribution coefficient of each drive shaft will be obtained according to the angle of the articulated plate and the angle of each drive shaft 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 vehicle by the corrected torque distribution coefficient of the motor.

[0016] Preferably, when the brake pedal is depressed and the motor brakes the vehicle and recovers energy, the torque distribution method is:

[0017] First, confirm the vehicle status. If the ABS is activated, the motor is prohibited from recovering energy and the vehicle is stopped only by mechanical braking.

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

[0019] Preferably, the method further comprises designing a fuzzy PID algorithm to calculate the control torque M currently sent to the motor controller by using the motor external characteristic curve, battery characteristics and slip ratio. ctrl The rate of change is the step length, so that the control torque reaches the target torque in a progressive and stable manner. Through the design of the fuzzy algorithm, the motor feedback torque can quickly respond to the changes in the accelerator pedal to ensure the vehicle's dynamic performance, and on the other hand, it can avoid or reduce possible overshoot, oscillation and impact caused by factors such as system delay, thereby improving the comfort and handling of the vehicle.

[0020] Preferably, the above method also includes applying reverse torque to decelerate and recover energy through electric braking 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, and at the same time reducing the vehicle speed to the speed limit value by reducing the vehicle target torque and control torque.

[0021] The present invention also provides a vehicle torque distribution device, which is used to implement the above-mentioned vehicle torque distribution control method, comprising:

[0022] Data acquisition module, used to collect status information of each subsystem of the current vehicle;

[0023] A state machine module, used to determine the state of the power system according to the state information collected by the data collection module; and calculate the wheel speed and the drive shaft wheel slip rate;

[0024] A decision module, used to calculate the target torque required by the motor according to the target torque algorithm corresponding to the current state rotation;

[0025] The output module is used to process the target torque into the actual control torque sent to the motor controller.

[0026] The present invention also provides a vehicle, comprising the above-mentioned vehicle torque distribution device, or controlled by the above-mentioned vehicle torque distribution control method.

[0027] The present invention 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 above-mentioned vehicle torque distribution control method when executing the computer program.

[0028] The present invention 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 above-mentioned vehicle torque distribution control method.

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

[0030] 1. The present invention sets three types of conditions to distribute the motor torque, and takes the vehicle steering as a reference condition. The front and rear motor distribution ratio is adjusted in real time according to the yaw angle of the vehicle body when turning to reduce the friction of the tires and the impact on the hinges, thereby improving the overall performance of the centralized drive dual-motor vehicle, and is particularly suitable for multi-module articulated vehicles using dual-motor centralized drive;

[0031] Second, when the vehicle is turning, while ensuring sufficient traction and lateral force, the torque distribution relationship between the front and rear motors is controlled to keep the tire slip rate in an optimal range, which is especially suitable for multi-module articulated vehicles;

[0032] 3. Ensure that the driver can obtain the same deceleration under different working conditions by stepping on the same brake pedal stroke, which improves the vehicle's controllability and safety, and at the same time increases the cruising range and improves economy through energy recovery;

[0033] 4. The rate of change of the actual torque of the motor is controlled through the fuzzy PID control algorithm to obtain more accurate vehicle-related data, thereby improving riding comfort and vehicle driving stability while ensuring power performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of a flow chart of a torque distribution strategy for a traction process in a vehicle torque distribution control method provided by the present invention;

[0035] Figure 2 A schematic diagram of a braking process control strategy flow in a vehicle torque distribution control method provided by the present invention;

[0036] Figure 3 A schematic structural block diagram of a vehicle torque distribution device provided by the present invention;

[0037] Figure 4 A schematic diagram of the structure of a vehicle provided by the present invention;

[0038] Figure 5 This is a schematic structural diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0039] The present invention 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 of the present invention and the features in the embodiments can be combined with each other without conflict. For the convenience of description, if the words "upper", "lower", "left" and "right" appear in the following, they only indicate that the upper, lower, left and right directions are consistent with the drawings themselves, and do not limit the structure.

[0040] like Figure 1As shown in the figure, an embodiment of the vehicle torque distribution control method in 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 differential positioning data. Since IMU often has zero bias and temperature drift problems, there is a cumulative error in the vehicle speed obtained by integrating the longitudinal acceleration fed back by the IMU. Beidou positioning has a higher random precision error, and the differential positioning data to obtain the vehicle speed will amplify the error. Therefore, data fusion is performed through Kalman filtering to obtain a more accurate vehicle speed.

[0041] The ABS wheel speed sensor obtains the speed of each wheel n w , and use formula (1) and formula (2) to calculate the wheel speed and slip rate respectively:

[0042] v w =n w ×2×pi×r / 60 (1)

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

[0044] Where: v w is the wheel speed, n w is the wheel speed, r is the wheel radius, v is the vehicle speed, and S is the slip rate.

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

[0046] P m =M×n / 9550 (3)

[0047] Where: 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 of the motor at the current speed is obtained by linear interpolation through the table lookup method. max , and use formula (3) to calculate the current maximum power P of the motor m，Max .

[0049] The battery management system obtains the current voltage of the battery pack, the maximum charge and discharge current, and the power of other electrical equipment to calculate the maximum charge and discharge power P of the power system. bms Compare the maximum charge and discharge power of the motor system with the maximum power of the two motors, and take the smaller value as the maximum allowable power P of the power system. max .

[0050] The relative angle between the two vehicles and the angle of the axle relative to the vehicle are obtained through the angle sensors of the hinge plate and the axle, and the travel percentage of the accelerator pedal and the brake pedal is obtained through the instrument panel system.

[0051] Assuming that the vehicle is in a normal straight-line driving process, the wheel slip ratio usually meets the third distribution condition. The front axle motor speed is n f The rear axle motor speed is n r , it can be calculated that when the driver presses the accelerator pedal for 30%, the total torque required by the vehicle is M0 = 30% × 9550 × P max / (n f +n r )×2. In practice, the accelerator pedal is not stable at 30%. Usually, its fluctuation is reduced by filtering and other methods. The slip rates of the front and rear axles are S f and S r In one case, the front axle distribution coefficient can be obtained from the table as 0.55, and the rear axle distribution coefficient is 0.45. The front axle is slightly higher than the rear axle to ensure that the front vehicle has a certain drag force on the rear vehicle, reducing or eliminating the extrusion stress at the hinge. At this time, S f and S r The difference between the two is within a certain range or is less than a certain limit value obtained from a table. In one case, the front axle distribution coefficient is 0.7 and the rear axle distribution coefficient is 0.3. By reducing the rear axle torque and reducing the rear wheel speed, the slip rate can be reduced. f is less than the limit mentioned above, and S r Above this limit.

[0052] Assuming that the vehicle is in a normal steering process, in one case, the front axle distribution coefficient is 0.65 and the rear axle distribution coefficient is 0.35. By increasing the torque of the front axle to increase the lateral force of the vehicle, it is possible that S f and S r The difference between the two is within a certain range or is less than a limit value obtained by looking up a table, and the front vehicle or all vehicles are in a turning curve through the angle of the articulated plate and the axle. There is also a working condition where the front axle distribution coefficient is 0.8 and the rear axle distribution coefficient is 0.2. In this embodiment, the front vehicle may have completed the turn and entered the straight road while the rear vehicle is still in the process of turning.

[0053] If the wheel slip rate meets the second distribution condition, the total torque M0 required by the whole vehicle can be calculated according to the above method. At this time, there is no need to find the distribution ratio. First, reduce the torque of the drive shaft motor whose slip rate exceeds the threshold to M1, and then calculate the target torque of the other drive shaft motor 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 properties such as the road surface, vehicle quality, and tire characteristics. Usually, the suitable slip rate threshold range for cement pavement is about 10-30%, and the optimal slip rate is 20%. In actual application, the slip rate threshold range used can be obtained by testing the relationship between the slip rate and the road adhesion coefficient.

[0054] Due to the differences in the motors, reducers, battery packs and other equipment in the power systems of different 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 motor torque impact, in some embodiments, the fuzzy PID control algorithm is used to calculate the control torque M ctrl The functions are as follows: 1. In the early stage of torque change, the error is high and the cumulative error is low. The high-proportional link parameters, low-differential link parameters and low-integral link parameters are obtained through the fuzzy algorithm to ensure the power performance while reducing the torque fluctuation caused by the small fluctuation of the pedal stroke; 2. In the middle stage of torque change, the error is reduced and the cumulative error is increased. The low-proportional link parameters, high-differential link parameters and high-integral link parameters are obtained through the fuzzy algorithm to balance the influence of each link to maintain a high torque change rate and ensure the power response speed; 3. In the late stage of torque change, both the error and the cumulative error are reduced. The medium-proportional link parameters, low-differential link parameters and high-integral link parameters are obtained through the fuzzy algorithm, so that the motor torque is gradually stabilized at the target torque, reducing static error, overshoot and oscillation.

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

[0056] like Figure 2 As shown, an embodiment of the vehicle torque distribution control method in the braking state: the vehicle is in the braking process and the ABS is not activated. The driver steps on the brake pedal for 50% and the maximum deceleration of the vehicle is set to -5m / s 2 , it can be calculated that the full deceleration corresponding to the brake pedal at this time should be -2.5m / s 2 . At this time, it can be found from the table that the required reverse torque may be 1200Nm, while the maximum reverse torques that the front and rear axle motors can provide are 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 torque 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 the front and rear axles can provide may be 100Nm. In this case, the target reverse torque of the motor is 100Nm, and air braking is supplemented to provide a matching deceleration.

[0057] like Figure 3 As shown, a vehicle torque distribution device of the present invention includes: a data acquisition module, a state machine module, a decision module and an output module, wherein the data acquisition module is used to collect the current state information of each subsystem of the vehicle. The state machine module determines the state of the power system according to the state information collected by the data acquisition module, and calculates the wheel speed and the wheel slip rate of the driving shaft in step 2. The decision module calculates 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 control torque actually sent to the motor controller.

[0058] like Figure 4 As shown, a three-unit articulated vehicle with centralized drive dual motors 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 through 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 can realize the full-axle steering function to enhance the maneuverability and reduce the turning radius. In addition, the steering of the driving shaft can be controlled separately through the mechanical torque transmission of the steering wheel, and the non-driving shaft does not rotate. In this case, only the angle sensor needs to be installed on the driving shaft 110 to realize the torque distribution algorithm of the present invention. During normal driving, only the driver's cab at one end works, so the torque distribution method mentioned in the method of the present invention is different from the torque distribution method of the present invention. Figure 3 The method is not relevant to the model with a double cab shown, and can be used for models with similar equipment configurations such as front and rear dual motors that drive the vehicle simultaneously.

[0060] The vehicle torque distribution control method provided by the present invention can be implemented in a programmable logic controller PLC, a printed circuit board PCB, a computer terminal or similar electronic equipment (such as Figure 5 As shown). The electronic device includes a power supply and at least one processor, and the processor 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 for storing operating systems and application programs. 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 device can also be inserted with external storage media including but not limited to SD card, TF card, U disk and mobile hard disk, etc., for permanent storage of data recorded during program execution to facilitate subsequent analysis of data and fault causes. In some cases, the electronic device can directly collect sensor data or directly drive related actuators through the reserved input and output interfaces.

[0061] The present invention is applicable to centrally driven dual-motor articulated vehicles. For non-articulated vehicles that do not need to consider the relationship between multiple carriages and the relationship between the carriages and the hinge plate during the steering process, if they are also equipped with dual drive shafts and dual motors, this 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 wheel. The maximum power of the power system, the accelerator pedal stroke, the rotation angle of each shaft and the hinge plate angle 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 reverse torque to recover energy during braking, and the consistency of the vehicle deceleration corresponding to the same percentage of brake pedal stroke is ensured. According to the characteristics of the motor and the battery pack, a fuzzy PID control algorithm is designed to control the rate of change of the actual control torque of the motor, thereby improving the vehicle's handling and comfort.

[0062] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A vehicle torque distribution control method, characterized in that: include: Step 1: Start the vehicle and collect data from relevant subsystems of the vehicle; Step 2, calculating the wheel speed and the wheel slip rate of the driving shaft; Step 3: when the accelerator pedal is depressed and the motor is pulling the vehicle forward, the total torque of the vehicle 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 rates 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 rate is reduced to within the threshold; or, Step 3.2, if the allocation condition is that the wheel slip rate of any drive shaft exceeds the threshold, the motor feedback torque of the drive shaft 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 on the drive shaft that does not exceed the threshold is calculated by the vehicle target torque, the maximum allowable torque of the motor on the drive shaft, and the new allocated target torque of the motor exceeding the threshold; or, 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 by multiplying the maximum allowable power of the power system by the percentage of the accelerator pedal travel to obtain the target torque of the whole vehicle, and then subtract the target torque of the motor that exceeds the threshold from the target torque of the whole vehicle, compare the calculated result with the maximum allowable torque of the drive shaft motor that does not exceed the threshold, and take the smaller value 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 speed of the motor 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 the 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 turned and driven at the same time, its torque distribution coefficient is increased by the correction value; if the other drive shaft is driven, its torque distribution coefficient is reduced by the correction value; In step three, 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 invention also includes step 4, in which when the brake pedal is pressed 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, calculating the vehicle deceleration according to the percentage of brake pedal travel, and obtaining the vehicle reverse torque corresponding to the deceleration; Step 4.3, if the total maximum reverse torque of the motor is greater than the reverse torque of the whole vehicle, the proportion of the maximum reverse torque of each motor in the total maximum reverse torque is used as the distribution coefficient, and the reverse torque of the whole vehicle is multiplied by the distribution coefficient to obtain the target reverse torque of the motor; If the total maximum reverse torque of the motor is less than the reverse torque of the whole 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 change rate 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, used to determine the state of the power system according to the state information collected by the data collection module; And calculate the wheel speed and drive shaft wheel slip rate; A decision module, 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 as described in any one of claims 1-6 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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