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

Abstract

The invention discloses a torque control method, device and equipment of a distributed four-wheel-drive motor and a storage medium, and relates to the technical field of vehicles, and the torque control method of the distributed four-wheel-drive motor comprises the steps that a torque distribution coefficient is calculated according to the current vehicle speed and the wheel end demand torque, and a first torque distribution coefficient is obtained; calculating a torque distribution coefficient according to the total mass of the vehicle, the current gradient and the 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 gradient, the first torque distribution coefficient and the second torque distribution coefficient. The first torque distribution coefficient and the second torque distribution coefficient are calculated according to the current vehicle speed, the wheel end demand torque, the total vehicle mass, the current gradient and the longitudinal acceleration, then the torque of the distributed four-wheel-drive motors is controlled in combination with the current gradient, and the accuracy of distributing 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 field of vehicle technology, and in particular to a torque control method, device, equipment and storage medium for a distributed four-wheel drive motor. Background Art

[0002] With the development of electric vehicles and autonomous driving technology, distributed four-wheel drive systems are also evolving. Electric drive units are used to drive each wheel separately through electric motors, which improves the flexibility and response speed of power distribution. Distributed four-wheel drive systems have significantly improved handling performance and safety compared to traditional systems, but they also face challenges in 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 achieve accurate torque distribution of the four motors in a distributed four-wheel drive system has become an urgent problem to be solved. Summary of the invention

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

[0004] To achieve the above objectives, the present application proposes a torque control method for a distributed four-wheel drive motor, the torque control method for the distributed four-wheel drive motor comprising:

[0005] Calculate the torque distribution coefficient according to the current vehicle speed and the wheel end required 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] 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.

[0008] In one embodiment, 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 includes:

[0009] According to the current vehicle speed, the wheel end required torque and the preset front axle coefficient mapping relationship, a plurality of initial front axle distribution coefficients are obtained;

[0010] Calculating the torque of each motor according to the wheel end required torque, the multiple initial front axle distribution coefficients, the first front axle left motor coefficient, and the first rear axle left motor coefficient to obtain multiple distribution torques corresponding to each motor;

[0011] A plurality of target total efficiencies are obtained according to a plurality of distributed torques corresponding to each motor, a motor speed, a wheel-end transmission efficiency, and a motor working efficiency;

[0012] Obtaining a first front axle allocation coefficient according to the initial front axle allocation coefficient corresponding to the extreme total power in the plurality of target total efficiencies;

[0013] A 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.

[0014] In one embodiment, 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 includes:

[0015] The load ratio is calculated based on the total mass of the vehicle, the current slope and the longitudinal acceleration to obtain the load ratio of the front and rear axles;

[0016] Calculating a torque distribution coefficient according to the front and rear axle load ratio and a preset calculation method to obtain a second front axle distribution coefficient;

[0017] 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.

[0018] In one 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 includes:

[0019] Comparing the current slope with a slope threshold to obtain a slope comparison result;

[0020] When the slope comparison result is that the current slope is less than the slope threshold, determining a target torque distribution coefficient 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, determining a target torque distribution coefficient 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 one 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 step further includes:

[0024] Compare the steering wheel steering angle with the steering angle threshold to obtain a steering angle comparison result;

[0025] When the steering angle comparison result is that the steering wheel steering angle is greater than the steering angle threshold, calculating a torque distribution coefficient 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 one embodiment, the calculating the torque distribution coefficient according to the steering wheel steering angle and the current vehicle speed to obtain the updated torque distribution coefficient includes:

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

[0029] Calculating the torque according to the target yaw angular velocity to obtain the front axle yaw torque and the rear axle yaw torque;

[0030] Determine and update the front axle distribution coefficient according to the front axle distribution coefficient in the target torque distribution coefficient;

[0031] 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;

[0032] An 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 one embodiment, 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 includes:

[0034] Obtaining a front axle left motor distribution coefficient and a rear axle left motor distribution coefficient in the target torque distribution coefficient;

[0035] Calculate the torque distribution coefficient 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 an updated front axle left motor coefficient;

[0036] 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 an updated rear axle left motor coefficient.

[0037] In addition, to achieve the above purpose, the present application also proposes a torque control device for a distributed four-wheel drive motor, the torque control device for the distributed four-wheel drive motor comprising:

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

[0039] The calculation module is further used to calculate the 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;

[0040] A control module is used 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.

[0041] In addition, to achieve the above-mentioned objectives, the present application also proposes a torque control device for a distributed four-wheel drive motor, the device comprising: a memory, a processor, and a computer program stored on the memory and executable on the processor, the computer program being configured to implement the steps of the torque control method for the distributed four-wheel drive motor as described above.

[0042] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by the processor, the steps of the torque control method of the distributed four-wheel drive motor as described above are implemented.

[0043] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, it implements the steps of the torque control method of the distributed four-wheel drive motor as described above.

[0044] The present application calculates the torque distribution coefficient according to the current vehicle speed and the wheel-end required torque to obtain the first torque distribution coefficient; calculates the torque distribution coefficient according to the total vehicle mass, the current slope and the longitudinal acceleration to obtain the 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 calculated respectively by 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The accompanying drawings, which are incorporated in and constitute a part of this 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 embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0047] Figure 1 A schematic diagram of a flow chart provided for the first embodiment of the torque control method of the distributed four-wheel drive motor of the present application;

[0048] Figure 2 A schematic diagram of a flow chart provided for the second embodiment of the torque control method of the distributed four-wheel drive motor of the present application;

[0049] Figure 3 This is a schematic diagram of the module structure of the torque control device of the distributed four-wheel drive motor in an embodiment of the present application;

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

[0051] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to 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 solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0054] The main solution of the embodiment of the present application is: calculate the torque distribution coefficient according to the current vehicle speed and the wheel-end required torque to obtain the first torque distribution coefficient; calculate 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; 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.

[0055] With the development of electric vehicles and autonomous driving technology, distributed four-wheel drive systems are also evolving. Electric drive units are used to drive each wheel separately through electric motors, which improves the flexibility and response speed of power distribution. Distributed four-wheel drive systems have significantly improved handling performance and safety compared to traditional systems, but they also face challenges in 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 achieve accurate torque distribution of the four motors in a distributed four-wheel drive system has become an urgent problem to be solved.

[0056] The present application calculates the torque distribution coefficient according to the current vehicle speed and the wheel-end required torque to obtain the first torque distribution coefficient; calculates the torque distribution coefficient according to the total vehicle mass, the current slope and the longitudinal acceleration to obtain the 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 calculated respectively by 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.

[0057] It should be noted that the execution subject of this embodiment may 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 torque control device of a distributed four-wheel drive motor capable of realizing the above functions, etc. The following takes the torque control device of a distributed four-wheel drive motor as an example of the execution subject to illustrate this embodiment and the following embodiments.

[0058] Based on this, the present application embodiment provides a distributed four-wheel drive motor torque control method, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the torque control method of the distributed four-wheel drive motor of the present application.

[0059] In this embodiment, the torque control method of the distributed four-wheel drive motor includes steps S10 to 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 in the distributed four-wheel drive system is mainly controlled by three distribution coefficients, including the front axle distribution coefficient r Front , front axle left motor distribution coefficient r LF , 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] Where T LF 、T RF 、T LR 、T RR are the left front, right front, left rear, and right rear motor torques respectively, i LF 、i RF 、i LR 、i RR They are the speed ratios from the left front, right front, left rear and right rear motor to the wheel ends respectively.

[0067] It can be understood that the current vehicle speed refers to the current vehicle driving speed, the wheel-end required torque refers to the driving torque required for each wheel during the vehicle driving process, 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 the specific implementation, according to the two-dimensional calibration table, the horizontal axis is the vehicle speed and the vertical axis is the total wheel end required torque. Combined with the current vehicle speed and the driving torque required by each wheel during the vehicle driving process, the corresponding first front axle distribution coefficient is obtained. In the case of no steering and no tire slip, in order to avoid cornering force, the torque of the coaxial left and right wheels is distributed in equal proportion. The first front axle left motor distribution coefficient is equal to the first rear axle left motor distribution coefficient, that is, 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, step S10 may include steps A11 to A15:

[0070] Step A11, obtaining a plurality of initial front axle distribution coefficients according to the current vehicle speed, the wheel end required 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 pre-calibrated mapping relationship between the current vehicle speed and wheel-end required torque and the front axle distribution coefficient, and the initial front axle distribution coefficient refers to the front axle distribution coefficient during offline calculation.

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

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

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

[0075] In the specific implementation, through the formula T LF =T*r Front *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 , combined with the total required torque at the wheel end, multiple offline calculated front axle allocation coefficients, the first front axle left motor coefficient, and the first rear axle left motor coefficient, the multiple torque sizes allocated to the motors corresponding to each motor in the distributed four-wheel drive system are obtained.

[0076] Step A13, obtaining a plurality of target total efficiencies according to a plurality of allocated torques, motor speeds, wheel-end transmission efficiencies, and motor working efficiencies corresponding to the motors;

[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 speeds. The wheel-end transmission efficiency includes the transmission efficiency of the left front, right front, left rear and right rear motors output to the wheel ends. The motor working efficiency includes the working efficiency of the left front, right front, left rear and right rear motors.

[0078] In the specific implementation, since the distributed torque corresponding to each motor has multiple values, the efficiency is calculated by combining the speed of the left front, right front, left rear, and right rear motors, the transmission efficiency of the left front, right front, left rear, and right rear motors to the wheel ends, and the working efficiency of the left front, right front, left rear, and right rear motors to obtain the total efficiency of multiple distributed four-wheel drive systems.

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

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

[0081] In a specific implementation, the total efficiencies of multiple distributed four-wheel drive systems are ranked, and the total efficiency of the largest distributed four-wheel drive system is identified, and then the initial front axle distribution coefficient corresponding to the total efficiency of the largest distributed four-wheel drive system is used 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, the first front axle left motor coefficient and the first rear axle left motor coefficient corresponding to the maximum total efficiency of the distributed four-wheel drive system 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 required torque.

[0085] In the distributed four-wheel drive system, in order to avoid the generation of side forces when there is no steering and no tire slip, the torque of the coaxial left and right wheels is distributed in equal proportion, that is, r LF =0.5, r LR =0.5. A two-dimensional calibration table is established, with the horizontal axis being the vehicle speed and the vertical axis being the total wheel-end required torque, and the output being 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 required torque, the front axle distribution coefficient r is obtained offline. Front is 0 to 0.5 (interval 0.01) and r LF =0.5, r LR = 0.5 when the total system efficiency η. Corresponding to the highest total system efficiency r Front The value is used as the first front axle distribution coefficient under the vehicle speed and total wheel end required torque, and 0.5 is used as the first front axle left motor distribution coefficient and the first rear axle left motor distribution coefficient. The total system efficiency calculation formula is:

[0086] η=(T LF *n LF *η 1 +T LF *n LF *η 2 +T LF *n LF *η 3 +T LF *n LF*η 4 ) / (T LF *n LF / η LF +T RF *n RF / η RF +T LR *n LR / η LR +T RR *n RR / η RR ), where n LF 、n RF 、n LR 、n RR are the left front, right front, left rear and right rear motor speeds respectively, η 1 , η 2 , η 3 , η 4 are the transmission efficiencies from the left front, right front, left rear, and right rear motors to the wheel ends, η LF , η RF , η LR , η RR They are the working efficiency of the left front, right front, left rear and right rear motors respectively. The motor speed is calculated based on the vehicle speed, tire rolling radius and motor-to-wheel speed ratio. The transmission efficiency and working efficiency are obtained through bench testing of the electric drive system.

[0087] Step S20, calculating the 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 gross vehicle mass refers to the overall mass of the vehicle, the current slope refers to the slope of the vehicle, the longitudinal acceleration refers to the longitudinal acceleration of the vehicle when it is traveling, and the second torque distribution coefficient includes the second front axle distribution coefficient, the second front axle left motor distribution coefficient and the second rear axle left motor distribution coefficient.

[0089] In a specific implementation, the second front axle distribution coefficient is calculated based on the overall mass of the vehicle, the current slope of the vehicle, and the longitudinal acceleration of the vehicle when traveling, combined with the vehicle dynamics equation, and the second front axle left motor distribution coefficient is equal to the first front axle left motor distribution coefficient, and the second rear axle left motor distribution coefficient is equal to the first rear axle left motor distribution coefficient. Finally, the second torque distribution coefficient is obtained based on 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 may include steps A21 to A23:

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

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

[0093] In specific implementation, the proportional relationship between the vertical load (weight) borne by the front and rear axles of the vehicle and the total weight of the vehicle is obtained based on the overall mass of the vehicle, the current slope of the vehicle, and the longitudinal acceleration of the vehicle when traveling, combined with the vehicle dynamics equation.

[0094] Step A22, calculating the torque distribution coefficient according to the front and rear axle load ratio and a preset calculation method to obtain a second front axle distribution coefficient;

[0095] It can be understood that the preset calculation method refers to a preset method of calculating the torque distribution coefficient.

[0096] In a specific implementation, the second front axle distribution coefficient is calculated based on the proportional relationship between the vertical load (weight) borne by the front and rear axles of the vehicle and the total weight of the vehicle, combined with the formula: second front axle distribution coefficient = front and rear axle load ratio / (1+front and rear axle load ratio), and the second front axle distribution coefficient is obtained based on the calculation result.

[0097] Step A23, obtaining a second torque distribution coefficient 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 calculated second front axle distribution coefficient, the second front axle left motor coefficient and the second rear axle left motor coefficient are summarized to obtain the second torque distribution coefficient.

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

[0100] Step S30, 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.

[0101] It can be understood that in this embodiment, the corresponding torque distribution coefficient is selected according to the different slopes of the vehicle to distribute the motor torque of the distributed four-wheel drive system. For example: when the absolute value of the slope is less than the set slope threshold, the first torque distribution coefficient is selected to perform torque distribution control of the distributed four-wheel drive motor; conversely, when the absolute value of the slope is greater than or equal to the set slope threshold, the second torque distribution coefficient is selected to perform torque distribution control of the distributed four-wheel drive motor.

[0102] In a feasible implementation manner, step S30 may include steps A31 to A34:

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

[0104] It can be understood that the slope threshold refers to the critical slope value used to select the torque distribution coefficient, and the slope comparison result refers to the comparison result between the current slope and the slope threshold.

[0105] In a specific implementation, the current slope size of the vehicle is compared with the slope critical value used to select the torque distribution coefficient, and the result is obtained that the current slope size of the vehicle is greater than or equal to the slope critical value used to select the torque distribution coefficient, or the current slope size of the vehicle is less than the slope critical value used to select the torque distribution coefficient, that is, the size comparison result of the current slope and the slope threshold is obtained.

[0106] Step A32, when the slope comparison result is that the current slope is less than the slope threshold, 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 the torque distribution coefficient finally selected.

[0108] In a specific implementation, when the slope comparison result is that the current slope is smaller 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, 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 current slope is greater than or equal to the slope critical value used to select 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 distributed and controlled according to the torque distribution coefficient finally selected.

[0113] It should be noted that the third distribution coefficient (same as the above-mentioned 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 is ≥ the set threshold, or when the accelerator pedal opening is ≥ the set threshold and the accelerator pedal opening change rate is ≥ the set threshold, 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] This embodiment calculates the torque distribution coefficient according to the current vehicle speed and the wheel-end required torque to obtain the first torque distribution coefficient; calculates 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; 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 calculated respectively by 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 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 those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 2 After step S30, the torque control method of the distributed four-wheel drive motor further includes steps S31 to S33:

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

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

[0118] In a specific implementation, the angle change of the steering wheel relative to its initial position (usually the straight-ahead position) is compared with an angle threshold used to determine whether the steering wheel is turned, thereby obtaining a comparison result between the steering wheel steering angle and the steering angle threshold.

[0119] Step S32, when the steering angle comparison result is that the steering wheel steering angle is greater than the steering angle threshold, calculating the 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 a 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 torque distribution coefficient needs to be updated considering the steering wheel steering angle, that is, the torque distribution coefficient is calculated based on the angle change of the steering wheel relative to its initial position (usually the straight position) and the current driving speed of the vehicle to obtain an updated target torque distribution coefficient.

[0122] In a feasible implementation manner, step S32 may include steps A321 to A325:

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

[0124] It can be understood that the preset angular velocity mapping relationship refers to the pre-calibrated mapping relationship between vehicle speed and steering wheel steering angle and yaw angular velocity, and the target yaw angular velocity refers to the yaw angular velocity corresponding to the vehicle speed and steering wheel steering angle.

[0125] In a specific implementation, according to the steering wheel steering angle and the current vehicle speed, the yaw angular velocity corresponding to the vehicle speed and the steering wheel steering angle, i.e., the target yaw angular velocity, is obtained through a pre-calibrated mapping relationship between the vehicle speed, the steering wheel steering angle and the yaw angular velocity.

[0126] Step A322, calculating the torque according to the target yaw angular velocity to obtain the front axle yaw torque and the rear axle yaw torque;

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

[0128] In a specific implementation, according to the calculated vehicle speed and the yaw angular velocity corresponding to the steering wheel steering angle, the corresponding 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 calibrated mapping relationship between the yaw angular velocity and the front axle yaw torque and the rear axle yaw torque.

[0129] Step A323, determining and updating the front axle distribution coefficient according to the front axle distribution coefficient in the target torque distribution coefficient;

[0130] It can be understood that the updated front axle distribution coefficient refers to the 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 updating the front axle left motor coefficient refers to the updated front axle left motor torque distribution coefficient, and updating the rear axle left motor coefficient refers to the updated rear axle left motor torque distribution coefficient.

[0134] In a specific implementation, the torque distribution coefficient is calculated based on 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] Step A325, obtaining an updated torque distribution coefficient based on 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 manner, step A325 may include steps B3251 to B3253:

[0138] Step B3251, obtaining the front axle left motor distribution coefficient and the rear axle left motor distribution coefficient in the target torque distribution coefficient;

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

[0140] Step B3252, calculating a torque distribution coefficient 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 an 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] Step B3253, calculate the torque distribution coefficient 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: 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.

[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 the 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 an updated torque distribution coefficient according to a preset torque distribution coefficient transition rate, and the torque of the distributed four-wheel drive motor is redistributed using the updated torque distribution coefficient.

[0147] It should be noted that the fourth distribution coefficient (same as the updated torque distribution coefficient) 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 and the vertical coordinate being the steering angle of the steering wheel, 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 output being the front axle yaw torque and the rear axle yaw torque respectively; the fourth front axle distribution coefficient (same as the updated front axle distribution coefficient) = the third front axle distribution coefficient, the fourth front axle left motor distribution coefficient (same as the updated front axle left motor coefficient) = (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), the fourth rear axle left motor distribution coefficient (same as the updated rear axle left motor coefficient) = (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), and the transition rate of the distribution coefficient is controlled when the distribution coefficient is switched.

[0148] This embodiment obtains a steering angle comparison result by comparing the steering wheel steering angle with the steering angle threshold; when the steering angle comparison result is that the steering wheel steering angle is greater than the steering angle threshold, 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; according to a preset transition rate, the current torque distribution coefficient is switched to the updated torque distribution coefficient, 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, 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 distributing 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. More forms of simple transformations based on this technical concept are all within the scope of protection of the present application.

[0150] This application also provides a distributed four-wheel drive motor torque control device, please refer to Figure 3 , the torque control device of the distributed four-wheel drive motor includes:

[0151] A calculation module 10 is used to calculate a torque distribution coefficient according to the current vehicle speed and the wheel end required torque to obtain a first torque distribution coefficient;

[0152] The calculation module 10 is further used to calculate the 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;

[0153] The control module 20 is used 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.

[0154] Optionally, the calculation module 10 is further used for:

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

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

[0157] A plurality of target total efficiencies are obtained according to a plurality of distributed torques corresponding to each motor, a motor speed, a wheel-end transmission efficiency, and a motor working efficiency;

[0158] Obtaining a first front axle allocation coefficient according to the initial front axle allocation coefficient corresponding to the extreme total power in the plurality of target total efficiencies;

[0159] A 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.

[0160] Optionally, the calculation module 10 is further used for:

[0161] The load ratio is calculated based on the total mass of the vehicle, the current slope and the longitudinal acceleration to obtain the load ratio of the front and rear axles;

[0162] Calculating a torque distribution coefficient according to the front and rear axle load ratio and a preset calculation method to obtain a second front axle distribution coefficient;

[0163] 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.

[0164] Optionally, the control module 20 is further used for:

[0165] Comparing 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, determining 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, determining a target torque distribution coefficient according to the second torque distribution coefficient;

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

[0169] Optionally, the control module 20 is further used for:

[0170] Compare the steering wheel steering angle with the 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, calculating a torque distribution coefficient according to the steering wheel steering angle and the current vehicle speed to obtain an updated torque distribution coefficient;

[0172] 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.

[0173] Optionally, the control module 20 is further used for:

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

[0175] Calculating the torque according to the target yaw angular velocity to obtain the front axle yaw torque and the rear axle yaw torque;

[0176] Determine and update the front axle distribution coefficient according to the 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] An 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.

[0179] Optionally, the control module 20 is further used for:

[0180] Obtaining a front axle left motor distribution coefficient and a rear axle left motor distribution coefficient in the target torque distribution coefficient;

[0181] Calculate the torque distribution coefficient 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 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 to obtain an updated rear axle left motor coefficient.

[0183] The torque control device of the distributed four-wheel drive motor provided in the present application adopts the torque control method of the distributed four-wheel drive motor in the above-mentioned embodiment, which 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 present application are the same as the beneficial effects of the torque control method of the distributed four-wheel drive motor provided in the above-mentioned embodiment, and the other technical features in the torque control device of the distributed four-wheel drive motor are the same as the features disclosed in the above-mentioned embodiment method, which will not be repeated here.

[0184] The present application provides a torque control device for a distributed four-wheel drive motor, and the torque control device for the distributed four-wheel drive motor includes: at least one processor; and a memory communicatively connected to 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 so that the at least one processor can execute the torque control method for the distributed four-wheel drive motor in the above-mentioned embodiment one.

[0185] Reference below Figure 4 , which shows a schematic diagram of the structure of a torque control device for a distributed four-wheel drive motor suitable for implementing the embodiment of the present application. The torque control device for a distributed four-wheel drive motor in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 4 The torque control device of the distributed four-wheel drive motor shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0186] like Figure 4 As shown, the torque control device of the distributed four-wheel drive motor may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the torque control device of the distributed four-wheel drive motor are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; storage devices 1003 including, for example, a magnetic tape, a hard disk, etc.; and communication devices 1009. The communication device 1009 can allow the torque control device of the distributed four-wheel drive motor to communicate wirelessly or wired with other devices to exchange data. Although the figure shows a torque control device of a distributed four-wheel drive motor with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or provided alternatively.

[0187] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0188] The torque control device of the distributed four-wheel drive motor provided in the present application adopts the torque control method of the distributed four-wheel drive motor in the above-mentioned embodiment, which 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 present application are the same as the beneficial effects of the torque control method of the distributed four-wheel drive motor provided in the above-mentioned embodiment, and the other technical features in the torque control device of the distributed four-wheel drive motor are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0189] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0190] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0191] The present application provides a computer-readable storage medium having computer-readable program instructions (i.e., computer programs) stored thereon, and the computer-readable program instructions are used to execute the torque control method of the distributed four-wheel drive motor in the above-mentioned embodiment.

[0192] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more 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 of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0193] The above-mentioned computer-readable storage medium may be included in the torque control device of the distributed four-wheel drive motor; or it may exist independently without being assembled into the torque control device of the distributed four-wheel drive motor.

[0194] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned 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: calculates the torque distribution coefficient according to the current vehicle speed and the wheel-end required torque to obtain the first torque distribution coefficient; calculates 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; 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.

[0195] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may 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 may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0196] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0197] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0198] The readable storage medium provided in this application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned distributed four-wheel drive motor torque control method, 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 computer-readable storage medium provided in this application are the same as the beneficial effects of the distributed four-wheel drive motor torque control method provided in the above-mentioned embodiment, and will not be repeated here.

[0199] The present application also provides a computer program product, including 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 in this 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 beneficial effects of the computer program product provided in this application are the same as the beneficial effects of the torque control method of the distributed four-wheel drive motor provided in the above embodiment, which will not be repeated here.

[0201] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A torque control method for a distributed four-wheel drive motor, characterized in that: The torque control method of the distributed four-wheel drive motor includes: Calculate the torque distribution coefficient according to the current vehicle speed and the wheel end required torque to obtain a first torque distribution coefficient; 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; 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 according to claim 1, characterized in that 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: According to the current vehicle speed, the wheel end required torque and the preset front axle coefficient mapping relationship, a plurality of initial front axle distribution coefficients are obtained; Calculating the torque of each motor according to the wheel end required torque, the multiple initial front axle distribution coefficients, the first front axle left motor coefficient, and the first rear axle left motor coefficient to obtain multiple distribution torques corresponding to each motor; A plurality of target total efficiencies are obtained according to a plurality of distributed torques corresponding to each motor, a motor speed, a wheel-end transmission efficiency, and a motor working efficiency; Obtaining a first front axle allocation coefficient according to the initial front axle allocation coefficient corresponding to the extreme total power in the plurality of target total efficiencies; A 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.

3. The method according to claim 1, characterized in that 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: The load ratio is calculated based on the total mass of the vehicle, the current slope and the longitudinal acceleration to obtain the load ratio of the front and rear axles; Calculating a torque distribution coefficient according to the front and rear axle load ratio and a preset calculation method to obtain a second front axle distribution coefficient; 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.

4. The method according to claim 1, characterized in that 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: Comparing the current slope with a slope threshold to obtain a slope comparison result; When the slope comparison result is that the current slope is less than the slope threshold, determining a target torque distribution coefficient 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, determining a target torque distribution coefficient 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.

5. The method according to claim 1, characterized in that 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 includes: Compare the steering wheel steering angle with the steering angle threshold 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, calculating a torque distribution coefficient 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.

6. The method according to claim 5, characterized in that The step of calculating the torque distribution coefficient according to the steering wheel steering angle and the current vehicle speed to obtain an updated torque distribution coefficient includes: Obtaining a target yaw angular velocity according to the steering wheel steering angle, the current vehicle speed and a preset angular velocity mapping relationship; Calculating the torque according to the target yaw angular velocity to obtain the front axle yaw torque and the rear axle yaw torque; Determine and update the front axle distribution coefficient according to the front axle distribution coefficient in the target torque distribution coefficient; 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; An 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.

7. The method according to claim 6, characterized in that The step of 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 includes: Obtaining a front axle left motor distribution coefficient and a rear axle left motor distribution coefficient in the target torque distribution coefficient; Calculate the torque distribution coefficient 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 an updated front axle left motor coefficient; 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 an updated rear axle left motor coefficient.

8. A torque control device for a distributed four-wheel drive motor, characterized in that: The device comprises: A calculation module, used to calculate a torque distribution coefficient according to the current vehicle speed and the wheel end required torque to obtain a first torque distribution coefficient; The calculation module is further used to calculate the 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; A control module is used 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.

9. A torque control device for a distributed four-wheel drive motor, characterized in that: The device comprises: a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the torque control method of the distributed four-wheel drive motor as described in any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the torque control method of the distributed four-wheel drive motor as described in any one of claims 1 to 7 are implemented.

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