Torque control method, device, vehicle and readable storage medium

Abstract

The present application provides a torque control method, device, vehicle, and readable storage medium. The method is applied to the field of vehicle technology and includes: determining a vehicle's slip ratio; when the vehicle's slip ratio is greater than a slip ratio threshold, in response to the vehicle being in a speed-changing driving state, obtaining a speed limit of the vehicle's drive motor, 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 based on the vehicle's slip ratio, speed limit, current speed, and current output torque of the drive motor, wherein the target output torque determined is less than the current output torque when the vehicle is accelerating and greater than the current output torque when the vehicle is decelerating; and adjusting the current output torque of the drive motor to the target output torque to adjust the speed of the drive motor. This method can prevent vehicle shaking and abnormal noise when the vehicle accelerates / decelerates over a speed bump.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and more particularly, 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 purely by the electric motor, a loud noise may occur in some scenarios. For example, when the vehicle accelerates or decelerates over a speed bump, the wheels will briefly become airborne after hitting the bump. During this time, the wheels lose traction with the road, and the contact between the wheels and the ground is instantly reduced. This momentarily reduces the load on the motor, causing the motor speed to change dramatically (rapidly increase or decrease).

[0003] However, rapid changes in motor speed can cause uneven meshing of the gears inside the transmission, leading to impact and friction between the gears and noticeable vibration and noise. These vibrations and noises degrade the driving experience, so preventing them when accelerating or decelerating over speed bumps is a pressing issue. 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; in a case where 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 based on the slip rate, speed limit, current speed, and current output torque of the drive motor, wherein 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 solution, 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 can be adjusted to the target output torque, thereby adjusting the speed of the drive motor. Since the target output torque determined when the vehicle is accelerating is less than the current output torque, and the target output torque determined when the vehicle is decelerating 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 accelerating, 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 decelerating, 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 vibration and abnormal noise caused by sudden changes in the speed of the drive motor (rapid decrease or increase) during driving of the vehicle, 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 vehicle's slip rate includes the vehicle's front wheel slip rate and the vehicle's rear wheel slip rate; determining the vehicle's slip rate includes: obtaining the vehicle's left front wheel speed, right front wheel speed, left rear wheel speed, right rear wheel speed, and vehicle acceleration; determining 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 vehicle acceleration.

[0008] In the above technical solution, it is taken into account that the vehicle's slip rate may include the front wheel slip rate and the rear wheel slip rate, that is, in one possible implementation, the front wheel slip rate and the rear wheel slip rate of the vehicle can be determined separately, so that when the front wheel slip rate / rear wheel slip rate of the vehicle is greater than the slip rate threshold, the current output torque of the drive motor can be adjusted in response to the vehicle being in a speed-changing driving state, 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 based on 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 based on the left front wheel speed and the right front wheel speed; determining 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, using the smaller average wheel speed of the front wheel average speed and the average rear 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 speed and the average rear wheel speed of the rear wheel as the reference wheel speed; determining the front wheel slip rate based on the reference wheel speed and the front wheel average speed; and determining the rear wheel slip rate based on 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 accelerating state. Since the driving wheels of the vehicle (for example, the front wheels or the rear wheels) are prone to slipping when the vehicle accelerates through 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 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 accelerating state. It is clear that the vehicle is in a decelerating state at this time. Since the wheels of the vehicle are prone to slipping due to excessive braking force when the vehicle decelerates and passes over a speed bump, the wheel speed may be significantly lower than the actual vehicle speed. That is, in this case, in order to ensure that the determined reference wheel speed is closer to the wheel speed of the wheel without slipping, the larger 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 wheel without slipping, 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 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 solution, it is taken into account that the speed limit of the drive motor includes an upper speed limit and a lower speed limit. 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. 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 speed of the drive motor from 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 based on 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 the 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 based on 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 based on 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 solution, 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 based on the target speed difference and the current output torque of the drive motor, including: determining a first torque adjustment value based on 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 based on a preset integral gain and the cumulative speed difference; performing a differential operation on 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 based on the preset differential gain and the speed difference change rate; determining the target torque adjustment value based on 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 based on 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, configured to determine a slip ratio of the vehicle;

[0019] an acquisition module, configured to acquire, in response to the vehicle being in a speed-changing driving state and when a slip ratio of the vehicle is greater than a slip ratio threshold, 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;

[0020] The determination module is further configured to determine a target output torque of the drive motor based on a slip ratio, a speed limit, a current speed, and a current output torque of the drive motor of the vehicle, wherein the target output torque determined is less than the current output torque when the vehicle is accelerating, and the target output torque determined is greater than the current output torque when the vehicle is decelerating.

[0021] The adjustment module is used to adjust the current output torque of the drive motor to the target output torque to adjust the 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 vehicle's left front wheel speed, right front wheel speed, left rear wheel speed, right rear wheel speed, and vehicle acceleration; and determine the front wheel slip rate and rear wheel slip rate based on the left front wheel speed, right front wheel speed, left rear wheel speed, right rear wheel speed, and vehicle acceleration.

[0023] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the determination module is specifically further 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 average speed and the average rear wheel speed 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 average speed and the average rear wheel speed as the reference wheel speed; determine the front wheel slip rate based on the reference wheel speed and the front wheel average speed; and determine the rear wheel slip rate based on the reference wheel speed and the rear wheel average 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 further 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 further 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 configured to store executable program code, and the processor is configured to retrieve and execute the executable program code from the memory, so that the vehicle executes the torque control method of the first aspect or any possible implementation of the first aspect.

[0029] In a fourth aspect, a computer program product is provided, comprising: 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 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 1 is a schematic structural 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 following will clearly and thoroughly describe the technical solutions in this application in conjunction with the accompanying drawings. In the description of the embodiments of this 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 this application, "multiple" means two or more than two.

[0036] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to imply or suggest relative importance or implicitly indicate the number of technical features indicated. Therefore, 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 by the embodiment of the present application, the implementation environment of the torque control method provided by the embodiment of the present application is first introduced. Figure 1 , Figure 1 A schematic diagram of the 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 can also be called a vehicle control unit, and the motor control unit 102 can also be called a motor control unit.

[0039] The vehicle controller 101 is a key control unit for the vehicle. It can acquire relevant vehicle data and control the vehicle to perform corresponding operations based on this data. For example, the vehicle controller can obtain the vehicle's slip ratio, vehicle acceleration, the drive motor's speed limit, the drive motor's current speed, and the drive motor's current output torque, and adjust the drive motor's current output torque based on this data.

[0040] In one possible embodiment, 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, it 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 is 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 vibration and abnormal noise caused by sudden changes in the speed of the drive motor (rapid decrease or increase) during driving of the vehicle, thereby improving the user's driving experience.

[0041] It should be noted that Figure 1 This is merely 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 this embodiment of the present application does not specifically limit this.

[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 the vehicle controller as an example, the method 200 includes the following steps 201 to 204:

[0045] Step 201: Determine the slip ratio of the vehicle.

[0046] It should be understood that the core concept of the method provided in the embodiments of the present application is that when the vehicle experiences low adhesion, that is, when the vehicle accelerates over a speed bump (which 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 over a speed bump (which 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. This avoids the vehicle from shaking and making abnormal noises due to a sudden 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 embodiments of the present application, it is necessary to first determine the slip rate of the vehicle so that the slip rate of the vehicle can be used to subsequently determine whether the vehicle has low adhesion, that is, whether the vehicle has passed over a speed bump.

[0047] It should be noted that, taking into account the different functions and force conditions of the front 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 embodiment, 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 determine the slip rate of the front wheels of the vehicle and the slip rate of the rear wheels of the vehicle respectively.

[0048] In one possible implementation, the front wheel slip rate of the vehicle and the rear wheel slip rate of the vehicle can be obtained by: obtaining the left front wheel speed, right front wheel speed, left rear wheel speed, 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, right front wheel speed, left rear wheel speed, 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 the wheel speed sensor installed on the left front wheel, the left front wheel speed of the vehicle can be obtained by the wheel speed sensor installed on the right front wheel, the left rear wheel speed of the vehicle can be obtained by the wheel speed sensor installed on the left rear wheel, the right rear wheel speed of the vehicle can be obtained by the wheel speed sensor installed on the right rear wheel, and the left front wheel speed of the vehicle can be obtained by the 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 this embodiment 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 vehicle acceleration, the front wheel slip rate and 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 vehicle acceleration.

[0051] In one possible implementation, the front wheel slip rate and the rear wheel slip rate are determined 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, including: determining the average front wheel speed based on the left front wheel speed and the right front wheel speed, and determining the average rear wheel speed based on the left rear wheel speed and the right rear wheel speed; comparing the acceleration of the vehicle with an 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 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 speed and the average wheel speed of the rear wheel as a reference wheel speed; finally, determining the front wheel slip rate based on the reference wheel speed and the front wheel average speed; and determining the rear wheel slip rate based on the reference wheel speed and the average wheel speed of the rear wheel.

[0052] It is 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 embodiment, the acceleration threshold can be 0, that is, after obtaining the acceleration of the vehicle, the acceleration of the vehicle can be compared with the acceleration threshold (0), so as to determine the driving state of the vehicle based on 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 accelerating 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 a wheel speed 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 non-slipping wheels, the smaller average wheel speed of the front wheel average 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 non-slipping wheels, 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 accelerating 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 a wheel speed significantly higher than the actual vehicle speed. In the case of decelerating driving, the vehicle's wheels are prone to slipping due to excessive braking force when the vehicle decelerates and passes over a speed bump, 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 non-slipping wheels, 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 non-slipping wheels, 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 front wheel average 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 rear wheel average 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] For example, 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 ratio of the vehicle is greater than a slip ratio threshold, in response to the vehicle being in a speed-changing driving state, obtain 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 vehicle's internal memory. For example, the slip rate threshold can be ±10%, ±15% or ±20%, etc., and this embodiment of the present application does not limit this. It should be noted that when the slip rate of the vehicle is negative, the slip rate threshold corresponds to a negative slip rate threshold; when the slip rate of the vehicle is positive, the slip rate threshold corresponds to a positive slip rate threshold. Among them, when the slip rate of the vehicle is negative, it indicates that the wheels of the vehicle have slipped during deceleration; when the slip rate of the vehicle is positive, it indicates that the wheels of the vehicle have slipped during acceleration.

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

[0059] It can be seen from the above embodiments that the vehicle's slip rate includes the front wheel slip rate and the rear wheel slip rate. In the embodiment 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, the current speed of the drive motor may be acquired through a 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 one 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 by the vehicle under specific operating conditions (e.g., adhered road surface) to prevent the vehicle from losing control.

[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 speed of the drive motor from decreasing rapidly and causing the vehicle to shake and make abnormal noise.

[0064] In one possible implementation, the upper and lower speed limits of the drive motor may be obtained by: acquiring a vehicle speed; and determining the upper and lower speed limits of the motor according to the vehicle speed, the vehicle slip ratio, a preset motor reduction ratio, a wheel radius, and a preset coefficient.

[0065] The motor reduction ratio is the ratio between the speed of the drive motor's output shaft and the speed of the reducer's output shaft. This ratio is typically expressed as a ratio value, such as 10:1, meaning the reducer's output shaft rotates once for every 10 revolutions of the motor's output shaft. The motor reduction ratio is pre-set by the developer based on 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] For example, 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 vehicle's slip rate includes the front wheel slip rate and the rear wheel slip rate. That is, in one possible implementation, after obtaining the vehicle speed, the sum of the vehicle's front wheel slip rate and the rear wheel slip rate can be first determined as the vehicle's slip rate. Then, based on the vehicle speed, the vehicle's slip rate, a preset motor reduction ratio, and the wheel radius, the upper and lower speed limits of the motor can be determined.

[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 based on 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 target output torque determined is less than the current output torque. When the vehicle is in a decelerating state, the target output torque determined 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 based on 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) determines 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 vehicle slip rate 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, when 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 limit of the speed of the drive motor (8500prm) can be subtracted from the current speed of the drive motor (9000prm), and the difference obtained 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, when 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 (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 obtained difference is used as the initial speed difference, that is, in this case the initial speed difference = 8000prm-7600prm = 400prm.

[0088] Step (3) determines 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 400 rpm, the correction factor is 0.6, and the current output torque of the drive motor is 300 Nm, the initial speed difference (400 rpm) can be multiplied by the correction factor (0.6), and the obtained product can be used as the target speed difference, that is, the target speed difference = 400 rpm × 0.6 = 240 rpm, and then the target output torque of the drive motor is determined based on the target speed difference (240 rpm) and the current output torque of the drive motor (300 Nm).

[0092] In one 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 one possible implementation, a preset one-dimensional correspondence table of target speed difference and proportional gain may be stored in the vehicle. In this correspondence table, a larger absolute value of the target speed difference corresponds to a larger proportional gain. After determining the target speed difference, the proportional gain may be obtained by searching the corresponding correspondence table based on the target speed difference.

[0094] For example, a one-dimensional relationship table of target speed difference-proportional gain may be shown in Table 2 below:

[0095] Table 2

[0096]

[0097] As can be seen from Table 2 above, a target speed difference A less than or equal to -500 rpm corresponds to a proportional gain of (0.008), a target speed difference A greater than -500 rpm and less than or equal to -300 rpm corresponds to a proportional gain of (0.5), a target speed difference A greater than or equal to 300 rpm and less than 500 rpm corresponds to a proportional gain of (0.5), and a target speed difference A greater than or equal to 500 rpm corresponds to a proportional gain of (0.08).

[0098] Furthermore, after obtaining the proportional gain corresponding to the target speed difference, a first torque adjustment value may be determined based on the proportional gain and the target speed difference, thereby completing 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, an integration operation may be performed on the target speed difference 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 can be 5 seconds, 8 seconds, or 15 seconds, etc., and this embodiment of the present application does 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. This can be understood as discretely integrating 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 accumulated.

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

[0105]

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

[0107] In one possible implementation, a preset one-dimensional correspondence table between cumulative speed difference and integral gain may be stored in the vehicle. In this correspondence table, a larger absolute value of the cumulative speed difference corresponds to a larger integral gain. After obtaining the cumulative speed difference, the corresponding correspondence table may be searched based on the cumulative speed difference to obtain the integral gain.

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

[0109] Table 3

[0110]

[0111] As shown in Table 3 above, when the cumulative speed difference B is less than or equal to -1000 rpm, the corresponding integral gain is (0.04); when the cumulative speed difference B is greater than -1000 rpm and less than or equal to -500 rpm, the corresponding integral gain is (0.01); when the cumulative speed difference B is greater than or equal to 500 rpm and less than 1000 rpm, the corresponding integral gain is (0.01); and when the cumulative speed difference B is greater than or equal to 1000 rpm, the corresponding integral gain is (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 a second speed adjustment value, and then the second torque adjustment value can be determined based on a preset linear relationship and the second speed adjustment value. For details about the preset linear relationship, please refer to the above embodiment and 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 seconds, etc., and this 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 using the following formula (4):

[0117]

[0118] Where 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 one possible implementation, the vehicle may store a one-dimensional relationship table between the rate of change of the preset target speed difference within a time step and the differential gain. In this relationship table, a larger absolute value of the rate of change of the preset target speed difference within a time step corresponds to a larger differential gain. After obtaining the rate of change of the target speed difference within a time step, the corresponding relationship table can be searched based on the rate of change of the target speed difference within a time step to obtain the differential gain.

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

[0121] Table 4

[0122]

[0123] From Table 4 above, it can be seen that the rate of change C of the target speed difference within the time step is less than or equal to -500 rpm, corresponding to the differential gain (0.03), the cumulative speed difference B is greater than -500 rpm and less than or equal to -250 rpm, corresponding to the differential gain (0.02), the cumulative speed difference B is greater than or equal to 250 rpm and less than 500 rpm, corresponding to the differential gain (0.02), and the cumulative speed difference B is greater than or equal to 500 rpm, 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 a third speed adjustment value. The third torque adjustment value can then be determined based on the preset linear relationship and the third speed adjustment value. For details about the preset linear relationship, please refer to the above embodiment and will not be repeated here.

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

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

[0128] In one possible implementation, after obtaining the target torque adjustment value, 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 : Adjust the current output torque of the drive motor to the target output torque to adjust the 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 more susceptible to the influence of 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 susceptible to the influence of 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.

[0135] In summary, the torque control method provided in the embodiments of the present application can, when the vehicle's slip rate is greater than a slip rate threshold (i.e., when the vehicle passes over a speed bump), respond to the vehicle being in a speed-changing driving state (i.e., when the vehicle is in an accelerating or decelerating driving state), 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; 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; and ultimately adjust the current output torque of the drive motor to the target output torque, thereby adjusting the speed of the drive motor. This is because 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. Therefore, when the vehicle's slip rate 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 vehicle's slip rate 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 sudden changes 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 is used to determine the slip ratio of the vehicle;

[0139] an acquisition module 302 for acquiring, when the slip ratio of the vehicle is greater than a slip ratio threshold and in response to the vehicle being in a speed-changing driving state, 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;

[0140] The determination module 301 is further configured to determine a target output torque of the drive motor based on the vehicle's slip ratio, speed limit, current speed, and current output torque of the drive motor, wherein the target output torque determined is less than the current output torque when the vehicle is accelerating, and the target output torque determined is greater than the current output torque when the vehicle is decelerating.

[0141] The adjustment module 303 is configured 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.

[0142] In one possible implementation, the determination module 301 is specifically used to obtain the left front wheel speed, right front wheel speed, left rear wheel speed, right rear wheel speed, and vehicle 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 vehicle acceleration.

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

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

[0147] In one 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 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; and 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 executable program code, and the processor is used to call and execute the executable program code to perform a torque control method provided by an embodiment of the present application.

[0151] In this embodiment, the device can be divided into functional modules based on the above-described method examples. For example, each functional module can be mapped to a specific functional module, or two or more functions can be integrated into a single processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and represents only a logical functional division. In actual implementation, other division methods may be used.

[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 and 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 used in a vehicle, the processing module may be used to control and manage the vehicle's movements, while the storage module may be used to support the vehicle's execution of relevant program codes.

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

[0156] In addition, the device provided in the embodiments of the present application can specifically be a chip, component or module, and the chip may include a connected processor and 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 embodiment.

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

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

[0159] Among them, the device, computer-readable storage medium, computer program product or chip provided in this embodiment are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding methods 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 distributed and completed by 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 this 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 merely schematic. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods, 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 content is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A torque control method, characterized in that: The method comprises: Determine the vehicle's slip ratio; When a slip ratio of the vehicle is greater than a slip ratio 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; determining a target output torque of the drive motor according to the slip ratio of the vehicle, the speed limit, the current speed, and the current output torque of the drive motor, wherein the target output torque determined is less than the current output torque when the vehicle is accelerating, and the target output torque determined is greater than the current output torque when the vehicle is decelerating; adjusting the current output torque of the drive motor to the target output torque to adjust the rotational speed of the drive motor; The slip ratio of the vehicle includes a slip ratio of the front wheels of the vehicle and a slip ratio of the rear wheels 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; 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 includes: determining an average front wheel speed based on the left front wheel speed and the right front wheel speed; determining an 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 an acceleration threshold, taking the smaller average wheel speed of the front wheels and the average wheel speed of the rear wheels as a reference wheel speed; Alternatively, when the acceleration of the vehicle is less than the acceleration threshold, the larger average wheel speed between the front wheel average speed and the rear wheel average speed is used as the reference wheel speed; determining the front wheel slip rate according to the reference wheel speed and the front wheel average speed; The rear wheel slip ratio is determined according to the reference wheel speed and the rear wheel average wheel speed.

2. The method according to claim 1, characterized in that 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; The step of obtaining, when the slip rate of the vehicle is greater than a slip rate threshold and 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 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 a 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.

3. The method according to claim 2, characterized in that The determining the target output torque of the drive motor according to the slip ratio 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 an initial speed difference; and 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.

4. The method according to claim 3, characterized in that The 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 includes: determining a 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.

5. The method according to claim 4, characterized in that The step of 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 a 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.

6. A torque control device, characterized in that: The device comprises: a determination module for determining a vehicle slip ratio, wherein the vehicle slip ratio includes a front wheel slip ratio and a rear wheel slip ratio; obtaining a left front wheel speed, a right front wheel speed, a left rear wheel speed, a right rear wheel speed, and an acceleration of the vehicle; determining the front wheel slip ratio and the rear wheel slip ratio 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; determining an average front wheel speed based on the left front wheel speed and the right front wheel speed; and determining an average front wheel speed based on the left rear wheel speed and the right front wheel speed. the right rear wheel speed, determining the average rear wheel speed; when the acceleration of the vehicle is greater than an acceleration threshold, using the smaller average wheel speed of the front wheel average speed and the average rear wheel speed 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 speed and the average rear wheel speed as the reference wheel speed; determining the front wheel slip rate based on the reference wheel speed and the front wheel average speed; and determining the rear wheel slip rate based on the reference wheel speed and the rear wheel average speed; an acquisition module, configured to, when a slip ratio of the vehicle is greater than a slip ratio threshold and in response to the vehicle being in a speed-changing driving state, 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; a determination module, further configured to determine a target output torque of the drive motor based on the slip ratio 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 accelerating is less than the current output torque, and the target output torque determined when the vehicle is decelerating is greater than the current output torque; The adjustment module is configured to adjust the current output torque of the drive motor to the target output torque so as to adjust the rotational speed of the drive motor.

7. A vehicle, characterized in that: The vehicle comprises: a memory for storing executable program code; A processor is 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 5.

8. 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 5 is implemented.

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