Torque control method and device, vehicle and readable storage medium

Abstract

The invention provides a torque control method and device, a vehicle and a readable storage medium, the method is applied to the technical field of vehicles, and the method comprises the steps that the slip rate of the vehicle is determined; under the condition that the slip rate of the vehicle is larger than the slip rate threshold value, responding to the situation that the vehicle is in the variable-speed driving state, and obtaining the rotating speed limit value of a driving motor of the vehicle, the current rotating speed of the driving motor and the current output torque of the driving motor; according to the slip rate, the rotating speed limit value and the current rotating speed of the vehicle and the current output torque of the driving motor, the target output torque of the driving motor is determined, and when the vehicle is in the accelerated driving state, the determined target output torque is smaller than the current output torque; when the vehicle is in the deceleration driving state, the determined target output torque is larger than the current output torque; and adjusting the current output torque of the driving motor to the target output torque so as to adjust the rotating speed of the driving motor. The method can prevent the vehicle from shaking and abnormal sound when the vehicle passes through the deceleration strip during acceleration / deceleration.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and more specifically, to a torque control method, device, vehicle and readable storage medium in the field of vehicle technology. Background Art

[0002] When the vehicle is driven by pure electric motors, loud noises may occur in some scenarios. For example, when the vehicle accelerates or decelerates over a speed bump, the wheels will be in the air for a short time after hitting the speed bump. Since the wheels lose adhesion to the road during the process of being in the air, the contact between the wheels and the ground is reduced instantly, so the load on the motor will be reduced instantly, and the speed of the motor will also change dramatically (rapidly increase or decrease).

[0003] However, when the motor speed changes rapidly, the meshing of the gears inside the gearbox becomes uneven, which causes impact and friction between the gears, and causes obvious vibration and abnormal noise. The obvious vibration and abnormal noise will reduce the user's driving experience. Therefore, how to avoid the vibration and abnormal noise of the vehicle when the vehicle accelerates or decelerates over the speed bump is an urgent problem to be solved. Summary of the invention

[0004] The present application provides a torque control method, a vehicle, and a readable storage medium, which can prevent the vehicle from shaking and making abnormal noises when the vehicle accelerates / decelerates over a speed bump.

[0005] In a first aspect, a torque control method is provided, the method comprising: determining a slip rate of a vehicle; when the slip rate of the vehicle is greater than a slip rate threshold, in response to the vehicle being in a speed-changing driving state, obtaining a speed limit of a drive motor of the vehicle, a current speed of the drive motor and a current output torque of the drive motor; determining a target output torque of the drive motor according to the slip rate, the speed limit, the current speed and the current output torque of the drive motor, the target output torque determined when the vehicle is in an accelerating driving state is less than the current output torque, and the target output torque determined when the vehicle is in a decelerating driving state is greater than the current output torque; and adjusting the current output torque of the drive motor to the target output torque to adjust the speed of the drive motor.

[0006] In the above technical scheme, when the slip rate of the vehicle is greater than the slip rate threshold (which can be understood as when the vehicle passes through a speed bump), in response to the vehicle being in a speed-changing driving state (which can be understood as the vehicle being in an accelerating driving state or a decelerating driving state), the speed limit of the vehicle's drive motor, the current speed of the drive motor and the current output torque of the drive motor can be obtained; and the target output torque of the drive motor can be determined based on the vehicle's slip rate, speed limit, current speed and current output torque of the drive motor; and finally the current output torque of the drive motor is adjusted to the target output torque, thereby adjusting the speed of the drive motor. Since the target output torque determined when the vehicle is in an accelerating state is less than the current output torque, and the target output torque determined when the vehicle is in a decelerating state is greater than the current output torque, when the slip rate of the vehicle is greater than the slip rate threshold and the vehicle is in an accelerating state, that is, when the speed of the drive motor increases rapidly, the current speed of the drive motor can be reduced by reducing the current output torque of the drive motor; when the slip rate of the vehicle is greater than the slip rate threshold and the vehicle is in a decelerating state, that is, when the speed of the drive motor decreases rapidly, the current speed of the drive motor can be increased by increasing the current output torque of the drive motor, thereby avoiding shaking and abnormal noise caused by a sudden change (rapid decrease or increase) in the speed of the drive motor during driving, thereby improving the user's driving experience.

[0007] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the slip rate of the vehicle includes the front wheel slip rate of the vehicle and the rear wheel slip rate of the vehicle; determining the slip rate of the vehicle includes: obtaining the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed, and the acceleration of the vehicle; determining the front wheel slip rate and the rear wheel slip rate according to the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed and the acceleration of the vehicle.

[0008] In the above technical scheme, it is taken into account that the slip rate of the vehicle may include the front wheel slip rate and the rear wheel slip rate, that is, in a possible implementation manner, the front wheel slip rate and the rear wheel slip rate of the vehicle may be determined separately, so that subsequently, when the front wheel slip rate / rear wheel slip rate of the vehicle is greater than the slip rate threshold, in response to the vehicle being in a speed-changing driving state, the current output torque of the drive motor is adjusted, thereby increasing the application scenarios for adjusting the current output torque of the drive motor.

[0009] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the front wheel slip rate and the rear wheel slip rate are determined according to the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed and the accelerator pedal opening, including: determining the average front wheel speed according to the left front wheel speed and the right front wheel speed; determining the average rear wheel speed according to the left rear wheel speed and the right rear wheel speed; when the acceleration of the vehicle is greater than the acceleration threshold, using the smaller average wheel speed of the front wheel average wheel speed and the average wheel speed of the rear wheel as the reference wheel speed; or, when the acceleration of the vehicle is less than the acceleration threshold, using the larger average wheel speed of the front wheel average wheel speed and the average wheel speed of the rear wheel as the reference wheel speed; determining the front wheel slip rate according to the reference wheel speed and the average front wheel speed; determining the rear wheel slip rate according to the reference wheel speed and the average rear wheel speed.

[0010] In the above technical solution, it should be noted that when the acceleration of the vehicle is greater than the acceleration threshold, it indicates that the vehicle is in an accelerated driving state. Since the driving wheels of the vehicle (for example, the front wheels or the rear wheels) are prone to slip when the vehicle accelerates over a speed bump, the wheel speed is significantly higher than the actual vehicle speed. In this case, in order to ensure that the determined reference wheel speed is closer to the wheel speed of the wheels without slipping, the smaller average wheel speed of the front wheel average wheel speed and the rear wheel average wheel speed can be used as the reference wheel speed, so that the determined reference wheel speed is closer to the wheel speed of the wheels without slipping, that is, closer to the actual vehicle speed. When the acceleration of the vehicle is less than the acceleration threshold, it indicates that the vehicle is in an accelerated driving state. It is clear that the vehicle is in a decelerating driving state at this time. When the vehicle decelerates and passes over a speed bump, the wheels of the vehicle are prone to slip due to excessive braking force, which causes the wheel speed to be significantly lower than the actual vehicle speed. In this case, in order to ensure that the determined reference wheel speed is closer to the wheel speed of the wheels that have not slipped, the larger average wheel speed between the front wheel average wheel speed and the rear wheel average wheel speed can be used as the reference wheel speed, so that the determined reference wheel speed is closer to the wheel speed of the wheels that have not slipped, that is, closer to the actual speed of the vehicle, thereby improving the accuracy of the wheel slip rate (rear wheel slip rate / front wheel slip rate) determined based on the reference wheel speed and the average wheel speed (rear wheel average wheel speed / front wheel average wheel speed).

[0011] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the speed limit of the drive motor includes an upper speed limit and a lower speed limit; the slip rate of the vehicle includes a front wheel slip rate of the vehicle and a rear wheel slip rate of the vehicle; when the slip rate of the vehicle is greater than a slip rate threshold, in response to the vehicle being in a speed-changing driving state, the speed limit of the drive motor of the vehicle, the current speed of the drive motor and the current output torque of the drive motor are obtained, including: when the front wheel slip rate or the rear wheel slip rate is greater than the slip rate threshold, the acceleration of the vehicle is obtained; when the acceleration of the vehicle is greater than the acceleration threshold, the upper speed limit of the drive motor, the current speed of the drive motor and the current output torque of the drive motor are obtained; or, when the acceleration of the vehicle is less than the acceleration threshold, the lower speed limit of the drive motor, the current speed of the drive motor and the current output torque of the drive motor are obtained.

[0012] In the above technical scheme, it is taken into account that the speed limit of the drive motor includes an upper speed limit and a lower speed limit, and when the slip rate of the vehicle is greater than the slip rate threshold and the acceleration of the vehicle is greater than the acceleration threshold, the speed of the drive motor will increase rapidly. At this time, the current speed of the drive motor will be greater than the upper speed limit of the drive motor. That is, in this case, it is necessary to obtain the upper speed limit of the drive motor to ensure that the target output torque that is less than the current output torque of the drive motor can be determined based on the speed difference between the current speed of the drive motor and the upper speed limit of the drive motor, so as to control the current output torque of the drive motor to be reduced to the target output torque, thereby reducing the current speed of the drive motor and avoiding the speed of the drive motor. The speed of the drive motor will increase rapidly, causing the vehicle to shake and make abnormal noises; when the slip rate of the vehicle is greater than the slip rate threshold and the acceleration of the vehicle is less than the acceleration threshold, the speed of the drive motor will decrease rapidly. At this time, the current speed of the drive motor will be less than the lower limit of the speed of the drive motor. In this case, it is necessary to obtain the lower limit of the speed of the drive motor to ensure that the target output torque greater than the current output torque of the drive motor can be determined based on the speed difference between the current speed of the drive motor and the lower limit of the speed of the drive motor, so as to control the current output torque of the drive motor to increase to the target output torque, thereby increasing the current speed of the drive motor to avoid the speed of the drive motor increasing rapidly and causing the vehicle to shake and make abnormal noises.

[0013] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the target output torque of the drive motor is determined according to the vehicle's slip rate, speed limit, current speed and current output torque of the drive motor, including: determining a correction factor corresponding to the vehicle's slip rate according to a preset relationship correspondence table; when the vehicle's acceleration is greater than an acceleration threshold, using the difference between the upper speed limit and the current speed of the drive motor as the initial speed difference; determining the target output torque of the drive motor according to the initial speed difference, the correction factor and the current output torque of the drive motor; or, when the vehicle's acceleration is less than the acceleration threshold, using the difference between the lower speed limit and the current speed of the drive motor as the initial speed difference; determining the target output torque of the drive motor according to the initial speed difference, the correction factor and the current output torque of the drive motor.

[0014] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the target output torque of the drive motor is determined based on the initial speed difference, the correction factor and the current output torque of the drive motor, including: determining the target speed difference based on the initial speed difference and the correction factor; determining the target output torque of the drive motor based on the target speed difference and the current output torque of the drive motor.

[0015] In the above technical scheme, in the process of determining the target output torque of the drive motor, the corrected speed difference, that is, the target speed difference, can be determined based on the initial speed difference and the correction factor, and then the target output torque of the drive motor can be determined based on the target speed difference and the current output torque of the drive motor, so as to ensure the accuracy of the determined target output torque of the drive motor.

[0016] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the target output torque of the drive motor is determined according to the target speed difference and the current output torque of the drive motor, including: determining a first torque adjustment value according to a preset proportional gain and the target speed difference; integrating the target speed difference based on a preset time length to obtain the cumulative speed difference of the drive motor within the preset time length; determining a second torque adjustment value according to a preset integral gain and the cumulative speed difference; differentiating the target speed difference based on a preset time step to obtain the speed difference change rate of the drive motor within the preset time step; determining a third torque adjustment value according to a preset differential gain and the speed difference change rate; determining the target torque adjustment value according to the first torque adjustment value, the second torque adjustment value and the third torque adjustment value; determining the target output torque of the drive motor according to the target torque adjustment value and the current output torque of the drive motor.

[0017] In a second aspect, a torque control device is provided, the device comprising:

[0018] A determination module, for determining a slip ratio of a vehicle;

[0019] an acquisition module, configured to acquire a speed limit value of a drive motor of the vehicle, a current speed of the drive motor, and a current output torque of the drive motor in response to the vehicle being in a speed-changing driving state when the slip rate of the vehicle is greater than a slip rate threshold;

[0020] The determination module is further used to determine the target output torque of the drive motor according to the slip rate, the speed limit, the current speed and the current output torque of the drive motor of the vehicle, wherein the target output torque determined when the vehicle is in an accelerating state is less than the current output torque, and the target output torque determined when the vehicle is in a decelerating state is greater than the current output torque;

[0021] The adjustment module is used to adjust the current output torque of the drive motor to the target output torque so as to adjust the rotation speed of the drive motor.

[0022] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, a determination module is specifically used to obtain the left front wheel speed, right front wheel speed, left rear wheel speed, right rear wheel speed, and acceleration of the vehicle; and determine the front wheel slip rate and the rear wheel slip rate based on the left front wheel speed, right front wheel speed, left rear wheel speed, right rear wheel speed and the acceleration of the vehicle.

[0023] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the determination module is specifically used to determine the average front wheel speed based on the left front wheel speed and the right front wheel speed; determine the average rear wheel speed based on the left rear wheel speed and the right rear wheel speed; when the acceleration of the vehicle is greater than the acceleration threshold, use the smaller average wheel speed of the front wheel and the average wheel speed of the rear wheel as the reference wheel speed; or, when the acceleration of the vehicle is less than the acceleration threshold, use the larger average wheel speed of the front wheel and the average wheel speed of the rear wheel as the reference wheel speed; determine the front wheel slip rate based on the reference wheel speed and the front wheel average wheel speed; determine the rear wheel slip rate based on the reference wheel speed and the rear wheel average wheel speed.

[0024] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the acquisition module is specifically used to obtain the acceleration of the vehicle when the front wheel slip rate or the rear wheel slip rate is greater than the slip rate threshold; when the acceleration of the vehicle is greater than the acceleration threshold, obtain the upper limit of the speed of the drive motor, the current speed of the drive motor and the current output torque of the drive motor; or, when the acceleration of the vehicle is less than the acceleration threshold, obtain the lower limit of the speed of the drive motor, the current speed of the drive motor and the current output torque of the drive motor.

[0025] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the determination module is specifically used to determine a correction factor corresponding to the slip rate of the vehicle according to a preset relationship correspondence table; when the acceleration of the vehicle is greater than the acceleration threshold, the difference between the upper limit of the speed of the drive motor and the current speed is used as the initial speed difference; based on the initial speed difference, the correction factor and the current output torque of the drive motor, the target output torque of the drive motor is determined; or, when the acceleration of the vehicle is less than the acceleration threshold, the difference between the lower limit of the speed of the drive motor and the current speed is used as the initial speed difference; based on the initial speed difference, the correction factor and the current output torque of the drive motor, the target output torque of the drive motor is determined.

[0026] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the determination module is specifically used to determine the target speed difference based on the initial speed difference and the correction factor; and determine the target output torque of the drive motor based on the target speed difference and the current output torque of the drive motor.

[0027] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the determination module is specifically used to determine a first torque adjustment value based on a preset proportional gain and a target speed difference; based on a preset time length, perform an integral operation on the target speed difference to obtain a cumulative speed difference of the drive motor within the preset time length; determine a second torque adjustment value based on a preset integral gain and the cumulative speed difference; based on a preset time step, perform a differential operation on the target speed difference to obtain a speed difference change rate of the drive motor within the preset time step; determine a third torque adjustment value based on a preset differential gain and a speed difference change rate; determine a target torque adjustment value based on the first torque adjustment value, the second torque adjustment value and the third torque adjustment value; determine a target output torque of the drive motor based on the target torque adjustment value and the current output torque of the drive motor.

[0028] In a third aspect, a vehicle is provided, comprising a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, so that the vehicle executes the torque control method in the first aspect or any possible implementation of the first aspect.

[0029] In a fourth aspect, a computer program product is provided, which includes: a computer program code, which, when executed on a computer, enables the computer to execute the torque control method in the first aspect or any possible implementation of the first aspect.

[0030] In a fifth aspect, a computer-readable storage medium is provided, which stores a computer program code. When the computer program code runs on a computer, the computer executes the torque control method in the above-mentioned first aspect or any possible implementation of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of an implementation environment of a torque control method provided in an embodiment of the present application;

[0032] Figure 2 is a schematic flow chart of a torque control method provided in an embodiment of the present application;

[0033] Figure 3 is a structural schematic diagram of a torque control device provided in an embodiment of the present application;

[0034] Figure 4 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0035] The technical solution in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0036] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0037] Before introducing the torque control method provided in the embodiment of the present application, the implementation environment of the torque control method provided in the embodiment of the present application is first introduced. Figure 1 , Figure 1 A schematic diagram of an implementation environment of a torque control method provided in an embodiment of the present application.

[0038] For example, Figure 1As shown, the implementation environment includes: a vehicle control unit (VCU) 101 and a motor control unit (MCU) 102. The vehicle control unit 101 may also be referred to as a vehicle control unit, and the motor control unit 102 may also be referred to as a motor control unit.

[0039] The vehicle controller 101 is an important control unit of the vehicle, which can obtain relevant data of the vehicle and control the vehicle to perform corresponding operations based on the relevant data. For example, the vehicle controller can obtain the vehicle's slip rate, the vehicle's acceleration, the speed limit of the drive motor, the current speed of the drive motor, and the current output torque of the drive motor, and adjust the current output torque of the drive motor based on the multiple data.

[0040] In a possible implementation, when the vehicle controller 101 determines that the slip rate of the vehicle is greater than the slip rate threshold and the acceleration of the vehicle is greater than the acceleration threshold, the vehicle controller 101 can determine a target output torque that is less than the current output torque of the drive motor based on the speed limit of the drive motor, the current speed of the drive motor and the current output torque of the drive motor, and send the target output torque to the motor controller 102, so that the motor controller 102 reduces the current output torque of the drive motor to the target output torque to reduce the current speed of the drive motor; when it is determined that the slip rate of the vehicle is greater than the slip rate threshold and the vehicle When the acceleration is less than the acceleration threshold, a target output torque that is greater than the current output torque of the drive motor can be determined based on the speed limit of the drive motor, the current speed of the drive motor and the current output torque of the drive motor, and the target output torque can be sent to the motor controller 102, so that the motor controller 102 increases the current output torque of the drive motor by the target output torque to increase the current speed of the drive motor, thereby avoiding shaking and abnormal noise caused by a sudden change (rapid decrease or increase) in the speed of the drive motor during driving of the vehicle, thereby improving the user's driving experience.

[0041] It should be noted that Figure 1 It is only a schematic diagram of an implementation environment. In practice, the controllers interacting with the motor controller 102 may include other controllers in addition to the vehicle controller 101, and the embodiments of the present application do not make specific limitations.

[0042] Below through Figure 2 The method provided in the embodiments of the present application is described in detail.

[0043] Figure 2 It is a schematic flow chart of a torque control method provided in an embodiment of the present application.

[0044] For example, Figure 2 As shown, taking the execution subject as a vehicle controller as an example, the method 200 includes the following steps 201 to 204:

[0045] Step 201, determining the slip ratio of the vehicle.

[0046] It should be understood that the core idea of ​​the method provided in the embodiment of the present application is that when the vehicle has low adhesion, that is, when the vehicle accelerates through a speed bump (it can also be understood as when the speed of the drive motor increases rapidly), the current output torque of the drive motor is reduced to reduce the current speed of the drive motor; when the vehicle decelerates through a speed bump (it can also be understood as when the speed of the drive motor decreases rapidly), the current output torque of the drive motor is increased to increase the current speed of the drive motor, thereby avoiding the vehicle from shaking and making abnormal noises due to a sharp change (rapid decrease or increase) in the speed of the drive motor during driving, thereby improving the user's driving experience. Therefore, when implementing the method provided in the embodiment of the present application, it is necessary to first determine the slip rate of the vehicle so as to subsequently determine whether the vehicle has low adhesion, that is, whether the vehicle has passed through a speed bump, based on the slip rate of the vehicle.

[0047] It should be noted that, taking into account the different functions and force conditions of the front wheels and rear wheels of a vehicle during driving (for example, when the vehicle is a front-wheel drive vehicle, the front wheels are driving wheels and the rear wheels are driven wheels; when the vehicle is a rear-wheel drive vehicle, the front wheels are driven wheels and the rear wheels are driving wheels), in one possible implementation, the slip rate of the vehicle may include the slip rate of the front wheels of the vehicle and the slip rate of the rear wheels of the vehicle. In other words, determining the slip rate of the vehicle is to separately determine the slip rate of the front wheels of the vehicle and the slip rate of the rear wheels of the vehicle.

[0048] In a possible implementation, the front wheel slip rate of the vehicle and the rear wheel slip rate of the vehicle may be obtained in the following manner: obtaining the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed, and the acceleration of the vehicle; and determining the front wheel slip rate and the rear wheel slip rate based on the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed, and the acceleration of the vehicle.

[0049] Among them, the left front wheel speed of the vehicle can be obtained by a wheel speed sensor installed on the left front wheel, the left front wheel speed of the vehicle can be obtained by a wheel speed sensor installed on the right front wheel, the left rear wheel speed of the vehicle can be obtained by a wheel speed sensor installed on the left rear wheel, the right rear wheel speed of the vehicle can be obtained by a wheel speed sensor installed on the right rear wheel, and the left front wheel speed of the vehicle can be obtained by a wheel speed sensor installed on the left front wheel; the acceleration of the vehicle can be obtained by an acceleration sensor (also called an accelerometer) installed on the chassis or inside the body of the vehicle, which is not limited to the embodiments of the present application.

[0050] Furthermore, after obtaining the left front wheel speed, right front wheel speed, left rear wheel speed, right rear wheel speed, and the acceleration of the vehicle, the front wheel slip rate and the rear wheel slip rate can be determined based on the left front wheel speed, right front wheel speed, left rear wheel speed, right rear wheel speed, and the acceleration of the vehicle.

[0051] In a possible implementation, the front wheel slip rate and the rear wheel slip rate are determined according to the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed and the acceleration of the vehicle, including: determining the average front wheel speed according to the left front wheel speed and the right front wheel speed, and determining the average rear wheel speed according to the left rear wheel speed and the right rear wheel speed; comparing the magnitude relationship between the acceleration of the vehicle and the acceleration threshold, and when the acceleration of the vehicle is greater than the acceleration threshold, using the smaller average wheel speed of the front wheel average wheel speed and the average wheel speed of the rear wheel as a reference wheel speed; or, when the acceleration of the vehicle is less than the acceleration threshold, using the larger average wheel speed of the front wheel average wheel speed and the average wheel speed of the rear wheel as a reference wheel speed; finally, determining the front wheel slip rate according to the reference wheel speed and the average front wheel speed; determining the rear wheel slip rate according to the reference wheel speed and the average rear wheel speed.

[0052] It can be understood that in the embodiment of the present application, the acceleration threshold is used to determine whether the vehicle is in a variable speed driving state, that is, whether the vehicle is in an accelerating driving state or a decelerating driving state. Since the acceleration of the vehicle does not change when the vehicle is in a constant speed driving state, that is, the acceleration of the vehicle is 0, in a possible implementation, the acceleration threshold can be 0, that is, after the acceleration of the vehicle is obtained, the acceleration of the vehicle can be compared with the acceleration threshold (0), so as to determine the driving state of the vehicle according to the comparison result. Specifically, when the acceleration of the vehicle is greater than the acceleration threshold (0), it is determined that the vehicle is in an accelerating driving state; when the acceleration of the vehicle is less than the acceleration threshold (0), it is determined that the vehicle is in a decelerating driving state.

[0053] It should be noted that when the vehicle's acceleration is greater than the acceleration threshold, that is, when the vehicle is in an accelerated driving state, the vehicle's drive wheels (for example, the front wheels or the rear wheels) are prone to slip when the vehicle accelerates over a speed bump, resulting in the wheel speed being significantly higher than the actual vehicle speed. In this case, in order to ensure that the determined reference wheel speed is closer to the wheel speed of the wheels without slipping, the smaller average wheel speed of the front wheel average speed and the rear wheel average speed can be used as the reference wheel speed, so that the determined reference wheel speed is closer to the wheel speed of the wheels without slipping, that is, closer to the actual vehicle speed. When the vehicle's acceleration is less than the acceleration threshold, that is, when the vehicle is in an accelerated driving state, the vehicle's drive wheels (for example, the front wheels or the rear wheels) are prone to slipping when the vehicle accelerates over a speed bump, resulting in the wheel speed being significantly higher than the actual vehicle speed. In the case of decelerating driving, the vehicle's wheels are prone to slipping when the vehicle decelerates and passes over speed bumps due to excessive braking force, resulting in the wheel speed being significantly lower than the actual vehicle speed. In this case, in order to ensure that the determined reference wheel speed is closer to the wheel speed of the wheels that have not slipped, the larger average wheel speed between the front wheel average speed and the rear wheel average speed can be used as the reference wheel speed, so that the determined reference wheel speed is closer to the wheel speed of the wheels that have not slipped, that is, closer to the actual vehicle speed, thereby improving the accuracy of the wheel slip rate (rear wheel slip rate / front wheel slip rate) determined based on the reference wheel speed and the average wheel speed (rear wheel average speed / front wheel average speed).

[0054] In one possible implementation, after obtaining the average front wheel speed, the average rear wheel speed and the reference wheel speed, the average front wheel speed can be subtracted from the reference wheel speed, and the obtained difference can be compared with the reference wheel speed to obtain the front wheel slip rate; the average rear wheel speed can be subtracted from the reference wheel speed, and the obtained difference can be compared with the reference wheel speed to obtain the rear wheel slip rate.

[0055] Exemplarily, when the average front wheel speed is 130prm, the average rear wheel speed is 102prm, and the reference wheel speed is 102prm, the front wheel slip ratio = (130prm-102prm) / 102prm≈27.5%, and the rear wheel slip ratio = (102prm-102prm) / 102prm=0.

[0056] Step 202 , when the slip rate of the vehicle is greater than the slip rate threshold, in response to the vehicle being in a speed-changing driving state, obtaining a speed limit value of a drive motor of the vehicle, a current speed of the drive motor, and a current output torque of the drive motor.

[0057] Among them, the slip rate threshold is pre-set by the developer based on experimental data and stored in the internal memory of the vehicle. For example, the slip rate threshold can be ±10%, ±15% or ±20%, etc., which is not limited in the embodiments of the present application. It should be noted that when the slip rate of the vehicle is a negative value, the slip rate threshold corresponds to a negative slip rate threshold; when the slip rate of the vehicle is a positive value, the slip rate threshold corresponds to a positive slip rate threshold. Among them, when the slip rate of the vehicle is a negative value, it indicates that the wheels of the vehicle have slipped during deceleration; when the slip rate of the vehicle is a positive value, it indicates that the wheels of the vehicle have slipped during acceleration.

[0058] The implementation method of determining whether the vehicle is in a speed-changing driving state can be referred to in the above embodiment, which will not be described in detail here. It can be seen from the above embodiment that the vehicle is in a speed-changing driving state can be understood as the vehicle is in an accelerating driving state or a decelerating driving state.

[0059] It can be seen from the above embodiments that the slip rate of the vehicle includes the front wheel slip rate and the rear wheel slip rate. In the embodiments of the present application, when any one of the front wheel slip rate and the rear wheel slip rate is greater than the slip rate threshold, the speed limit of the vehicle's drive motor, the current speed of the drive motor and the current output torque of the drive motor can be obtained in response to the vehicle being in a speed-changing driving state, so as to determine the target output torque for adjusting the drive motor and adjust the current output torque of the drive motor to the target output torque, thereby increasing the application scenarios for adjusting the current output torque of the drive motor.

[0060] It should be noted that when the vehicle's slip rate is greater than the slip rate threshold and the vehicle is in a speed-changing driving state, it can be determined that the vehicle is passing through a speed bump in a decelerating or accelerating state, that is, in this case the speed of the drive motor has changed dramatically (rapidly decreased or increased), that is, it is necessary to obtain the speed limit of the vehicle's drive motor, the current speed of the drive motor and the current output torque of the drive motor in order to determine the target output torque of the drive motor based on the vehicle's slip rate, speed limit, current speed and current output torque of the drive motor, thereby adjusting the current output torque of the drive motor to the target output torque.

[0061] In a possible implementation manner, the current rotation speed of the drive motor may be acquired through a rotation speed sensor installed on the drive motor, and the current output torque of the drive motor may be acquired through a torque sensor installed on the drive motor.

[0062] In a possible implementation, the speed limit of the drive motor includes an upper speed limit and a lower speed limit, wherein the upper speed limit and the lower speed limit of the drive motor are the maximum speed and the minimum speed allowed to prevent the vehicle from losing control under specific working conditions (e.g., adhesion to the road surface).

[0063] It should be noted that when the front wheel slip rate / rear wheel slip rate of the vehicle is greater than the slip rate threshold and the acceleration of the vehicle is greater than the acceleration threshold, the speed of the drive motor will increase rapidly. At this time, the speed of the drive motor will be greater than the upper limit of the speed of the drive motor. That is, in this case, it is necessary to obtain the upper limit of the speed of the drive motor to ensure that the target output torque that is less than the current output torque of the drive motor can be determined based on the speed difference between the current speed of the drive motor and the upper limit of the speed of the drive motor, so as to control the current output torque of the drive motor to be reduced to the target output torque, thereby reducing the current speed of the drive motor to avoid the speed of the drive motor from increasing rapidly and causing the vehicle to shake. and abnormal noise; when the front wheel slip rate / rear wheel slip rate of the vehicle is greater than the slip rate threshold and the acceleration of the vehicle is less than the acceleration threshold, the speed of the drive motor will decrease rapidly. At this time, the speed of the drive motor will be less than the lower limit of the speed of the drive motor. That is, in this case, it is necessary to obtain the lower limit of the speed of the drive motor to ensure that the target output torque greater than the current output torque of the drive motor can be determined based on the speed difference between the current speed of the drive motor and the lower limit of the speed of the drive motor, so as to control the current output torque of the drive motor to increase to the target output torque, thereby increasing the current speed of the drive motor to avoid the rapid decrease in the speed of the drive motor and causing the vehicle to shake and make abnormal noise.

[0064] In a possible implementation manner, the upper speed limit and the lower speed limit of the driving motor can be obtained by: acquiring the vehicle speed; determining the upper speed limit and the lower speed limit of the motor according to the vehicle speed, the vehicle slip rate, the preset motor reduction ratio, the wheel radius and the preset coefficient;

[0065] It is understood that the motor reduction ratio refers to the ratio between the speed of the output shaft of the drive motor and the speed of the output shaft of the reducer. The motor reduction ratio is usually expressed as a ratio value, such as 10:1, which means that the motor output shaft rotates 10 times and the reducer output shaft rotates 1 time. The motor reduction ratio is pre-set by the developer according to the application requirements and stored in the vehicle's internal memory.

[0066] The wheel radius is determined by the developer using the wheel's manufacturing manual and stored in the vehicle's internal memory.

[0067] In one possible implementation, after obtaining the left front wheel speed, right front wheel speed, left rear wheel speed and right rear wheel speed of the vehicle, the average wheel speed of the left front wheel speed, right front wheel speed, left rear wheel speed and right rear wheel speed of the vehicle can be calculated, and the vehicle speed can be determined based on the average wheel speed and the wheel radius.

[0068] Among them, the method of obtaining the left front wheel speed, the right front wheel speed, the left rear wheel speed and the right rear wheel speed of the vehicle can be referred to the above embodiment and will not be repeated here.

[0069] Exemplarily, when the average wheel speed is 105 prm and the wheel radius is 0.3 m, the vehicle speed = average wheel speed (105 prm) × 2π wheel radius (0.3 m) × 60 ≈ 39584 m / h ≈ 40 km / h.

[0070] It can be seen from the above embodiments that the slip rate of the vehicle includes the front wheel slip rate and the rear wheel slip rate, that is, in a possible implementation manner, after obtaining the vehicle speed, the sum of the front wheel slip rate and the rear wheel slip rate of the vehicle can be first determined as the vehicle slip rate, and then the upper and lower speed limits of the motor can be determined based on the vehicle speed, the vehicle slip rate, the preset motor reduction ratio and the wheel radius.

[0071] Specifically, the upper limit of the motor speed can be determined by the following formula (1):

[0072]

[0073] Among them, N1 is the upper limit of the motor speed, V is the vehicle speed, n is the motor reduction ratio, k is the coefficient, R is the wheel radius, and S is the vehicle slip rate.

[0074] Specifically, the lower limit of the motor speed can be determined by the following formula (2):

[0075]

[0076] Among them, N2 is the lower limit of the motor speed, V is the vehicle speed, n is the motor reduction ratio, k is the coefficient, R is the wheel radius, and S is the vehicle slip rate.

[0077] Step 203, determining the target output torque of the drive motor according to the vehicle's slip rate, speed limit, current speed and current output torque of the drive motor. When the vehicle is in an accelerating state, the determined target output torque is less than the current output torque. When the vehicle is in a decelerating state, the determined target output torque is greater than the current output torque.

[0078] Specifically, when the vehicle's slip rate (i.e., front wheel slip rate / rear wheel slip rate) is greater than the slip rate threshold and the vehicle is in an accelerating state, the vehicle controller can determine a target output torque that is less than the current output torque based on the vehicle's front wheel slip rate / rear wheel slip rate, the upper limit of the drive motor's speed, the current speed of the drive motor, and the current output torque of the drive motor; when the vehicle's slip rate is greater than the slip rate threshold and the vehicle is in a decelerating state, the vehicle controller can determine a target output torque that is greater than the current output torque based on the vehicle's front wheel slip rate / rear wheel slip rate, the lower limit of the drive motor's speed, the current speed of the drive motor, and the current output torque of the drive motor.

[0079] The following is divided into three steps, which will introduce in detail the specific implementation method of determining the target output torque of the drive motor in step 203 according to the vehicle's slip rate, speed limit (upper speed limit / lower speed limit), current speed of the drive motor and current output torque of the drive motor.

[0080] Step (1), determining a correction factor corresponding to the slip rate of the vehicle according to a preset relationship correspondence table.

[0081] Specifically, when the front wheel slip rate / rear wheel slip rate of the vehicle is greater than the slip rate threshold and the vehicle is in a speed-changing driving state, the vehicle controller can first look up the correction factor corresponding to the front wheel slip rate / rear wheel slip rate in a preset relationship correspondence table after obtaining the speed limit (upper speed limit / lower speed limit) of the drive motor, the current speed of the drive motor and the current output torque of the drive motor, so as to subsequently correct the difference between the speed limit (upper speed limit / lower speed limit) of the drive motor and the current speed of the drive motor according to the correction factor.

[0082] Among them, the preset relationship correspondence table is pre-set by developers based on experimental data and stored in the vehicle's internal memory. In this relationship correspondence table, the larger the absolute value of the vehicle's slip rate, that is, the larger the absolute value of the front wheel slip rate / rear wheel slip rate, the larger the corresponding correction factor.

[0083] For example, the relationship between the slip rate of the vehicle and the correction factor may be shown in Table 1 below:

[0084] Table 1

[0085] Front wheel slip rate / Rear wheel slip rate …… ±0.15 ±0.3 ±0.4 ±0.5 Correction Factor …… 0.3 0.6 0.7 1

[0086] Step (2), when the acceleration of the vehicle is greater than the acceleration threshold, the difference between the upper limit of the speed of the drive motor and the current speed of the drive motor is used as the initial speed difference; when the acceleration of the vehicle is less than the acceleration threshold, the difference between the lower limit of the speed of the drive motor and the current speed of the drive motor is used as the initial speed difference.

[0087] For example, when the acceleration threshold is 0, the vehicle's acceleration is 2 m / s 2 , the upper limit of the drive motor speed is 8500prm, and the current speed of the drive motor is 9000prm. Due to the acceleration of the vehicle (2m / s 2 ) is greater than the acceleration threshold (0), that is, in this case, the upper speed limit of the drive motor (8500prm) can be subtracted from the current speed of the drive motor (9000prm), and the difference is used as the initial speed difference, that is, in this case, the initial speed difference = 8500prm-8900prm = -500prm; when the acceleration threshold is 0, the acceleration of the vehicle is -2m / s 2 , the lower limit of the drive motor speed is 8000prm, and the current speed of the drive motor is 7600prm. Due to the acceleration of the vehicle (2m / s 2 ) is less than the acceleration threshold value (0), that is, in this case, the lower limit of the speed of the drive motor (8000prm) can be subtracted from the current speed of the drive motor (7600prm), and the difference obtained is used as the initial speed difference, that is, in this case the initial speed difference = 8000prm-7600prm = 400prm.

[0088] Step (3), determining the target output torque of the drive motor according to the initial speed difference, the correction factor and the current output torque of the drive motor.

[0089] In one possible implementation, after obtaining the initial speed difference, the correction factor and the current output torque of the drive motor, the vehicle controller can first determine the corrected speed difference, i.e., the target speed difference, based on the initial speed difference and the correction factor, and then determine the target output torque of the drive motor based on the target speed difference and the current output torque of the drive motor, so as to ensure the accuracy of the determined target output torque of the drive motor.

[0090] Specifically, after obtaining the initial speed difference, correction factor and current output torque of the drive motor, the initial speed difference can be multiplied by the correction factor to obtain the corrected speed difference, that is, the target speed difference, and then the target output torque of the drive motor can be determined based on the target speed difference and the current output torque of the drive motor.

[0091] For example, when the initial speed difference is 400rpm, the correction factor is 0.6, and the current output torque of the drive motor is 300Nm, the initial speed difference (400rpm) can be multiplied by the correction factor (0.6), and the product obtained is used as the target speed difference, that is, the target speed difference = 400rpm × 0.6 = 240rpm, and then the target output torque of the drive motor is determined based on the target speed difference (240rpm) and the current output torque of the drive motor (300Nm).

[0092] In a possible implementation, the target speed difference may be subjected to proportional-integral-differential adjustment to obtain a target torque adjustment value, and then the target output torque of the drive motor may be determined based on the target torque adjustment value and the current output torque of the drive motor.

[0093] In a possible implementation, a preset one-dimensional relationship table of target speed difference and proportional gain may be stored in the vehicle, in which a larger absolute value of the target speed difference corresponds to a larger proportional gain. After determining the target speed difference, the corresponding relationship table may be searched based on the target speed difference to obtain the proportional gain.

[0094] Exemplarily, a one-dimensional relationship correspondence table of target speed difference-proportional gain may be shown in the following Table 2:

[0095] Table 2

[0096]

[0097] It can be seen from Table 2 above that the target speed difference A is less than or equal to -500rpm, corresponding to the proportional gain (0.008), the target speed difference A is greater than -500rpm and less than or equal to -300rpm, corresponding to the proportional gain (0.5), the target speed difference A is greater than or equal to 300rpm and less than 500rpm, corresponding to the proportional gain (0.5), and the target speed difference A is greater than or equal to 500rpm, corresponding to the proportional gain (0.08).

[0098] Furthermore, after obtaining the proportional gain corresponding to the target speed difference, the first torque adjustment value may be determined based on the proportional gain and the target speed difference, thereby completing the proportional adjustment of the target speed difference.

[0099] Specifically, the target speed difference may be multiplied by the proportional gain to obtain a first speed adjustment value, and then the first torque adjustment value may be determined according to a preset linear relationship and the first speed adjustment value.

[0100] It is understandable that the torque adjustment value and the speed adjustment value of the drive motor can usually be expressed by a linear relationship, for example, T = K tU, where T is the torque adjustment value of the drive motor, K t is the torque constant of the driving motor, and U is the speed adjustment value.

[0101] In a possible implementation, the target speed difference may be integrated based on a preset time period to obtain a cumulative speed difference of the drive motor within the preset time period.

[0102] Among them, the preset duration is pre-set by the developer based on experimental data. For example, the preset duration may be 5 seconds, 8 seconds, or 15 seconds, etc., and the embodiments of the present application do not limit this.

[0103] It should be noted that, in this embodiment, the target speed difference moment is integrated to obtain the cumulative speed difference of the drive motor within the preset time length, which can be understood as discrete integration of the target speed difference moment to obtain the cumulative speed difference of the drive motor within the preset time length, that is, all target speed differences within the preset time length are added up.

[0104] Specifically, the cumulative speed difference of the drive motor within a preset time period can be calculated by the following formula (3):

[0105]

[0106] Wherein, M is the cumulative speed difference, n is the target speed difference, and x is the preset duration.

[0107] In a possible implementation, a preset one-dimensional relationship table of cumulative speed difference-integral gain may be stored in the vehicle, in which the greater the absolute value of the cumulative speed difference, the greater the corresponding integral gain. After obtaining the above-mentioned cumulative speed difference, the corresponding relationship table may be searched based on the cumulative speed difference to obtain the integral gain.

[0108] Exemplarily, a one-dimensional relationship correspondence table of cumulative speed difference-integral gain may be shown in Table 3 below:

[0109] Table 3

[0110]

[0111] It can be seen from Table 3 above that the cumulative speed difference B is less than or equal to -1000rpm, corresponding to the integral gain (0.04), the cumulative speed difference B is greater than -1000rpm and less than or equal to -500rpm, corresponding to the integral gain (0.01), the cumulative speed difference B is greater than or equal to 500rpm and less than 1000rpm, corresponding to the integral gain (0.01), and the cumulative speed difference B is greater than or equal to 1000rpm, corresponding to the integral gain (0.04).

[0112] Furthermore, after obtaining the integral gain corresponding to the cumulative speed difference, the second torque adjustment value may be determined based on the integral gain and the cumulative speed difference, thereby completing the integral adjustment of the target speed difference.

[0113] Similarly, the accumulated speed difference can be multiplied by the integral gain to obtain the second speed adjustment value, and then the second torque adjustment value can be determined according to the preset linear relationship and the second speed adjustment value. For the introduction of the preset linear relationship, please refer to the above embodiment, which will not be repeated here.

[0114] In a possible implementation, a differential operation may be performed on the target speed difference based on a preset time step to obtain a rate of change of the target speed difference within the time step.

[0115] Among them, the preset time step is pre-set by the developer based on experimental data. For example, the preset time step can be 1 second or 0.5 second, etc., and the embodiment of the present application does not limit this.

[0116] Specifically, the rate of change of the target speed difference within the time step can be calculated by the following formula (4):

[0117]

[0118] Wherein, Δn is the rate of change of the target speed difference within the time step, n is the target speed difference, and t is the time step.

[0119] In a possible implementation, a one-dimensional relationship correspondence table of the change rate of the preset target speed difference within the time step and the differential gain may be stored in the vehicle, in which the larger the absolute value of the change rate of the preset target speed difference within the time step, the larger the corresponding differential gain. After obtaining the change rate of the target speed difference within the time step, the corresponding relationship correspondence table may be searched based on the change rate of the target speed difference within the time step to obtain the differential gain.

[0120] Exemplarily, a one-dimensional relationship correspondence table of the change rate of the target speed difference within the time step-differential gain can be shown in the following Table 4:

[0121] Table 4

[0122]

[0123] It can be seen from Table 4 that the change rate C of the target speed difference within the time step is less than or equal to -500rpm, corresponding to the differential gain (0.03), the cumulative speed difference B is greater than -500rpm and less than or equal to -250rpm, corresponding to the differential gain (0.02), the cumulative speed difference B is greater than or equal to 250rpm and less than 500rpm, corresponding to the differential gain (0.02), and the cumulative speed difference B is greater than or equal to 500rpm, corresponding to the differential gain (0.03).

[0124] Furthermore, after obtaining the differential gain corresponding to the rate of change of the target speed difference within the time step, the third torque adjustment value can be determined based on the rate of change of the target speed difference within the time step and the differential gain, thereby completing the differential adjustment of the target speed difference.

[0125] Similarly, the rate of change of the target speed difference within the time step can be multiplied by the differential gain to obtain the third speed adjustment value, and then the third torque adjustment value is determined according to the preset linear relationship and the third speed adjustment value. For the introduction of the preset linear relationship, please refer to the above embodiment, which will not be repeated here.

[0126] In a possible implementation, after the first torque adjustment value, the second torque adjustment value, and the third torque adjustment value are obtained, the first torque adjustment value, the second torque adjustment value, and the third torque adjustment value may be added to obtain the target torque adjustment value.

[0127] For example, when the first torque adjustment value is 45Nm, the second torque adjustment value is 35Nm, and the third torque adjustment value is 20Nm, the first torque adjustment value (45Nm), the second torque adjustment value (35Nm), and the third torque adjustment value (18Nm) can be added (summed), that is, 45Nm+35Nm+18Nm=98Nm, and the sum (98Nm) can be used as the target torque adjustment value.

[0128] In a possible implementation, after the target torque adjustment value is obtained, the target output torque of the drive motor can be determined based on the target torque adjustment value and the current output torque of the drive motor, and finally the current output torque of the drive motor can be adjusted to the target output torque.

[0129] For example, when the target torque adjustment value is 98Nm and the current output torque of the drive motor is 300Nm, the current output torque (300Nm) and the target torque adjustment value (98Nm) can be added (summed), that is, 300Nm+98Nm=398Nm, and then the sum (398Nm) can be used as the target output torque; when the target torque adjustment value is -98Nm and the current output torque of the drive motor is 300Nm, the current output torque (300) and the target torque adjustment value (-98Nm) can be added (summed), that is, 300Nm+(-98Nm)=202Nm, and then the sum (202Nm) can be used as the target output torque.

[0130] It can be understood that a positive target torque adjustment value indicates that the current output torque of the drive motor needs to be increased, and a negative target torque adjustment value indicates that the current output torque of the drive motor needs to be reduced.

[0131] Step 204 , adjusting the current output torque of the drive motor to the target output torque to adjust the rotation speed of the drive motor.

[0132] Specifically, after determining the target torque adjustment value, the vehicle controller will send the target torque adjustment value to the motor controller, so that after receiving the target torque adjustment value, the motor controller will adjust the current output torque of the drive motor to the target output torque to adjust the speed of the drive motor, that is, when the current output torque of the drive motor is reduced to a target output torque less than the current output torque, the speed of the drive motor can be reduced accordingly; when the current output torque of the drive motor is increased to a target output torque greater than the current output torque, the speed of the drive motor can be increased accordingly.

[0133] It should be noted that when the current output torque of the drive motor is reduced, the driving force of the drive motor will be reduced, making the drive motor easily affected by the load, which will cause the speed of the drive motor to decrease accordingly; on the contrary, when the current output torque of the drive motor is increased, the driving force of the drive motor will be increased, making the drive motor less affected by the load, which will cause the speed of the drive motor to increase accordingly.

[0134] For example, when the target torque adjustment value is 98Nm, the current output torque of the drive motor is 300Nm, and the target output torque of the drive motor is 398Nm, the vehicle controller will send the target torque adjustment value () to the motor controller. After receiving the target torque adjustment value (98Nm), the motor controller will increase the output torque of the drive motor from 300Nm to the target output torque (98Nm) according to the target torque adjustment value (98Nm), thereby increasing the speed of the drive motor accordingly.

[0135] In summary, the torque control method provided in the embodiment of the present application can obtain the speed limit of the vehicle's drive motor, the current speed of the drive motor, and the current output torque of the drive motor in response to the vehicle being in a speed-changing driving state (i.e., the vehicle is in an accelerating driving state or a decelerating driving state) when the vehicle's slip rate is greater than the slip rate threshold (i.e., when the vehicle passes through a speed bump); and determine the target output torque of the drive motor according to the vehicle's slip rate, speed limit, current speed, and current output torque of the drive motor; and finally adjust the current output torque of the drive motor to the target output torque, thereby adjusting the speed of the drive motor. Because the target output torque determined when the vehicle is in an accelerating driving state is less than the current output torque, and the target output torque determined when the vehicle is in a decelerating driving state is greater than the current output torque. Therefore, when the slip rate of the vehicle is greater than the slip rate threshold and the vehicle is in an accelerating state, that is, when the speed of the drive motor increases rapidly, the current output torque of the drive motor can be reduced to reduce the current speed of the drive motor; when the slip rate of the vehicle is greater than the slip rate threshold and the vehicle is in a decelerating state, that is, when the speed of the drive motor decreases rapidly, the current output torque of the drive motor can be increased to increase the current speed of the drive motor, thereby avoiding shaking and abnormal noise caused by a sudden change in the speed of the drive motor (rapid decrease or increase) during driving of the vehicle, thereby improving the user's driving experience.

[0136] Figure 3 It is a structural schematic diagram of a torque control device provided in an embodiment of the present application.

[0137] For example, Figure 3 As shown, the device 300 includes:

[0138] A determination module 301, used to determine the slip rate of the vehicle;

[0139] an acquisition module 302, configured to acquire a speed limit value of a drive motor of the vehicle, a current speed of the drive motor, and a current output torque of the drive motor in response to the vehicle being in a speed-changing driving state when the slip rate of the vehicle is greater than a slip rate threshold;

[0140] The determination module 301 is further used to determine the target output torque of the drive motor according to the slip rate, the speed limit, the current speed and the current output torque of the drive motor of the vehicle, wherein the target output torque determined when the vehicle is in an accelerating state is less than the current output torque, and the target output torque determined when the vehicle is in a decelerating state is greater than the current output torque;

[0141] The adjustment module 303 is used to adjust the current output torque of the driving motor to the target output torque, so as to adjust the rotation speed of the driving motor.

[0142] In one possible implementation, the determination module 301 is specifically used to obtain the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed, and the acceleration of the vehicle; and determine the front wheel slip rate and the rear wheel slip rate based on the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed and the acceleration of the vehicle.

[0143] In a possible implementation, the determination module 301 is further specifically used to determine the average front wheel speed based on the left front wheel speed and the right front wheel speed; determine the average rear wheel speed based on the left rear wheel speed and the right rear wheel speed; when the acceleration of the vehicle is greater than the acceleration threshold, use the smaller average wheel speed of the front wheel and the average wheel speed of the rear wheel as the reference wheel speed; or, when the acceleration of the vehicle is less than the acceleration threshold, use the larger average wheel speed of the front wheel and the average wheel speed of the rear wheel as the reference wheel speed; determine the front wheel slip rate based on the reference wheel speed and the front wheel average wheel speed; determine the rear wheel slip rate based on the reference wheel speed and the rear wheel average wheel speed.

[0144] In one possible implementation, the acquisition module 302 is specifically used to acquire the acceleration of the vehicle when the front wheel slip rate or the rear wheel slip rate is greater than a slip rate threshold; acquire the upper limit of the speed of the drive motor, the current speed of the drive motor, and the current output torque of the drive motor when the acceleration of the vehicle is greater than the acceleration threshold; or acquire the lower limit of the speed of the drive motor, the current speed of the drive motor, and the current output torque of the drive motor when the acceleration of the vehicle is less than the acceleration threshold.

[0145] In one possible implementation, the determination module 301 is further specifically used to determine a correction factor corresponding to the slip rate of the vehicle according to a preset relationship correspondence table; when the acceleration of the vehicle is greater than an acceleration threshold, the difference between the upper speed limit and the current speed of the drive motor is used as an initial speed difference; based on the initial speed difference, the correction factor and the current output torque of the drive motor, the target output torque of the drive motor is determined; or, when the acceleration of the vehicle is less than the acceleration threshold, the difference between the lower speed limit and the current speed of the drive motor is used as the initial speed difference; based on the initial speed difference, the correction factor and the current output torque of the drive motor, the target output torque of the drive motor is determined.

[0146] In a possible implementation, the determination module 301 is further configured to determine a target speed difference according to an initial speed difference and a correction factor; and to determine a target output torque of the drive motor according to the target speed difference and a current output torque of the drive motor.

[0147] In a possible implementation, the determination module 301 is further specifically used to determine a first torque adjustment value based on a preset proportional gain and a target speed difference; based on a preset time length, perform an integral operation on the target speed difference to obtain a cumulative speed difference of the drive motor within a preset time length; determine a second torque adjustment value based on a preset integral gain and the cumulative speed difference; based on a preset time step, perform a differential operation on the target speed difference to obtain a speed difference change rate of the drive motor within a preset time step; determine a third torque adjustment value based on a preset differential gain and a speed difference change rate; determine a target torque adjustment value based on the first torque adjustment value, the second torque adjustment value and the third torque adjustment value; determine a target output torque of the drive motor based on the target torque adjustment value and the current output torque of the drive motor.

[0148] Figure 4 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0149] For example, Figure 4 As shown, the vehicle 400 includes: a memory 401 and a processor 402, wherein the memory 401 stores an executable program code 403, and the processor 402 is used to call and execute the executable program code 403 to perform a torque control method.

[0150] In addition, an embodiment of the present application also protects a device, which may include a memory and a processor, wherein the memory stores an executable program code, and the processor is used to call and execute the executable program code to execute a torque control method provided by an embodiment of the present application.

[0151] In this embodiment, the functional modules of the device can be divided according to the above method example. For example, each functional module can be corresponded, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware. It should be noted that the division of modules in this embodiment is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0152] It should be noted that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, which will not be repeated here.

[0153] It should be understood that the device provided in this embodiment is used to execute the above-mentioned torque control method, and thus can achieve the same effect as the above-mentioned implementation method.

[0154] In the case of an integrated unit, the device may include a processing module and a storage module. When the device is applied to a vehicle, the processing module may be used to control and manage the actions of the vehicle. The storage module may be used to support the vehicle in executing related program codes, etc.

[0155] The processing module may be a processor or a controller, which may implement or execute various exemplary logic blocks, modules and circuits shown in conjunction with the disclosure of the present application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc. The storage module may be a memory.

[0156] In addition, the device provided in the embodiments of the present application may specifically be a chip, a component or a module, and the chip may include a connected processor and a memory; wherein the memory is used to store instructions, and when the processor calls and executes the instructions, the chip can execute a torque control method provided in the above embodiments.

[0157] This embodiment also provides a computer-readable storage medium, in which a computer program code is stored. When the computer program code is run on a computer, the computer executes the above-mentioned related method steps to implement a torque control method provided in the above embodiment.

[0158] This embodiment also provides a computer program product. When the computer program product is run on a computer, the computer is enabled to execute the above-mentioned related steps to implement a torque control method provided by the above embodiment.

[0159] Among them, the device, computer-readable storage medium, computer program product or chip provided in this embodiment is used to execute the corresponding method provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method provided above, and will not be repeated here.

[0160] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0161] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0162] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the 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.

Claims

1. A torque control method, characterized in that: The method comprises: Determine the vehicle's slip ratio; When the slip rate of the vehicle is greater than a slip rate threshold, in response to the vehicle being in a speed-changing driving state, acquiring a speed limit value of a drive motor of the vehicle, a current speed of the drive motor, and a current output torque of the drive motor; determining a target output torque of the drive motor according to the slip rate of the vehicle, the speed limit, the current speed, and the current output torque of the drive motor, wherein the target output torque determined when the vehicle is in an accelerating state is less than the current output torque, and the target output torque determined when the vehicle is in a decelerating state is greater than the current output torque; The current output torque of the driving motor is adjusted to the target output torque to adjust the rotation speed of the driving motor.

2. The method according to claim 1, characterized in that The slip rate of the vehicle includes a slip rate of the front wheels of the vehicle and a slip rate of the rear wheels of the vehicle; The determining of the slip rate of the vehicle comprises: Obtaining the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed, and the acceleration of the vehicle; The front wheel slip ratio and the rear wheel slip ratio are determined according to the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed, and the acceleration of the vehicle.

3. The method according to claim 2, characterized in that Determining the front wheel slip rate and the rear wheel slip rate according to the left front wheel speed, the right front wheel speed, the left rear wheel speed, the right rear wheel speed and the accelerator pedal opening includes: Determining an average front wheel speed according to the left front wheel speed and the right front wheel speed; Determining an average rear wheel speed according to the left rear wheel speed and the right rear wheel speed; When the acceleration of the vehicle is greater than an acceleration threshold, taking the smaller average wheel speed of the front wheel average speed and the average wheel speed of the rear wheel average speed as a reference wheel speed; Alternatively, when the acceleration of the vehicle is less than the acceleration threshold, the larger average wheel speed of the front wheel average speed and the average wheel speed of the rear wheel is used as the reference wheel speed; Determining the front wheel slip rate according to the reference wheel speed and the front wheel average wheel speed; The rear wheel slip ratio is determined according to the reference wheel speed and the rear wheel average wheel speed.

4. The method according to claim 1, characterized in that: The speed limit of the driving motor includes an upper speed limit and a lower speed limit; the slip rate of the vehicle includes a front wheel slip rate of the vehicle and a rear wheel slip rate of the vehicle; When the slip rate of the vehicle is greater than a slip rate threshold, in response to the vehicle being in a speed-changing driving state, obtaining a speed limit value of a drive motor of the vehicle, a current speed of the drive motor, and a current output torque of the drive motor includes: When the front wheel slip rate or the rear wheel slip rate is greater than the slip rate threshold, acquiring the acceleration of the vehicle; When the acceleration of the vehicle is greater than an acceleration threshold, obtaining an upper limit of the rotation speed of the drive motor, a current rotation speed of the drive motor, and a current output torque of the drive motor; Alternatively, when the acceleration of the vehicle is less than the acceleration threshold, the lower limit of the rotation speed of the drive motor, the current rotation speed of the drive motor, and the current output torque of the drive motor are acquired.

5. The method according to claim 4, characterized in that The determining the target output torque of the drive motor according to the slip rate of the vehicle, the speed limit, the current speed, and the current output torque of the drive motor includes: Determining a correction factor corresponding to the slip rate of the vehicle according to a preset relationship correspondence table; When the acceleration of the vehicle is greater than the acceleration threshold, taking the difference between the upper speed limit of the drive motor and the current speed as the initial speed difference; determining the target output torque of the drive motor according to the initial speed difference, the correction factor and the current output torque of the drive motor; Alternatively, when the acceleration of the vehicle is less than the acceleration threshold, the difference between the lower limit of the speed of the drive motor and the current speed is used as the initial speed difference; and the target output torque of the drive motor is determined based on the initial speed difference, the correction factor and the current output torque of the drive motor.

6. The method according to claim 5, characterized in that The step of determining the target output torque of the drive motor according to the initial speed difference, the correction factor and the current output torque of the drive motor comprises: Determining the target speed difference according to the initial speed difference and the correction factor; The target output torque of the drive motor is determined according to the target speed difference and the current output torque of the drive motor.

7. The method according to claim 6, characterized in that Determining the target output torque of the drive motor according to the target speed difference and the current output torque of the drive motor includes: Determining a first torque adjustment value according to a preset proportional gain and the target speed difference; Based on a preset time length, performing an integration operation on the target speed difference to obtain a cumulative speed difference of the drive motor within the preset time length; Determining a second torque adjustment value according to a preset integral gain and the accumulated speed difference; Based on a preset time step, performing a differential operation on the target speed difference to obtain a speed difference change rate of the drive motor within the preset time step; Determining a third torque adjustment value according to a preset differential gain and the speed difference change rate; determining the target torque adjustment value according to the first torque adjustment value, the second torque adjustment value and the third torque adjustment value; The target output torque of the drive motor is determined according to the target torque adjustment value and the current output torque of the drive motor.

8. A torque control device, characterized in that: The device comprises: A determination module, for determining a slip ratio of a vehicle; an acquisition module, configured to acquire, in response to the vehicle being in a speed-changing driving state, a speed limit value of a drive motor of the vehicle, a current speed of the drive motor, and a current output torque of the drive motor when the slip rate of the vehicle is greater than a slip rate threshold; a determination module, further configured to determine a target output torque of the drive motor according to the slip rate of the vehicle, the speed limit, the current speed, and the current output torque of the drive motor, wherein the target output torque determined when the vehicle is in an accelerating state is less than the current output torque, and the target output torque determined when the vehicle is in a decelerating state is greater than the current output torque; The adjustment module is used to adjust the current output torque of the driving motor to the target output torque so as to adjust the rotation speed of the driving motor.

9. A vehicle, characterized in that: The vehicle comprises: A memory for storing executable program codes; A processor, configured to call and run the executable program code from the memory, so that the vehicle executes the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed, the method according to any one of claims 1 to 7 is implemented.

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