Torque control method, device and equipment of distributed four-wheel drive motor and storage medium

Abstract

The application discloses a torque control method, device and equipment of a distributed four-wheel drive motor and a storage medium, relates to the technical field of vehicles, and comprises the following steps: calculating a torque distribution coefficient according to a current vehicle speed and a wheel end required torque to obtain a first torque distribution coefficient; calculating the torque distribution coefficient according to a total vehicle mass, a current slope and a longitudinal acceleration to obtain a second torque distribution coefficient; and controlling the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient. The first torque distribution coefficient and the second torque distribution coefficient are respectively calculated through the current vehicle speed, the wheel end required torque, the total vehicle mass, the current slope and the longitudinal acceleration, and then the torque of the distributed four-wheel drive motor is controlled in combination with the current slope, so that the accuracy of the torque of the four motors in the distributed four-wheel drive system is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to a torque control method, device and equipment of distributed four-wheel drive motor and a storage medium. BACKGROUND

[0002] With the development of electric vehicles and autonomous driving technology, distributed four-wheel drive systems are also evolving, using electric drive units to drive each wheel through electric motors, improving the flexibility and response speed of power distribution. Distributed four-wheel drive systems have significantly improved in handling performance and safety compared to traditional systems, but also face challenges in cost and complexity. Developing more efficient and reliable distributed four-wheel drive systems will be an important research direction in the field of automotive engineering. Therefore, how to accurately distribute the torque of the four electric motors of the distributed four-wheel drive system has become a problem to be solved. SUMMARY

[0003] The main purpose of the present application is to provide a torque control method, device and equipment of distributed four-wheel drive motor and a storage medium, aiming to solve the technical problem of how to accurately distribute the torque of the four electric motors of the distributed four-wheel drive system.

[0004] To achieve the above purpose, the present application provides a torque control method of distributed four-wheel drive motor, which comprises:

[0005] calculating a torque distribution coefficient according to the current vehicle speed and the wheel end demand torque to obtain a first torque distribution coefficient;

[0006] calculating a torque distribution coefficient according to the total mass of the vehicle, the current slope and the longitudinal acceleration to obtain a second torque distribution coefficient;

[0007] controlling the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient.

[0008] In an embodiment, the step of calculating a torque distribution coefficient according to the current vehicle speed and the wheel end demand torque to obtain a first torque distribution coefficient comprises:

[0009] obtaining a plurality of initial front axle distribution coefficients according to the current vehicle speed, the wheel end demand torque and a preset front axle coefficient mapping relationship;

[0010] calculating the torque of each electric motor according to the wheel end demand torque, a plurality of initial front axle distribution coefficients, a first front axle left motor coefficient and a first rear axle left motor coefficient to obtain a plurality of distribution torques corresponding to each electric motor;

[0011] According to the multiple distribution torques corresponding to the multiple motors, motor speeds, wheel end transmission efficiencies, and motor working efficiencies, multiple target total efficiencies are obtained;

[0012] According to an initial front axle distribution coefficient corresponding to an extreme total power in the multiple target total efficiencies, a first front axle distribution coefficient is obtained;

[0013] According to the first front axle distribution coefficient, the first front axle left motor coefficient, and the first rear axle left motor coefficient, a first torque distribution coefficient is obtained.

[0014] In an embodiment, the step of calculating a torque distribution coefficient according to the total mass of the vehicle, the current slope, and the longitudinal acceleration to obtain a second torque distribution coefficient comprises:

[0015] According to the total mass of the vehicle, the current slope, and the longitudinal acceleration, a load ratio is calculated to obtain a front-rear axle load ratio;

[0016] According to the front-rear axle load ratio and a pre-designed calculation method, a torque distribution coefficient is calculated to obtain a second front axle distribution coefficient;

[0017] According to the second front axle distribution coefficient, the second front axle left motor coefficient, and the second rear axle left motor coefficient, a second torque distribution coefficient is obtained.

[0018] In an embodiment, the step of controlling the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient, and the second torque distribution coefficient comprises:

[0019] The current slope is compared with a slope threshold value to obtain a slope comparison result;

[0020] When the slope comparison result is that the current slope is less than the slope threshold value, a target torque distribution coefficient is determined according to the first torque distribution coefficient;

[0021] When the slope comparison result is that the current slope is greater than or equal to the slope threshold value, a target torque distribution coefficient is determined according to the second torque distribution coefficient;

[0022] The torque of the distributed four-wheel drive motor is controlled according to the target torque distribution coefficient.

[0023] In an embodiment, after the step of controlling the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient, and the second torque distribution coefficient, the method further comprises:

[0024] The steering wheel steering angle is compared with a steering angle threshold value to obtain a steering angle comparison result;

[0025] When the comparison result of the steering angle is that the steering wheel steering angle is greater than the steering angle threshold, a torque distribution coefficient is calculated according to the steering wheel steering angle and the current vehicle speed, to obtain an updated torque distribution coefficient;

[0026] The current torque distribution coefficient is switched to the updated torque distribution coefficient according to a preset transition rate, and the torque of the distributed four-wheel drive motor is updated according to the updated torque distribution coefficient.

[0027] In an embodiment, the calculation of the torque distribution coefficient according to the steering wheel steering angle and the current vehicle speed to obtain the updated torque distribution coefficient comprises:

[0028] The target yaw rate is obtained according to the steering wheel steering angle, the current vehicle speed, and a preset angular velocity mapping relationship;

[0029] The front axle yaw torque and the rear axle yaw torque are calculated according to the target yaw rate;

[0030] The updated front axle distribution coefficient is determined according to the front axle distribution coefficient in the target torque distribution coefficient;

[0031] The updated front axle left motor coefficient and the updated rear axle left motor coefficient are determined according to the front axle yaw torque, the rear axle yaw torque, and the updated front axle distribution coefficient;

[0032] The updated torque distribution coefficient is obtained according to the updated front axle distribution coefficient, the updated front axle left motor coefficient, and the updated rear axle left motor coefficient.

[0033] In an embodiment, the determination of the updated front axle left motor coefficient and the updated rear axle left motor coefficient according to the front axle yaw torque, the rear axle yaw torque, and the updated front axle distribution coefficient comprises:

[0034] The front axle left motor distribution coefficient and the rear axle left motor distribution coefficient in the target torque distribution coefficient are obtained;

[0035] The updated front axle left motor coefficient is calculated according to the wheel end required torque, the front axle left motor distribution coefficient in the target torque distribution coefficient, the front axle yaw torque, and the updated front axle distribution coefficient;

[0036] The updated rear axle left motor coefficient is calculated according to the wheel end required torque, the rear axle left motor distribution coefficient in the target torque distribution coefficient, the rear axle yaw torque, and the updated front axle distribution coefficient.

[0037] In addition, to achieve the above-mentioned purpose, the application further provides a torque control device of a distributed four-wheel drive motor, which comprises:

[0038] a calculation module, configured to calculate a torque distribution coefficient according to a current vehicle speed and a wheel end required torque, to obtain a first torque distribution coefficient;

[0039] the calculation module is further configured to calculate a torque distribution coefficient according to a total vehicle mass, a current slope and a longitudinal acceleration, to obtain a second torque distribution coefficient;

[0040] a control module, configured to control torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient.

[0041] In addition, to achieve the above object, the present application further provides a torque control device of a distributed four-wheel drive motor, which comprises a memory, a processor and a computer program stored in the memory and executable on the processor, and the computer program is configured to implement the steps of the torque control method of the distributed four-wheel drive motor.

[0042] In addition, to achieve the above object, the present application further provides a storage medium, which is a computer readable storage medium, and the storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the torque control method of the distributed four-wheel drive motor.

[0043] In addition, to achieve the above object, the present application further provides a computer program product, which comprises a computer program, and the computer program is executed by a processor to implement the steps of the torque control method of the distributed four-wheel drive motor.

[0044] The present application calculates a torque distribution coefficient according to a current vehicle speed and a wheel end required torque, to obtain a first torque distribution coefficient; calculates a torque distribution coefficient according to a total vehicle mass, a current slope and a longitudinal acceleration, to obtain a second torque distribution coefficient; and controls torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient. The first torque distribution coefficient and the second torque distribution coefficient are calculated respectively according to the current vehicle speed, the wheel end required torque, the total vehicle mass, the current slope and the longitudinal acceleration, and then the torque of the distributed four-wheel drive motor is controlled in combination with the current slope, so that the accuracy of distributing the torque of the four motors in the distributed four-wheel drive system is improved. BRIEF DESCRIPTION OF DRAWINGS

[0045] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, for those skilled in the art, the other drawings can also be obtained based on these drawings without any creative effort.

[0047] Figure 1 The flowchart provided for the torque control method of the distributed four-wheel drive motor of the present application embodiment one;

[0048] Figure 2 The flowchart provided for the torque control method of the distributed four-wheel drive motor of the present application embodiment two;

[0049] Figure 3 The module structure diagram of the torque control device of the distributed four-wheel drive motor of the present application embodiment;

[0050] Figure 4 The device structure diagram of the hardware running environment involved in the torque control method of the distributed four-wheel drive motor in the present application embodiment.

[0051] The purpose of the present application, the functional characteristics and advantages will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0052] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application, and are not used to limit the present application.

[0053] In order to better understand the technical solutions of the present application, the following will be described in detail in combination with the drawings in the specification and specific embodiments.

[0054] The main solution of the present application embodiment is: calculating the torque distribution coefficient according to the current vehicle speed and the wheel end demand torque to obtain the first torque distribution coefficient; calculating the torque distribution coefficient according to the total mass of the vehicle, the current slope and the longitudinal acceleration to obtain the second torque distribution coefficient; controlling the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient.

[0055] With the development of electric vehicles and automatic driving technology, the distributed four-wheel drive system is also evolving. The electric drive unit is used to drive each wheel through the electric motor, which improves the flexibility and reaction speed of power distribution. The distributed four-wheel drive system has significant improvement in handling performance and safety compared with the traditional system, but it also faces the challenges of cost and complexity. Developing a more efficient and reliable distributed four-wheel drive system will be an important research direction in the field of automotive engineering. Therefore, how to realize the accurate distribution of the torque of the four electric motors of the distributed four-wheel drive system has become a problem to be solved.

[0056] The application calculates a torque distribution coefficient according to the current vehicle speed and the wheel end required torque to obtain a first torque distribution coefficient; calculates a torque distribution coefficient according to the total mass of the vehicle, the current slope and the longitudinal acceleration to obtain a second torque distribution coefficient; and controls the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient. The first torque distribution coefficient and the second torque distribution coefficient are respectively calculated according to the current vehicle speed, the wheel end required torque, the total mass of the vehicle, the current slope and the longitudinal acceleration, and then the torque of the distributed four-wheel drive motor is controlled in combination with the current slope, thereby improving the accuracy of the torque distribution of the four motors in the distributed four-wheel drive system.

[0057] It should be noted that the execution subject of the embodiment can be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or a distributed four-wheel drive motor torque control device capable of realizing the above functions. The following takes the distributed four-wheel drive motor torque control device as an example to illustrate the embodiment and the following embodiments.

[0058] Based on this, the application provides a torque control method of a distributed four-wheel drive motor, which is described below with reference to Figure 1 , Figure 1 The flowchart of the first embodiment of the torque control method of the distributed four-wheel drive motor of the application is shown in the figure.

[0059] In this embodiment, the torque control method of the distributed four-wheel drive motor includes steps S10-S30:

[0060] Step S10, calculating a torque distribution coefficient according to the current vehicle speed and the wheel end required torque to obtain a first torque distribution coefficient;

[0061] It should be noted that the torque of the four motors of the distributed four-wheel drive system is mainly controlled by three distribution coefficients, including the front axle distribution coefficient r Front , the front axle left motor distribution coefficient r LF and the rear axle left motor distribution coefficient r LR .

[0062] T LF = T * r Front * r LF / i LF

[0063] T RF = T * r Front * (1-r LF ) / i RF

[0064] TLR = T * (1 - r Front ) * r LR / i LR

[0065] T RR = T * (1 - r Front ) * (1 - r LR ) / i RR

[0066] wherein T LF , T RF , T LR , T RR are front left, front right, rear left, rear right motor torque respectively, i LF , i RF , i LR , i RR are front left, front right, rear left, rear right motor to wheel end speed ratio respectively.

[0067] It can be understood that the current vehicle speed refers to the current vehicle driving speed, the wheel end demand torque refers to the driving torque required by each wheel during vehicle driving, and the first torque distribution coefficient includes the first front axle distribution coefficient, the first front axle left motor distribution coefficient, and the first rear axle left motor distribution coefficient.

[0068] In specific implementation, according to the formulated two-dimensional calibration table, the abscissa is the vehicle speed and the ordinate is the total wheel end demand torque, the corresponding first front axle distribution coefficient is obtained in combination with the current vehicle driving speed and the driving torque required by each wheel during vehicle driving, in the case of non-steering and no tire slip, to avoid generating side force, the torque of the coaxial left and right wheels is equally distributed, the first front axle left motor distribution coefficient is equal to the first rear axle left motor distribution coefficient, i.e. r LF = 0.5, r LR = 0.5, and then the first torque distribution coefficient is obtained according to the first front axle distribution coefficient, the first front axle left motor distribution coefficient, and the first rear axle left motor distribution coefficient.

[0069] In a feasible implementation, the step S10 can include steps A11-A15:

[0070] Step A11, obtaining a plurality of initial front axle distribution coefficients according to the current vehicle speed, the wheel end demand torque, and the preset front axle coefficient mapping relationship;

[0071] It can be understood that the preset front axle coefficient mapping relationship refers to the mapping relationship between the current vehicle speed and the wheel end demand torque and the front axle distribution coefficient pre-calibrated, and the initial front axle distribution coefficient refers to the front axle distribution coefficient when offline calculation.

[0072] In a specific implementation, a two-dimensional calibration table is established, with the horizontal coordinate being the vehicle speed, the vertical coordinate being the total wheel end demand torque, and the output being the first front axle distribution coefficient. At each vehicle speed and total wheel end demand torque, the initial front axle distribution coefficient is each front axle distribution coefficient in the range of 0 to 0.5 (with an interval of 0.01).

[0073] Step A12, calculating the torque of each motor according to the wheel end demand torque, the plurality of initial front axle distribution coefficients, the first front axle left motor coefficient, and the first rear axle left motor coefficient, to obtain a plurality of distribution torques corresponding to each motor.

[0074] It can be understood that the distribution torque refers to the torque size distributed to the motor.

[0075] In a specific implementation, the torque of each motor is calculated by the formula T LF = T * r Front * (1 - r LF ) / i LF , T RF = T * r Front * (1 - r LF ) / i RF , T LR = T * (1 - r Front ) * r LR / i LR , and T RR = T * (1 - r Front ) * (1 - r LR ) / i RR , in combination with the total demand torque of the wheel end, the plurality of offline calculated front axle distribution coefficients, the first front axle left motor coefficient, and the first rear axle left motor coefficient, to obtain a plurality of torque sizes distributed to each motor in the distributed four-wheel drive system.

[0076] Step A13, obtaining a plurality of target total efficiencies according to the plurality of distribution torques corresponding to each motor, the motor speeds, the wheel end transmission efficiencies, and the motor working efficiencies.

[0077] It can be understood that the target total efficiency refers to the total efficiency of the distributed four-wheel drive system, the motor speed includes the left front, right front, left rear, and right rear motor speed, the wheel end transmission efficiency includes the transmission efficiency of the left front, right front, left rear, and right rear motor output to the wheel end, and the motor working efficiency includes the working efficiency of the left front, right front, left rear, and right rear motor.

[0078] In a specific implementation, since the distribution torque corresponding to each motor has a plurality of values, in combination with the left front, right front, left rear, and right rear motor speeds, the transmission efficiency of the left front, right front, left rear, and right rear motor output to the wheel end, and the working efficiency of the left front, right front, left rear, and right rear motor, the efficiency is calculated to obtain a plurality of total efficiencies of the distributed four-wheel drive system.

[0079] Step A14, obtaining a first front axle distribution coefficient according to an initial front axle distribution coefficient corresponding to an extreme total power in the plurality of target total efficiencies;

[0080] It can be understood that the extreme total power refers to the maximum total efficiency of the distributed four-wheel drive system.

[0081] In a specific implementation, the total efficiencies of the plurality of distributed four-wheel drive systems are sorted, and the maximum total efficiency of the distributed four-wheel drive system is identified, and then the initial front axle distribution coefficient corresponding to the maximum total efficiency of the distributed four-wheel drive system is taken as the first front axle distribution coefficient.

[0082] Step A15, obtaining a first torque distribution coefficient according to the first front axle distribution coefficient, the first front axle left motor coefficient, and the first rear axle left motor coefficient.

[0083] In a specific implementation, the initial front axle distribution coefficient corresponding to the maximum total efficiency of the distributed four-wheel drive system, the first front axle left motor coefficient, and the first rear axle left motor coefficient are summarized to obtain the first torque distribution coefficient.

[0084] It should be noted that the first distribution coefficient is obtained according to the current vehicle speed and the total wheel end demand torque.

[0085] In the distributed four-wheel drive system, in the case of non-steering and no tire slip, to avoid generating side force, the torque of the coaxial left and right wheels is equally distributed, that is, r LF = 0.5, r LR = 0.5. A two-dimensional calibration table is established, the horizontal coordinate is the vehicle speed, the vertical coordinate is the total wheel end demand torque, and the output is the first front axle distribution coefficient. The first front axle distribution coefficient is obtained by offline calculation: at each vehicle speed and total wheel end demand torque, the front axle distribution coefficient r Front is calculated offline from 0 to 0.5 (interval 0.01) and r LF = 0.5, r LR = 0.5. The r Front value corresponding to the highest system total efficiency is taken as the first front axle distribution coefficient at the vehicle speed and the total wheel end demand torque, and 0.5 is taken as the first front axle left motor distribution coefficient and the first rear axle left motor distribution coefficient. The system total efficiency calculation formula is:

[0086] η = (T LF *n LF *η1 + T LF *n LF *η2 + T LF *n LF *η3 + T LF *n LF *η4) / (T LF *n LF / η LF +T RF *n RF / η RF +T LR *n LR / η LR +T RR *n RR / η RR , wherein n LF , n RF , n LR , n RR are the left front, right front, left rear, and right rear motor speeds, η1, η2, η3, η4 are the left front, right front, left rear, and right rear motor output-to-wheel-end transmission efficiencies, η LF , η RF , η LR , η RR are the left front, right front, left rear, and right rear motor working efficiencies. The motor speeds are calculated according to the vehicle speed, tire rolling radius, and motor-to-wheel-end speed ratio, and the transmission efficiencies and working efficiencies are obtained through bench testing of the electric drive system.

[0087] Step S20, calculating a torque distribution coefficient according to the total mass of the vehicle, the current slope, and the longitudinal acceleration, to obtain a second torque distribution coefficient;

[0088] It can be understood that the total mass of the vehicle refers to the overall mass of the vehicle, the current slope refers to the size of the slope where the vehicle is currently located, the longitudinal acceleration refers to the size of the longitudinal acceleration when the vehicle is driving, and the second torque distribution coefficient includes a second front axle distribution coefficient, a second front axle left motor distribution coefficient, and a second rear axle left motor distribution coefficient.

[0089] In a specific implementation, the second front axle distribution coefficient is obtained according to the overall mass of the vehicle, the size of the slope where the vehicle is currently located, and the size of the longitudinal acceleration when the vehicle is driving, in combination with the calculation of the vehicle dynamics equation, the second front axle left motor distribution coefficient is equal to the first front axle left motor distribution coefficient, the second rear axle left motor distribution coefficient is equal to the first rear axle left motor distribution coefficient, and finally the second torque distribution coefficient is obtained according to the second front axle distribution coefficient, the second front axle left motor distribution coefficient, and the second rear axle left motor distribution coefficient.

[0090] In a feasible implementation, step S20 can include steps A21-A23:

[0091] Step A21, calculating a load ratio according to the total mass of the vehicle, the current slope, and the longitudinal acceleration, to obtain a front-rear axle load ratio;

[0092] It can be understood that the front-rear axle load ratio refers to the proportional relationship between the vertical load (weight) borne by the front axle and the rear axle of the vehicle and the total weight of the vehicle.

[0093] In a specific implementation, according to the total mass of the vehicle, the size of the slope where the vehicle is currently located, and the size of the longitudinal acceleration when the vehicle is running, the proportional relationship between the vertical load (weight) borne by the front axle and the rear axle of the vehicle and the total weight of the vehicle is obtained by calculation in combination with the automobile dynamics equation.

[0094] Step A22, the torque distribution coefficient is calculated according to the front-rear axle load ratio and the pre-designed calculation method to obtain the second front axle distribution coefficient;

[0095] It can be understood that the pre-designed calculation method refers to the way of calculating the torque distribution coefficient in advance.

[0096] In a specific implementation, according to the proportional relationship between the vertical load (weight) borne by the front axle and the rear axle of the vehicle and the total weight of the vehicle obtained by calculation, the second front axle distribution coefficient is obtained by calculation in combination with the formula: second front axle distribution coefficient = front-rear axle load ratio / (1 + front-rear axle load ratio).

[0097] Step A23, the second torque distribution coefficient is obtained according to the second front axle distribution coefficient, the second front axle left motor coefficient and the second rear axle left motor coefficient.

[0098] In a specific implementation, the second torque distribution coefficient is obtained by summarizing the calculated second front axle distribution coefficient, the second front axle left motor coefficient and the second rear axle left motor coefficient.

[0099] It should be noted that the second distribution coefficient is obtained according to the vehicle weight, the current slope and the longitudinal acceleration. Based on the automobile dynamics equation, the front-rear axle load ratio is calculated, the second front axle distribution coefficient = front-rear axle load ratio / (1 + front-rear axle load ratio), and the second front axle left motor distribution coefficient and the second rear axle left motor distribution coefficient are still 0.5.

[0100] Step S30, the torque of the distributed four-wheel drive motor is controlled according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient.

[0101] It can be understood that in this embodiment, the corresponding torque distribution coefficient is selected according to the slope where the vehicle is located to distribute the motor torque of the distributed four-wheel drive system, for example: when the absolute value of the slope < the set slope threshold, the first torque distribution coefficient is selected for torque distribution control of the distributed four-wheel drive motor; otherwise, when the absolute value of the slope ≥ the set slope threshold, the second torque distribution coefficient is selected for torque distribution control of the distributed four-wheel drive motor.

[0102] In a feasible implementation, step S30 can include steps A31-A34:

[0103] Step A31, comparing the current slope with a slope threshold value to obtain a slope comparison result;

[0104] It can be understood that the slope threshold value refers to a slope critical value for selecting the torque distribution coefficient, and the slope comparison result refers to a size comparison result of the current slope and the slope threshold value.

[0105] In a specific implementation, the size of the slope in which the vehicle currently locates is compared with the slope critical value for selecting the torque distribution coefficient to obtain a result that the size of the slope in which the vehicle currently locates is greater than or equal to the slope critical value for selecting the torque distribution coefficient, or a result that the size of the slope in which the vehicle currently locates is less than the slope critical value for selecting the torque distribution coefficient, that is, a size comparison result of the current slope and the slope threshold value.

[0106] Step A32, when the slope comparison result is that the current slope is less than the slope threshold value, determining a target torque distribution coefficient according to the first torque distribution coefficient;

[0107] It can be understood that the target torque distribution coefficient refers to a finally selected torque distribution coefficient.

[0108] In a specific implementation, when the slope comparison result is that the size of the slope in which the vehicle currently locates is less than the slope critical value for selecting the torque distribution coefficient, it indicates that the first torque distribution coefficient is selected as the target torque distribution coefficient.

[0109] Step A33, when the slope comparison result is that the current slope is greater than or equal to the slope threshold value, determining a target torque distribution coefficient according to the second torque distribution coefficient;

[0110] In a specific implementation, when the slope comparison result is that the size of the slope in which the vehicle currently locates is greater than or equal to the slope critical value for selecting the torque distribution coefficient, it indicates that the second torque distribution coefficient is selected as the target torque distribution coefficient.

[0111] Step A34, controlling the torque of the distributed four-wheel drive motor according to the target torque distribution coefficient.

[0112] It can be understood that the torque of the distributed four-wheel drive motor is controlled according to the finally selected torque distribution coefficient.

[0113] It should be noted that the third distribution coefficient (same as the above target torque distribution coefficient) is determined according to the slope and the accelerator pedal opening. Initially, the third front axle distribution coefficient = the first front axle distribution coefficient; when the absolute value of the slope ≥ a set threshold value, or when the accelerator pedal opening ≥ a set threshold value and the accelerator pedal opening change rate ≥ a set threshold value, the third front axle distribution coefficient = the second front axle distribution coefficient; the third front axle left motor distribution coefficient and the third rear axle left motor distribution coefficient are still 0.5.

[0114] The embodiment calculates a torque distribution coefficient according to a current vehicle speed and a wheel end required torque to obtain a first torque distribution coefficient; calculates a torque distribution coefficient according to a total vehicle mass, a current slope and a longitudinal acceleration to obtain a second torque distribution coefficient; and controls torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient. The first torque distribution coefficient and the second torque distribution coefficient are respectively calculated according to the current vehicle speed, the wheel end required torque, the total vehicle mass, the current slope and the longitudinal acceleration, and then the torque of the distributed four-wheel drive motor is controlled in combination with the current slope, thereby improving the accuracy of distributing the torque of the four motors in the distributed four-wheel drive system.

[0115] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as the above embodiment one can refer to the above introduction, and the subsequent will not be described in detail. On this basis, please refer to Figure 2 , after step S30, the torque control method of the distributed four-wheel drive motor further includes steps S31-S33:

[0116] Step S31, compare the steering wheel steering angle with the steering angle threshold to obtain a steering angle comparison result;

[0117] It can be understood that the steering wheel steering angle refers to the angle change of the steering wheel relative to its initial position (usually the straight-ahead position), the steering angle threshold refers to the angle critical value for judging whether the steering wheel is turned, and the steering angle comparison result refers to the size comparison result of the steering wheel steering angle and the steering angle threshold.

[0118] In specific implementation, the angle change of the steering wheel relative to its initial position (usually the straight-ahead position) is compared with the angle critical value for judging whether the steering wheel is turned, and then the size comparison result of the steering wheel steering angle and the steering angle threshold is obtained.

[0119] Step S32, when the steering angle comparison result is that the steering wheel steering angle is greater than the steering angle threshold, calculate a torque distribution coefficient according to the steering wheel steering angle and the current vehicle speed to obtain an updated torque distribution coefficient;

[0120] It can be understood that the updated torque distribution coefficient refers to the updated target torque distribution coefficient.

[0121] In specific implementation, when the steering angle comparison result is that the steering wheel steering angle is greater than the steering angle threshold, it indicates that the steering wheel has been turned, and then the steering wheel steering angle needs to be considered to update the torque distribution coefficient, that is, the torque distribution coefficient is calculated according to the angle change of the steering wheel relative to its initial position (usually the straight-ahead position) and the current vehicle speed to obtain the updated target torque distribution coefficient.

[0122] In an implementable embodiment, step S32 can include steps A321-A325:

[0123] Step A321, obtaining a target yaw rate according to the steering wheel steering angle, the current vehicle speed, and a preset yaw rate mapping relationship;

[0124] It can be understood that the preset yaw rate mapping relationship refers to a mapping relationship between a preset vehicle speed and steering wheel steering angle and a yaw rate, and the target yaw rate refers to a yaw rate size corresponding to the vehicle speed and steering wheel steering angle.

[0125] In a specific implementation, according to the steering wheel steering angle size and the current vehicle speed, the yaw rate size corresponding to the vehicle speed and steering wheel steering angle, i.e., the target yaw rate, is obtained through the preset mapping relationship between the vehicle speed and steering wheel steering angle and the yaw rate.

[0126] Step A322, performing torque calculation according to the target yaw rate to obtain a front axle yaw torque and a rear axle yaw torque;

[0127] It can be understood that the front axle yaw torque refers to a lateral torque acting on the front axle of the vehicle, and the rear axle yaw torque refers to a lateral torque acting on the rear axle of the vehicle.

[0128] In a specific implementation, according to the calculated yaw rate size corresponding to the vehicle speed and steering wheel steering angle, the lateral torque acting on the front axle of the vehicle and the lateral torque acting on the rear axle of the vehicle are obtained through the mapping relationship between the yaw rate and the front axle yaw torque and the rear axle yaw torque.

[0129] Step A323, determining an updated front axle distribution coefficient according to a front axle distribution coefficient in the target torque distribution coefficient;

[0130] It can be understood that the updated front axle distribution coefficient refers to an updated front axle distribution coefficient.

[0131] In a specific implementation, the front axle distribution coefficient in the target torque distribution coefficient is obtained as the updated front axle distribution coefficient.

[0132] Step A324, determining an updated front axle left motor coefficient and an updated rear axle left motor coefficient according to the front axle yaw torque, the rear axle yaw torque, and the updated front axle distribution coefficient;

[0133] It can be understood that the updated front axle left motor coefficient refers to an updated front axle left motor torque distribution coefficient, and the updated rear axle left motor coefficient refers to an updated rear axle left motor torque distribution coefficient.

[0134] In a specific implementation, the calculation of the torque distribution coefficient is performed according to the lateral torque acting on the front axle of the vehicle, the lateral torque acting on the rear axle of the vehicle, and the updated front axle torque distribution coefficient, to obtain an updated front axle left motor torque distribution coefficient and an updated rear axle left motor torque distribution coefficient.

[0135] In step A325, the updated torque distribution coefficient is obtained according to the updated front axle distribution coefficient, the updated front axle left motor coefficient, and the updated rear axle left motor coefficient.

[0136] It can be understood that the updated front axle torque distribution coefficient, the updated front axle left motor torque distribution coefficient, and the updated rear axle left motor torque distribution coefficient are summarized to obtain the updated torque distribution coefficient.

[0137] In a feasible implementation, step A325 can include steps B3251-B3253.

[0138] In step B3251, the front axle left motor distribution coefficient and the rear axle left motor distribution coefficient in the target torque distribution coefficient are obtained.

[0139] It can be understood that the front axle left motor distribution coefficient and the rear axle left motor distribution coefficient in the target torque distribution coefficient are determined, and are used to calculate the updated rear axle left motor coefficient and the updated rear axle left motor coefficient.

[0140] In step B3252, the torque distribution coefficient is calculated according to the wheel end required torque, the front axle left motor distribution coefficient in the target torque distribution coefficient, the front axle yaw torque, and the updated front axle distribution coefficient, to obtain the updated front axle left motor coefficient.

[0141] It can be understood that the updated front axle left motor distribution coefficient=(total wheel end required torque*updated front axle distribution coefficient*third (target) front axle left motor distribution coefficient+front axle yaw torque) / (total wheel end required torque*updated front axle distribution coefficient), and the updated front axle left motor coefficient is calculated by the above formula.

[0142] In step B3253, the torque distribution coefficient is calculated according to the wheel end required torque, the rear axle left motor distribution coefficient in the target torque distribution coefficient, the rear axle yaw torque, and the updated front axle distribution coefficient, to obtain the updated rear axle left motor coefficient.

[0143] It can be understood that the updated rear axle left motor distribution coefficient=(total wheel end required torque*updated rear axle distribution coefficient*third (target) rear axle left motor distribution coefficient+rear axle yaw torque) / (total wheel end required torque*updated rear axle distribution coefficient), and the updated rear axle left motor coefficient is calculated by the above formula.

[0144] Step S33, switching the current torque distribution coefficient to the updated torque distribution coefficient according to a preset transition rate, and updating the torque of the distributed four-wheel drive motor according to the updated torque distribution coefficient.

[0145] In a specific implementation, the preset transition rate refers to a preset torque distribution coefficient transition rate, and the current torque distribution coefficient refers to a torque distribution coefficient currently applied by the vehicle.

[0146] In a specific implementation, the torque distribution coefficient currently applied by the vehicle is switched to the updated torque distribution coefficient according to the preset torque distribution coefficient transition rate, and the torque of the distributed four-wheel drive motor is redistributed through the updated torque distribution coefficient.

[0147] It should be noted that the fourth distribution coefficient (the same as the updated torque distribution coefficient described above) is determined according to the steering angle and the yaw rate. A two-dimensional calibration table is established, with the horizontal coordinate being the vehicle speed, the vertical coordinate being the steering wheel steering angle, and the output being the target yaw rate; two one-dimensional calibration tables are established, with the horizontal coordinate being the target yaw rate, and the outputs being the front axle yaw torque and the rear axle yaw torque, respectively; the fourth front axle distribution coefficient (the same as the updated front axle distribution coefficient described above) = the third front axle distribution coefficient, the fourth front axle left motor distribution coefficient (the same as the updated front axle left motor coefficient described above) = (total wheel end required torque * fourth front axle distribution coefficient * third front axle left motor distribution coefficient + front axle yaw torque) / (total wheel end required torque * fourth front axle distribution coefficient), and the fourth rear axle left motor distribution coefficient (the same as the updated rear axle left motor coefficient described above) = (total wheel end required torque * fourth rear axle distribution coefficient * third rear axle left motor distribution coefficient + rear axle yaw torque) / (total wheel end required torque * fourth rear axle distribution coefficient). The transition rate of the distribution coefficient is controlled when the distribution coefficient is switched.

[0148] In this embodiment, the steering wheel steering angle is compared with the steering angle threshold value to obtain a steering angle comparison result. When the steering angle comparison result is that the steering wheel steering angle is greater than the steering angle threshold value, the torque distribution coefficient is calculated according to the steering wheel steering angle and the current vehicle speed to obtain an updated torque distribution coefficient. The current torque distribution coefficient is switched to the updated torque distribution coefficient according to a preset transition rate, and the torque of the distributed four-wheel drive motor is updated according to the updated torque distribution coefficient. When the steering wheel steering angle is greater than the steering angle threshold value, the torque distribution coefficient is updated according to the steering wheel steering angle and the current vehicle speed, and then the torque of the distributed four-wheel drive motor is updated, thereby improving the accuracy of the torque of the four motors in the distributed four-wheel drive system.

[0149] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the torque control method of the distributed four-wheel drive motor of the present application. Further simple transformations based on this technical concept are within the scope of protection of the present application.

[0150] The application also provides a torque control device of a distributed four-wheel motor, which comprises Figure 3 , and the torque control device of the distributed four-wheel motor comprises:

[0151] a calculation module 10, configured to calculate a torque distribution coefficient according to a current vehicle speed and a wheel end required torque, to obtain a first torque distribution coefficient;

[0152] The calculation module 10 is further configured to calculate a torque distribution coefficient according to a total mass of the vehicle, a current slope and a longitudinal acceleration, to obtain a second torque distribution coefficient;

[0153] a control module 20, configured to control torque of the distributed four-wheel motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient.

[0154] Optionally, the calculation module 10 is further configured to:

[0155] obtain a plurality of initial front axle distribution coefficients according to the current vehicle speed, the wheel end required torque and a preset front axle coefficient mapping relationship;

[0156] calculate torque of each motor according to the wheel end required torque, the plurality of initial front axle distribution coefficients, a first front axle left motor coefficient and a first rear axle left motor coefficient, to obtain a plurality of distribution torques corresponding to each motor;

[0157] obtain a plurality of target total efficiencies according to the plurality of distribution torques corresponding to each motor, motor rotating speeds, wheel end transmission efficiencies and motor working efficiencies;

[0158] obtain the first front axle distribution coefficient according to an initial front axle distribution coefficient corresponding to an extreme total power in the plurality of target total efficiencies;

[0159] obtain the first torque distribution coefficient according to the first front axle distribution coefficient, the first front axle left motor coefficient and the first rear axle left motor coefficient.

[0160] Optionally, the calculation module 10 is further configured to:

[0161] calculate a load ratio according to the total mass of the vehicle, the current slope and the longitudinal acceleration, to obtain a front-rear axle load ratio;

[0162] calculate a torque distribution coefficient according to the front-rear axle load ratio and a preset calculation mode, to obtain a second front axle distribution coefficient;

[0163] obtain the second torque distribution coefficient according to the second front axle distribution coefficient, a second front axle left motor coefficient and a second rear axle left motor coefficient.

[0164] Optionally, the control module 20 is further configured to:

[0165] compare the current slope with a slope threshold to obtain a slope comparison result;

[0166] when the slope comparison result is that the current slope is less than the slope threshold, determine a target torque distribution coefficient according to the first torque distribution coefficient;

[0167] when the slope comparison result is that the current slope is greater than or equal to the slope threshold, determine a target torque distribution coefficient according to the second torque distribution coefficient;

[0168] control the torque of the distributed four-wheel drive motor according to the target torque distribution coefficient.

[0169] Optionally, the control module 20 is further configured to:

[0170] compare the steering wheel steering angle with a steering angle threshold to obtain a steering angle comparison result;

[0171] when the steering angle comparison result is that the steering wheel steering angle is greater than the steering angle threshold, calculate a torque distribution coefficient according to the steering wheel steering angle and the current vehicle speed to obtain an updated torque distribution coefficient;

[0172] switch the current torque distribution coefficient to the updated torque distribution coefficient according to a preset transition rate, and update the torque of the distributed four-wheel drive motor according to the updated torque distribution coefficient.

[0173] Optionally, the control module 20 is further configured to:

[0174] obtain a target yaw rate according to the steering wheel steering angle, the current vehicle speed, and a preset yaw rate mapping relationship;

[0175] perform torque calculation according to the target yaw rate to obtain a front axle yaw torque and a rear axle yaw torque;

[0176] determine an updated front axle distribution coefficient according to a front axle distribution coefficient in the target torque distribution coefficient;

[0177] determine an updated front axle left motor coefficient and an updated rear axle left motor coefficient according to the front axle yaw torque, the rear axle yaw torque, and the updated front axle distribution coefficient;

[0178] obtain an updated torque distribution coefficient according to the updated front axle distribution coefficient, the updated front axle left motor coefficient, and the updated rear axle left motor coefficient.

[0179] Optionally, the control module 20 is further configured to:

[0180] The front axle left motor distribution coefficient and the rear axle left motor distribution coefficient in the target torque distribution coefficient are obtained.

[0181] The torque distribution coefficient is calculated according to the wheel end required torque, the front axle left motor distribution coefficient in the target torque distribution coefficient, the front axle yaw torque and the updated front axle distribution coefficient, so as to obtain an updated front axle left motor coefficient.

[0182] The torque distribution coefficient is calculated according to the wheel end required torque, the rear axle left motor distribution coefficient in the target torque distribution coefficient, the rear axle yaw torque and the updated front axle distribution coefficient, so as to obtain an updated rear axle left motor coefficient.

[0183] The torque control device of the distributed four-wheel drive motor provided in the application adopts the torque control method of the distributed four-wheel drive motor in the above-mentioned embodiments, and can solve the technical problem of how to accurately distribute the torque of the four motors of the distributed four-wheel drive system. Compared with the prior art, the beneficial effects of the torque control device of the distributed four-wheel drive motor provided in the application are the same as those of the torque control method of the distributed four-wheel drive motor provided in the above-mentioned embodiments, and other technical features of the torque control device of the distributed four-wheel drive motor are the same as those disclosed in the above-mentioned embodiments, which will not be repeated here.

[0184] The application provides a torque control device of a distributed four-wheel drive motor, which comprises at least one processor and a memory in communication connection with the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the torque control method of the distributed four-wheel drive motor in the above-mentioned embodiment one.

[0185] Reference will now be made to the following description Figure 4 which shows a structure diagram of the torque control device of the distributed four-wheel drive motor suitable for being used to implement the embodiments of the application. The torque control device of the distributed four-wheel drive motor in the embodiments of the application can include but is not limited to mobile terminals such as mobile phones, notebook computers, digital broadcast receivers, PDAs (Personal Digital Assistant), PADs (Portable Application Description), PMPs (Portable Media Player), vehicle-mounted terminals (such as vehicle-mounted navigation terminals) and the like, and fixed terminals such as digital TVs, desktop computers and the like. Figure 4 The torque control device of the distributed four-wheel drive motor shown is only an example, and should not bring any limitation to the functions and use range of the embodiments of the application.

[0186] As Figure 4As shown, the distributed four-wheel drive motor torque control device can include a processing device 1001 (e.g., a central processing unit, a graphics processing unit, etc.) that can perform various appropriate actions and processes in accordance with a program stored in a read only memory (ROM) 1002 or a program loaded from a storage device 1003 into a random access memory (RAM) 1004. In the RAM 1004, various programs and data required for the distributed four-wheel drive motor torque control device to operate are also stored. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; the storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the distributed four-wheel drive motor torque control device to communicate with other devices wirelessly or by wire to exchange data. Although the distributed four-wheel drive motor torque control device with various systems is shown in the figure, it should be understood that all the systems shown are not required to be implemented or possessed. More or fewer systems can be alternatively implemented or possessed.

[0187] In particular, according to embodiments of the present disclosure, the processes described above with reference to the flowcharts can be implemented as a computer software program. For example, embodiments of the present disclosure include a computer program product comprising a computer program carried on a computer readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network by a communication device, or installed from the storage device 1003, or installed from the ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the methods of the embodiments of the present disclosure are performed.

[0188] The distributed four-wheel drive motor torque control device provided by the present disclosure adopts the distributed four-wheel drive motor torque control method in the above-mentioned embodiments, and can solve the technical problem of how to accurately distribute the torque of the four motors of the distributed four-wheel drive system. Compared with the prior art, the distributed four-wheel drive motor torque control device provided by the present disclosure has the same beneficial effects as the distributed four-wheel drive motor torque control method provided by the above-mentioned embodiments, and other technical features in the distributed four-wheel drive motor torque control device are the same as the features disclosed in the previous embodiment method, which will not be repeated here.

[0189] It should be understood that various aspects disclosed herein can be implemented in hardware, software, firmware, or combinations thereof, to achieve the various aspects disclosed herein. In the description above, specific terminology is used to describe particular features, configurations, materials, or characteristics. But such terminology is merely used for convenience and is not intended to limit the application.

[0190] The above description is merely illustrative of the application and is not intended to limit the scope of the application. Any modifications or equivalents of the application should be construed as falling within the scope of the application. The scope of the application is defined by the appended claims.

[0191] The application provides a computer readable storage medium having stored thereon computer readable program instructions (i.e., a computer program) for performing the torque control method of the distributed four-wheel motor in the above embodiment.

[0192] The computer readable storage medium provided by the application may, for example, be a U disk, but is not limited to an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, system, or device, or any combination thereof. More specific examples of the computer readable storage medium can include, but are not limited to, an electrical connection having one or more conductive wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present embodiment, the computer readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer readable storage medium can be transmitted in any suitable medium, including but not limited to electrical wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0193] The above computer readable storage medium can be included in the torque control device of the distributed four-wheel motor; or can exist separately and not be assembled into the torque control device of the distributed four-wheel motor.

[0194] The computer readable storage medium described above carries one or more programs, when the one or more programs are executed by the torque control device of the distributed four-wheel drive motor, the torque control device of the distributed four-wheel drive motor is caused to: calculate a torque distribution coefficient according to a current vehicle speed and a wheel end required torque, to obtain a first torque distribution coefficient; calculate the torque distribution coefficient according to a total mass of the vehicle, a current slope and a longitudinal acceleration, to obtain a second torque distribution coefficient; and control the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient.

[0195] Computer program code for carrying out operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0196] The flow diagrams and the block diagrams in the drawings are illustrations of architectures, functionalities, and operations of possible implementations of systems, methods, and computer program products according to various embodiments of present application. In this regard, each block in the flow diagrams or block diagrams can represent a module, a segment, or a portion of code, which comprises one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions noted in the blocks can occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and / or flow diagrams, and combinations thereof, can be implemented by special purpose hardware-based systems that perform the specified functions or operations, or combinations of special purpose hardware and computer instructions.

[0197] The modules involved in the embodiments of the present application can be implemented in a software manner or in a hardware manner. In some cases, the names of the modules do not constitute a limitation on the modules themselves.

[0198] The readable storage medium provided by the application is a computer readable storage medium, which stores computer readable program instructions (i.e. computer programs) for executing the torque control method of the distributed four-wheel drive motor, and can solve the technical problem of how to accurately distribute the torque of the four motors of the distributed four-wheel drive system. Compared with the prior art, the computer readable storage medium provided by the application has the same beneficial effects as the torque control method of the distributed four-wheel drive motor provided by the above-mentioned embodiments, and will not be repeated here.

[0199] The application further provides a computer program product comprising a computer program, which, when executed by a processor, implements the steps of the torque control method of the distributed four-wheel drive motor as described above.

[0200] The computer program product provided by the application can solve the technical problem of how to accurately distribute the torque of the four motors of the distributed four-wheel drive system. Compared with the prior art, the computer program product provided by the application has the same beneficial effects as the torque control method of the distributed four-wheel drive motor provided by the above-mentioned embodiments, and will not be repeated here.

[0201] The above only describes some embodiments of the application, and does not limit the patent scope of the application. Any equivalent structural transformation, direct / indirect application in other related technical fields based on the technical concept of the application, and the contents of the specification and drawings are included in the patent protection scope of the application.

Claims

1. A torque control method of a distributed four-wheel motor, characterized by, The torque control method of the distributed four-wheel drive motor comprises: A torque distribution coefficient is calculated according to a current vehicle speed and a wheel end required torque, and a first torque distribution coefficient is obtained. The step of calculating the torque distribution coefficient according to the current vehicle speed and the wheel end required torque to obtain the first torque distribution coefficient comprises: A plurality of initial front axle distribution coefficients are obtained according to the current vehicle speed, the wheel end required torque and a preset front axle coefficient mapping relationship. Torques of the electric machines are calculated according to the wheel end required torque, the plurality of initial front axle distribution coefficients, a first front axle left motor coefficient and a first rear axle left motor coefficient, and a plurality of distribution torques corresponding to the electric machines are obtained. A plurality of target total efficiencies are obtained according to the plurality of distribution torques corresponding to the electric machines, motor speeds, wheel end transmission efficiencies and motor working efficiencies. A first front axle distribution coefficient is obtained according to an initial front axle distribution coefficient corresponding to an extreme total power in the plurality of target total efficiencies. The first torque distribution coefficient is obtained according to the first front axle distribution coefficient, the first front axle left motor coefficient and the first rear axle left motor coefficient. A second torque distribution coefficient is obtained by calculating a torque distribution coefficient according to a total mass of the vehicle, a current slope and a longitudinal acceleration. The torque of the distributed four-wheel drive motor is controlled according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient.

2. The method of claim 1, wherein, The step of calculating the torque distribution coefficient according to the total mass of the vehicle, the current slope and the longitudinal acceleration to obtain the second torque distribution coefficient comprises: A front-rear axle load ratio is obtained by calculating a load ratio according to the total mass of the vehicle, the current slope and the longitudinal acceleration. A second front axle distribution coefficient is obtained by calculating a torque distribution coefficient according to the front-rear axle load ratio and a preset calculation mode. The second torque distribution coefficient is obtained according to the second front axle distribution coefficient, a second front axle left motor coefficient and a second rear axle left motor coefficient.

3. The method of claim 1, wherein, The step of controlling the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient comprises: A slope comparison result is obtained by comparing the current slope with a slope threshold value. When the slope comparison result is that the current slope is less than the slope threshold value, a target torque distribution coefficient is determined according to the first torque distribution coefficient. When the slope comparison result is that the current slope is greater than or equal to the slope threshold value, the target torque distribution coefficient is determined according to the second torque distribution coefficient. The torque of the distributed four-wheel drive motor is controlled according to the target torque distribution coefficient.

4. The method of claim 1, wherein, The step of controlling the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient further comprises: A steering angle comparison result is obtained by comparing a steering wheel steering angle with a steering angle threshold value. When the steering angle comparison result is that the steering wheel steering angle is greater than the steering angle threshold value, an updated torque distribution coefficient is obtained by calculating a torque distribution coefficient according to the steering wheel steering angle and the current vehicle speed. Switch the current torque distribution coefficient to the updated torque distribution coefficient according to a preset transition rate, and update the torque of the distributed four-wheel drive motor according to the updated torque distribution coefficient.

5. The method of claim 4, wherein, The torque distribution coefficient is calculated according to the steering wheel steering angle and the current vehicle speed to obtain an updated torque distribution coefficient, including: The target yaw rate is obtained according to the steering wheel steering angle, the current vehicle speed and a preset angular velocity mapping relationship; The front axle yaw torque and the rear axle yaw torque are obtained through torque calculation according to the target yaw rate; The updated front axle distribution coefficient is determined according to the front axle distribution coefficient in the target torque distribution coefficient; The updated front axle left motor coefficient and the updated rear axle left motor coefficient are determined according to the front axle yaw torque, the rear axle yaw torque and the updated front axle distribution coefficient; The updated torque distribution coefficient is obtained according to the updated front axle distribution coefficient, the updated front axle left motor coefficient and the updated rear axle left motor coefficient.

6. The method of claim 5, wherein, The updated front axle left motor coefficient and the updated rear axle left motor coefficient are determined according to the front axle yaw torque, the rear axle yaw torque and the updated front axle distribution coefficient, including: The front axle left motor distribution coefficient and the rear axle left motor distribution coefficient in the target torque distribution coefficient are obtained; The updated front axle left motor coefficient is calculated according to the wheel end demand torque, the front axle left motor distribution coefficient in the target torque distribution coefficient, the front axle yaw torque and the updated front axle distribution coefficient; The updated rear axle left motor coefficient is calculated according to the wheel end demand torque, the rear axle left motor distribution coefficient in the target torque distribution coefficient, the rear axle yaw torque and the updated front axle distribution coefficient.

7. A torque control device for a distributed four-wheel drive electric motor, characterized by, The device comprises: The calculation module is configured to calculate a torque distribution coefficient according to a current vehicle speed and a wheel end demand torque to obtain a first torque distribution coefficient. The calculation module is further configured to obtain a plurality of initial front axle distribution coefficients according to the current vehicle speed, the wheel end demand torque and a preset front axle coefficient mapping relationship; calculate the torque of each motor according to the wheel end demand torque, the plurality of initial front axle distribution coefficients, a first front axle left motor coefficient and a first rear axle left motor coefficient to obtain a plurality of distribution torques corresponding to each motor; obtain a plurality of target total efficiencies according to the plurality of distribution torques corresponding to each motor, motor speed, wheel end transmission efficiency and motor working efficiency; obtain the first front axle distribution coefficient according to an initial front axle distribution coefficient corresponding to an extreme total power in the plurality of target total efficiencies; and obtain the first torque distribution coefficient according to the first front axle distribution coefficient, the first front axle left motor coefficient and the first rear axle left motor coefficient. The calculation module is further configured to calculate a torque distribution coefficient according to a vehicle total mass, a current slope and a longitudinal acceleration to obtain a second torque distribution coefficient. The control module is configured to control the torque of the distributed four-wheel drive motor according to at least one of the current slope, the first torque distribution coefficient and the second torque distribution coefficient.

8. A torque control apparatus for a distributed four-wheel drive electric motor, characterized by, The device comprises a memory, a processor, and a computer program stored on the memory and executable on the processor, and the computer program is configured to implement the steps of the torque control method of the distributed four-wheel drive motor according to any one of claims 1 to 6.

9. A storage medium, characterized by The storage medium is a computer readable storage medium, and the storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the torque control method of the distributed four-wheel drive motor according to any one of claims 1 to 6.

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