Self-adaptive control method, device and equipment for differential protection and medium

Abstract

The invention discloses a self-adaptive control method, device and equipment for differential protection and a medium. The method comprises the steps that the first wheel speed of a left wheel of a whole vehicle, the second wheel speed of a right wheel of the whole vehicle, the first road adhesion coefficient of the left wheel and the second road adhesion coefficient of the right wheel are obtained; a first speed difference is determined based on the first wheel speed and the second wheel speed. A first differential threshold is then determined based on the first road adhesion coefficient and the second road adhesion coefficient. And when the first speed difference is larger than the first speed difference threshold value, the output torque of the whole vehicle is reduced so that the first speed difference can be reduced. Through the method provided by the invention, the control parameters of differential protection can be adjusted in real time according to the actual running state and the running environment of the whole vehicle, so that the method can adapt to differential protection control functions in different scenes, the normal running of the whole vehicle is ensured, and the driving experience of a user is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to an adaptive control method, device, equipment and medium for differential protection. Background Art

[0002] The car differential is a mechanism that enables the left and right (or front and rear) drive wheels to rotate at different speeds. It is mainly composed of left and right half-shaft gears, two planetary gears and a gear rack. When the car is turning or driving on uneven roads, the left and right wheels can roll at different speeds.

[0003] One of the main reasons for the damage of the vehicle's axle shaft is that the speed difference between the left and right wheels is too large when the vehicle is driving, resulting in axle shaft wear. In order to prevent this from happening, the vehicle control unit (VCU) needs to identify such scenarios, such as single-wheel slippage of the left and right wheels on roads with different adhesion coefficients. When the speed difference between the left and right wheels is large, the differential protection function can be triggered to control and reduce the output torque of the vehicle, thereby reducing the speed difference between the left and right wheels.

[0004] However, the current differential protection usually uses the same control strategy, which cannot adapt to different scenarios. For example, in scenarios with a large road adhesion coefficient and rainy days, using the same differential protection function will affect the normal power performance of the vehicle and the user's driving experience. Summary of the invention

[0005] In view of this, the present application provides an adaptive control method, device, equipment and medium for differential protection, so as to realize the differential protection control function in different scenarios and improve the user's driving experience.

[0006] In a first aspect, the present application provides an adaptive control method for differential protection, the method comprising:

[0007] Acquire a first wheel speed of a left wheel and a second wheel speed of a right wheel of the vehicle, as well as a first road adhesion coefficient of the left wheel and a second road adhesion coefficient of the right wheel;

[0008] determining a first speed difference based on the first wheel speed and the second wheel speed;

[0009] determining a first speed difference threshold based on the first road adhesion coefficient and the second road adhesion coefficient;

[0010] When the first speed difference is greater than the first speed difference threshold, the output torque of the entire vehicle is reduced to reduce the first speed difference.

[0011] In a possible implementation manner, after determining the first speed difference based on the first wheel speed and the second wheel speed, the method further includes:

[0012] determining a first speed difference change rate based on the first wheel speed and the second wheel speed;

[0013] determining a first speed difference integral based on the first speed difference and the first speed difference change rate;

[0014] determining a first speed difference integral threshold based on the first road surface adhesion coefficient, the second road surface adhesion coefficient, and the first speed difference change rate;

[0015] When the first speed difference is greater than the first speed difference threshold, before reducing the output torque of the entire vehicle, the method further includes:

[0016] It is determined whether the first speed difference integral is greater than the first speed difference integral threshold; if so, the output torque of the entire vehicle is reduced.

[0017] In a possible implementation, the method further includes:

[0018] Obtain the second speed difference integral and the second speed difference integral threshold of the whole vehicle;

[0019] When the second speed difference integral is less than or equal to the second speed difference integral threshold, the output torque of the entire vehicle is increased to the required torque.

[0020] In a possible implementation manner, determining the first speed difference integral based on the first speed difference and the first speed difference change rate includes:

[0021] Determine a speed difference integral coefficient based on the first speed difference and the first speed difference change rate, wherein the speed difference integral coefficient is positively correlated with the first speed difference and the first speed difference change rate;

[0022] The first speed difference integral coefficient and the first speed difference are integrated over time to determine the first speed difference integral.

[0023] In a possible implementation, determining a first speed difference integral threshold based on the first road surface adhesion coefficient, the second road surface adhesion coefficient, and the first speed difference change rate includes:

[0024] determining an absolute value of a difference in a road surface adhesion coefficient based on the first road surface adhesion coefficient and the second road surface adhesion coefficient;

[0025] The first speed difference integral threshold is determined based on the absolute value of the difference and the first speed difference change rate, and the first speed difference integral threshold is negatively correlated with the absolute value of the difference and the first speed difference change rate.

[0026] In a possible implementation, reducing the output torque of the vehicle includes:

[0027] Obtain the required torque and current output torque of the vehicle;

[0028] determining a torque decrease slope based on the first road adhesion coefficient, the second road adhesion coefficient, the required torque, and the current output torque;

[0029] The entire vehicle is controlled to reduce the output torque at the torque reduction slope.

[0030] In a possible implementation, determining the torque decrease slope based on the first road adhesion coefficient, the second road adhesion coefficient, the required torque, and the current output torque includes:

[0031] determining an absolute value of a difference in a road surface adhesion coefficient based on the first road surface adhesion coefficient and the second road surface adhesion coefficient;

[0032] determining an absolute value of a torque difference based on the required torque and the current output torque;

[0033] The torque reduction slope is determined based on the absolute value of the difference in the road adhesion coefficient and the absolute value of the torque difference.

[0034] In a possible implementation, determining a first speed difference threshold based on the first road surface adhesion coefficient and the second road surface adhesion coefficient includes:

[0035] determining an absolute value of a difference in a road surface adhesion coefficient based on the first road surface adhesion coefficient and the second road surface adhesion coefficient;

[0036] The first speed difference threshold is determined according to the absolute value of the difference, and the first speed difference threshold is negatively correlated with the absolute value of the difference.

[0037] In a possible implementation, determining a speed difference integral coefficient based on the first speed difference and the first speed difference change rate includes:

[0038] Obtaining a predetermined speed difference integral coefficient lookup table, wherein the speed difference integral coefficient lookup table includes a correlation relationship between a speed difference, a speed difference change rate, and a speed difference integral coefficient;

[0039] The speed difference integral coefficient corresponding to the first speed difference and the first speed difference change rate is determined in the speed difference integral coefficient lookup table.

[0040] In a second aspect, the present application provides an adaptive control device for differential protection, the device comprising:

[0041] A first acquisition unit is used to acquire a first wheel speed of a left wheel and a second wheel speed of a right wheel of the vehicle, as well as a first road adhesion coefficient of the left wheel and a second road adhesion coefficient of the right wheel;

[0042] a first determining unit, configured to determine a first speed difference based on the first wheel speed and the second wheel speed;

[0043] a second determining unit, configured to determine a first speed difference threshold based on the first road adhesion coefficient and the second road adhesion coefficient;

[0044] A control unit is used to reduce the output torque of the entire vehicle when the first speed difference is greater than the first speed difference threshold so as to reduce the first speed difference.

[0045] In a possible implementation manner, the device further includes: a third determining unit and a fourth determining unit;

[0046] After determining the first speed difference based on the first wheel speed and the second wheel speed, the first determining unit is further configured to determine a first speed difference change rate based on the first wheel speed and the second wheel speed;

[0047] The third determining unit is used to determine a first speed difference integral based on the first speed difference and the first speed difference change rate;

[0048] The fourth determining unit is configured to determine a first speed difference integral threshold value based on the first road surface adhesion coefficient, the second road surface adhesion coefficient, and the first speed difference change rate;

[0049] The device further comprises: a judgment unit;

[0050] When the first speed difference is greater than the first speed difference threshold, before reducing the output torque of the whole vehicle, the judgment unit is used to judge whether the first speed difference integral is greater than the first speed difference integral threshold. If so, the control unit is used to reduce the output torque of the whole vehicle.

[0051] In a possible implementation manner, the device further includes: a second acquisition unit;

[0052] The second acquisition unit is used to acquire a second speed difference integral and a second speed difference integral threshold of the whole vehicle;

[0053] The control unit is further configured to increase the output torque of the entire vehicle to a required torque when the second speed difference integral is less than or equal to the second speed difference integral threshold.

[0054] In one possible implementation, the third determination unit is specifically used to determine a speed difference integral coefficient based on the first speed difference and the first speed difference change rate, and the speed difference integral coefficient is positively correlated with the first speed difference and the first speed difference change rate; the first speed difference integral coefficient and the first speed difference are integrated over time to determine the first speed difference integral.

[0055] In one possible implementation, the fourth determination unit is specifically used to determine the absolute value of the difference between the first road adhesion coefficient and the second road adhesion coefficient; based on the absolute value of the difference and the first speed difference change rate, determine the first speed difference integral threshold, and the first speed difference integral threshold is negatively correlated with the absolute value of the difference and the first speed difference change rate.

[0056] In one possible implementation, the control unit is specifically used to obtain the required torque and current output torque of the whole vehicle; determine the torque reduction slope based on the first road adhesion coefficient, the second road adhesion coefficient, the required torque and the current output torque; and control the whole vehicle to reduce the output torque at the torque reduction slope.

[0057] In one possible implementation, the control unit is specifically used to determine the absolute value of the difference in road adhesion coefficients based on the first road adhesion coefficient and the second road adhesion coefficient; determine the absolute value of the torque difference based on the required torque and the current output torque; and determine the torque decrease slope based on the absolute value of the difference in road adhesion coefficients and the absolute value of the torque difference.

[0058] In a possible implementation, the second determination unit is specifically used to determine the absolute value of the difference between the first road adhesion coefficient and the second road adhesion coefficient; determine the first speed difference threshold according to the absolute value of the difference, and the first speed difference threshold is negatively correlated with the absolute value of the difference.

[0059] In one possible implementation, the third determination unit is specifically used to obtain a predetermined speed difference integral coefficient lookup table, wherein the speed difference integral coefficient lookup table includes an association between speed difference, speed difference change rate and speed difference integral coefficient; and determine the speed difference integral coefficient corresponding to the first speed difference and the first speed difference change rate in the speed difference integral coefficient lookup table.

[0060] In a third aspect, the present application provides an adaptive control device for differential protection, the device comprising: a memory and a processor;

[0061] The memory is used to store relevant program codes;

[0062] The processor is used to call the program code to execute the adaptive control method for differential protection described in any one of the implementations of the first aspect above.

[0063] In a fourth aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store a computer program, and the computer program is used to execute the adaptive control method for differential protection described in any one of the implementations of the first aspect above.

[0064] It can be seen that this application has the following beneficial effects:

[0065] In the above implementation of the present application, the first wheel speed of the left wheel and the second wheel speed of the right wheel of the whole vehicle, as well as the first road adhesion coefficient of the left wheel and the second road adhesion coefficient of the right wheel are obtained. The first speed difference is determined based on the first wheel speed and the second wheel speed. Then the first speed difference threshold is determined based on the first road adhesion coefficient and the second road adhesion coefficient. When the first speed difference is greater than the first speed difference threshold, the output torque of the whole vehicle is reduced to reduce the first speed difference. Through the method provided by the present application, the control parameters of the differential protection can be adjusted in real time according to the actual operating state of the whole vehicle and the operating environment, so as to adapt to the differential protection control function in different scenarios, ensure the normal operation of the whole vehicle, and improve the user's driving experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. It is obvious that the drawings described below are only some embodiments provided in the present application, and a person skilled in the art can also obtain other drawings based on these drawings.

[0067] Figure 1 A flowchart of an adaptive control method for differential protection provided in an embodiment of the present application;

[0068] Figure 2 A schematic diagram of an adaptive control device for differential protection provided in an embodiment of the present application;

[0069] Figure 3 A schematic diagram of an adaptive control device for differential protection provided in an embodiment of the present application. DETAILED DESCRIPTION

[0070] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. The described embodiments are only exemplary implementation methods of the present application, not all implementation methods. Those skilled in the art can combine the embodiments of the present application to obtain other embodiments without creative work, and these embodiments are also within the scope of protection of the present application.

[0071] The car differential is a mechanism that enables the left and right (or front and rear) wheels to rotate at different speeds. It is mainly composed of left and right half-axle gears, two planetary gears and a gear rack. When the car is turning or driving on uneven roads, the left and right wheels can roll at different speeds.

[0072] The power output by the engine enters the differential through the drive shaft, drives the planetary wheel carrier, and then the planetary wheels drive the left and right half-axles to drive the left and right wheels respectively to drive the vehicle. One of the main reasons for damage to the vehicle's half-axles is that when the vehicle is driving, the speed difference between the left and right wheels is too large, causing the half-axles to wear. In order to prevent this operating condition from occurring, the vehicle controller VCU needs to identify such scenarios, such as single-wheel slippage on roads with different adhesion coefficients between the left and right wheels. When the speed difference between the left and right wheels is large, that is, the speed difference between the left and right half-axles is large, the differential protection function can be triggered to control and reduce the output torque of the vehicle, thereby reducing the speed difference between the left and right wheels and reducing the risk of differential failure.

[0073] However, the current differential protection function usually uses the same control strategy, such as reducing the vehicle's output torque when the wheel speed difference exceeds a fixed value, which cannot adapt to different scenarios. For example, in scenarios with a large road adhesion coefficient and rainy days, using the same differential protection function may affect the normal power performance of the vehicle and affect the user experience.

[0074] Based on this, an embodiment of the present application provides an adaptive control method for differential protection, so as to realize the differential protection control function in different scenarios and improve the user's driving experience. In specific implementation, the first wheel speed of the left wheel and the second wheel speed of the right wheel of the whole vehicle, as well as the first road adhesion coefficient of the left wheel and the second road adhesion coefficient of the right wheel are obtained. The first speed difference is determined based on the first wheel speed and the second wheel speed. Then the first speed difference threshold is determined based on the first road adhesion coefficient and the second road adhesion coefficient. When the first speed difference is greater than the first speed difference threshold, the output torque of the whole vehicle is reduced to reduce the first speed difference. Through the method provided by the present application, the control parameters of the differential protection can be adjusted in real time according to the actual operating state of the whole vehicle and the operating environment, so as to adapt to the differential protection control function in different scenarios, ensure the normal operation of the whole vehicle, and improve the user's driving experience.

[0075] In order to facilitate the understanding of the technical solution provided by the embodiments of the present application, a detailed introduction will be given below with reference to the accompanying drawings.

[0076] See also Figure 1 , Figure 1 A flowchart of an adaptive control method for differential protection provided in an embodiment of the present application.

[0077] The method may be executed by a control device of the vehicle, for example, a vehicle controller VCU.

[0078] The method may include the following steps:

[0079] S101: Obtain a first wheel speed of a left wheel and a second wheel speed of a right wheel of the vehicle, as well as a first road adhesion coefficient of the left wheel and a second road adhesion coefficient of the right wheel.

[0080] In a possible implementation, the VCU may obtain a first wheel speed of a left wheel and a second wheel speed of a right wheel through a wheel speed sensor of the vehicle, where the wheel speed indicates a rotation speed of the wheel.

[0081] In one possible implementation, the whole vehicle model can be simulated and designed to obtain parameters such as the slip rate and adhesion rate of the vehicle under road conditions. The adhesion rate represents the ratio of the ground tangential reaction force caused by the torque acting on the wheel to the normal reaction force of the wheel. Then, the μ-s curve can be determined based on the slip rate and adhesion rate to represent the relationship between the slip rate and the adhesion rate. As the slip rate increases, the adhesion rate first increases and then decreases. According to the μ-s curve, the maximum adhesion rate can be determined, which is the road adhesion coefficient.

[0082] In addition, different methods of calculating the road adhesion coefficient can also be determined according to the existing dynamic model, so as to determine the first road adhesion coefficient of the left wheel and the second road adhesion coefficient of the right wheel. The above is only an exemplary description, and the embodiment of the present application does not limit the method of determining the road adhesion coefficient.

[0083] S102: Determine a first speed difference based on the first wheel speed and the second wheel speed.

[0084] After the first wheel speed of the left wheel and the second wheel speed of the right wheel are acquired, a first speed difference between the first wheel speed and the second wheel speed may be determined.

[0085] S103: Determine a first speed difference threshold based on the first road adhesion coefficient and the second road adhesion coefficient.

[0086] When determining the first speed difference threshold, it can be achieved in the following manner: first, based on the first road adhesion coefficient and the second road adhesion coefficient, the absolute value of the difference of the road adhesion coefficient is determined. That is, after the difference between the first road adhesion coefficient and the second road adhesion coefficient is calculated, the absolute value of the difference is calculated. Then the first speed difference threshold is determined according to the absolute value of the difference. Among them, the first speed difference threshold is negatively correlated with the absolute value of the difference, that is, the larger the absolute value of the difference, the smaller the first speed difference threshold, so that when the road adhesion coefficient of the left wheel and the road adhesion coefficient of the right wheel differ greatly, the torque reduction intervention of the differential protection can be performed as soon as possible to prevent the speed difference from further expanding.

[0087] It should be noted that the embodiment of the present application does not limit the corresponding relationship between the absolute value of the difference in road adhesion coefficient and the first speed difference threshold, which can be a linear function relationship, and satisfy the negative correlation between the first speed difference threshold and the absolute value of the difference. For example, the first speed difference threshold = a + b * |difference in road adhesion coefficient|, and b < 0.

[0088] In addition, the correspondence between the absolute value of the difference in road adhesion coefficient and the first speed difference threshold may also be a table, which includes a plurality of absolute values ​​of the difference in road adhesion coefficient and the first speed difference thresholds corresponding thereto. The table may be predetermined based on experiments.

[0089] The embodiment of the present application does not limit the execution order between step S102 and step S103, that is, step S102 can be executed first and then step S103, or step S103 can be executed first and then step S102, or step S102 and step S103 can be executed simultaneously, all of which will not affect the implementation of the embodiment of the present application.

[0090] S104: When the first speed difference is greater than a first speed difference threshold, the output torque of the entire vehicle is reduced to reduce the first speed difference.

[0091] When it is determined that the first speed difference between the left wheel and the right wheel is greater than the first speed difference threshold, it indicates that the wheel speed difference between the left wheel and the right wheel is large. At this time, the output torque of the whole vehicle can be controlled to reduce so as to reduce the speed difference between the left wheel and the right wheel.

[0092] In a possible implementation, the output torque of the whole vehicle can be reduced in the following manner to obtain the required torque and current output torque of the whole vehicle. The torque reduction slope is determined based on the first road adhesion coefficient, the second road adhesion coefficient, the required torque and the current output torque. Then the whole vehicle is controlled to reduce the output torque at the torque reduction slope. Among them, the required torque can be determined based on the analysis of the accelerator pedal signal of the whole vehicle, which is not specifically introduced in the embodiment of the present application.

[0093] In specific implementation, the absolute value of the difference of the road adhesion coefficient is first determined based on the first road adhesion coefficient and the second road adhesion coefficient. The absolute value of the torque difference is determined based on the required torque of the vehicle and the current output torque. Then, the torque reduction slope is determined based on the absolute value of the difference of the road adhesion coefficient and the absolute value of the torque difference.

[0094] It should be noted that the embodiment of the present application does not limit the specific implementation method of determining the torque drop slope based on the absolute value of the difference in road adhesion coefficient and the absolute value of the torque difference. For example, the torque drop slope can be determined based on the product of the absolute value of the difference in road adhesion coefficient and the absolute value of the torque difference. And it is satisfied that when the absolute value of the difference in road adhesion coefficient is larger, the torque drop slope is larger, so that when the road adhesion coefficient of the left wheel and the road adhesion coefficient of the right wheel differ greatly, the torque reduction intervention of the differential protection is performed as soon as possible to prevent the speed difference from further expanding.

[0095] In addition, the correspondence between the absolute value of the difference in road adhesion coefficient, the absolute value of the torque difference and the torque drop slope can also be a table, in which a torque drop slope can be uniquely determined according to the combination of any absolute value of the difference in road adhesion coefficient and any absolute value of the torque difference. The table can be predetermined according to experiments.

[0096] In the above embodiment, the control method of differential protection can be determined according to the wheel speeds of the left and right wheels, that is, according to the conditions satisfied by the speed difference, the control parameters (speed difference threshold) are adjusted in real time to determine the control strategy for reducing the output torque of the whole vehicle, so as to realize the differential protection control function in different scenarios and improve the user's driving experience.

[0097] In a possible implementation, in order to improve the accuracy of the control method for differential protection, after determining the first speed difference between the left wheel and the right wheel, a speed difference integral threshold may also be determined, so as to determine the condition for reducing the output torque of the entire vehicle according to the speed difference integral threshold. Specifically, the following steps A1-A4 may be included:

[0098] A1: Determine a first speed difference change rate based on the first wheel speed and the second wheel speed.

[0099] The first speed difference change rate may represent the degree of change of the speed difference over time, for example, it may be represented as the ratio between the difference between the speed difference at the current moment and the speed difference at the next moment and the interval moment.

[0100] A2: Determine the first speed difference integral based on the first speed difference and the first speed difference change rate.

[0101] In a possible implementation, the first speed differential integral can be determined in the following manner: first, the speed differential integral coefficient is determined based on the first speed differential and the first speed differential change rate. The speed differential integral coefficient is positively correlated with the first speed differential and the first speed differential change rate. That is, the larger the speed differential and the larger the first speed differential change rate, the larger the speed differential integral coefficient.

[0102] The embodiments of the present application do not limit the implementation method of determining the speed differential integral coefficient based on the first speed differential and the first speed differential change rate. It can be determined based on an existing dynamic model, or it can be determined based on a speed differential integral coefficient lookup table. Among them, the speed differential integral coefficient lookup table can be predetermined based on experiments. The speed differential integral coefficient lookup table includes the correlation between the speed difference, the speed differential change rate and the speed differential integral coefficient. Any speed difference and any speed differential change rate are combined to uniquely determine a speed differential integral coefficient. Therefore, after obtaining the speed differential integral coefficient lookup table, the speed differential integral coefficient corresponding to the first speed difference and the first speed differential change rate can be determined.

[0103] Then the first speed differential integral coefficient and the first speed differential are integrated over time to determine the first speed differential integral. For example, it can be expressed as speed differential integral = ∫ (K*speed differential) dt, K is the speed differential integral coefficient, K = f (speed differential, speed differential change rate). The speed differential integral can be understood as the wear index of the differential hardware (such as the half shaft), and the larger the index, the greater the degree of wear of the differential hardware.

[0104] A3: Determine a first speed difference integral threshold based on the first road surface adhesion coefficient, the second road surface adhesion coefficient, and the first speed difference change rate.

[0105] Specifically, it can be achieved in the following manner: first, the absolute value of the difference between the first road adhesion coefficient and the second road adhesion coefficient is determined. Then, based on the absolute value of the difference and the first speed difference change rate, the first speed difference integral threshold is determined. The first speed difference integral threshold is negatively correlated with the absolute value of the difference and the first speed difference change rate.

[0106] It should be noted that the embodiment of the present application does not limit the specific implementation method of determining the first speed difference integral threshold value based on the absolute value of the difference in road adhesion coefficient and the first speed difference change rate. For example, it can be determined according to a lookup table of the speed difference integral threshold value, and the lookup table can be predetermined according to experiments. Among them, the lookup table includes the correspondence between the absolute value of the difference in road adhesion coefficient, the speed difference change rate and the speed difference integral threshold value. The absolute value of the difference in any road adhesion coefficient and any speed difference change rate are combined to uniquely determine a speed difference integral threshold value. In addition, the functional relationship between the speed difference integral threshold value and the absolute value of the difference in road adhesion coefficient and the speed difference change rate can also be fitted using tools such as matlab according to the lookup table of the speed difference integral threshold value, and the speed difference integral threshold value is subsequently determined according to the functional relationship.

[0107] A4: Determine whether the first speed difference integral is greater than the first speed difference integral threshold. If so, reduce the output torque of the vehicle.

[0108] After determining the first speed differential integral and the first speed differential integral threshold, it is determined whether the first speed differential integral is greater than the first speed differential integral threshold. If so, it indicates that the differential protection condition is triggered and the output torque of the vehicle needs to be controlled to be reduced. The specific control method can be referred to the above method embodiment and will not be repeated here.

[0109] Since the vehicle controller can obtain the driving status parameters of the vehicle in real time, when the output torque is reduced, if the speed difference between the left wheel and the right wheel decreases and there is no need to trigger the differential protection, the output torque of the vehicle can be gradually increased to the required torque to meet the driving needs of the vehicle.

[0110] In one possible implementation, the second speed differential integral and the second speed differential integral threshold of the entire vehicle can be reacquired. When the second speed differential integral is less than or equal to the second speed differential integral threshold, it indicates that there is no need to trigger differential protection. At this time, the output torque of the entire vehicle can be controlled to slowly increase to the required torque.

[0111] Specifically, the third wheel speed of the left wheel and the fourth wheel speed of the right wheel, as well as the third road adhesion coefficient of the left wheel and the fourth road adhesion coefficient of the right wheel can be obtained. The second speed difference and the second speed difference change rate are determined based on the third wheel speed and the fourth wheel speed. The second speed difference threshold is determined based on the third road adhesion coefficient and the fourth road adhesion coefficient. The first speed difference integral is determined based on the second speed difference and the second speed difference change rate. The second speed difference integral threshold is determined based on the third road adhesion coefficient, the fourth road adhesion coefficient and the second speed difference change rate.

[0112] Among them, the specific implementation method of the second speed difference integral and the second speed difference integral threshold can refer to the process of determining the first speed difference integral and the first speed difference integral threshold in the above method embodiment, which will not be repeated here.

[0113] Through the method provided in the embodiment of the present application, the control parameters of the differential protection can be adjusted in real time according to the actual operating status of the vehicle and the operating environment, so as to adapt to the differential protection control function in different scenarios, ensure the normal operation of the vehicle, and improve the user's driving experience.

[0114] Based on the above method embodiment, the present application embodiment also provides an adaptive control device for differential protection. Figure 2 , Figure 2 A schematic diagram of an adaptive control device for differential protection provided in an embodiment of the present application.

[0115] The device 200 comprises:

[0116] The first acquisition unit 201 is used to acquire a first wheel speed of a left wheel and a second wheel speed of a right wheel of the vehicle, as well as a first road adhesion coefficient of the left wheel and a second road adhesion coefficient of the right wheel;

[0117] A first determining unit 202, configured to determine a first speed difference based on the first wheel speed and the second wheel speed;

[0118] A second determining unit 203, configured to determine a first speed difference threshold based on the first road adhesion coefficient and the second road adhesion coefficient;

[0119] The control unit 204 is configured to reduce the output torque of the entire vehicle when the first speed difference is greater than the first speed difference threshold, so as to reduce the first speed difference.

[0120] In a possible implementation manner, the device further includes: a third determining unit and a fourth determining unit;

[0121] After determining the first speed difference based on the first wheel speed and the second wheel speed, the first determining unit 202 is further configured to determine a first speed difference change rate based on the first wheel speed and the second wheel speed;

[0122] The third determining unit is used to determine a first speed difference integral based on the first speed difference and the first speed difference change rate;

[0123] The fourth determining unit is configured to determine a first speed difference integral threshold value based on the first road surface adhesion coefficient, the second road surface adhesion coefficient, and the first speed difference change rate;

[0124] The device further comprises: a judgment unit;

[0125] When the first speed difference is greater than the first speed difference threshold, before reducing the output torque of the whole vehicle, the judgment unit is used to judge whether the first speed difference integral is greater than the first speed difference integral threshold. If so, the control unit is used to reduce the output torque of the whole vehicle.

[0126] In a possible implementation manner, the device further includes: a second acquisition unit;

[0127] The second acquisition unit is used to acquire a second speed difference integral and a second speed difference integral threshold of the whole vehicle;

[0128] The control unit 204 is further configured to increase the output torque of the vehicle to a required torque when the second speed difference integral is less than or equal to the second speed difference integral threshold.

[0129] In one possible implementation, the third determination unit is specifically used to determine a speed difference integral coefficient based on the first speed difference and the first speed difference change rate, and the speed difference integral coefficient is positively correlated with the first speed difference and the first speed difference change rate; the first speed difference integral coefficient and the first speed difference are integrated over time to determine the first speed difference integral.

[0130] In one possible implementation, the fourth determination unit is specifically used to determine the absolute value of the difference between the first road adhesion coefficient and the second road adhesion coefficient; based on the absolute value of the difference and the first speed difference change rate, determine the first speed difference integral threshold, and the first speed difference integral threshold is negatively correlated with the absolute value of the difference and the first speed difference change rate.

[0131] In one possible implementation, the control unit 204 is specifically used to obtain the required torque and current output torque of the whole vehicle; determine the torque reduction slope based on the first road adhesion coefficient, the second road adhesion coefficient, the required torque and the current output torque; and control the whole vehicle to reduce the output torque at the torque reduction slope.

[0132] In one possible implementation, the control unit 204 is specifically used to determine the absolute value of the difference between the road adhesion coefficients based on the first road adhesion coefficient and the second road adhesion coefficient; determine the absolute value of the torque difference based on the required torque and the current output torque; and determine the torque decrease slope based on the absolute value of the difference between the road adhesion coefficients and the absolute value of the torque difference.

[0133] In a possible implementation, the second determination unit 203 is specifically used to determine the absolute value of the difference between the first road adhesion coefficient and the second road adhesion coefficient; determine the first speed difference threshold according to the absolute value of the difference, and the first speed difference threshold is negatively correlated with the absolute value of the difference.

[0134] In one possible implementation, the third determination unit is specifically used to obtain a predetermined speed difference integral coefficient lookup table, wherein the speed difference integral coefficient lookup table includes an association between speed difference, speed difference change rate and speed difference integral coefficient; and determine the speed difference integral coefficient corresponding to the first speed difference and the first speed difference change rate in the speed difference integral coefficient lookup table.

[0135] Based on the above method embodiment and device embodiment, the present application embodiment further provides an adaptive control device for differential protection, which will be described below in conjunction with the accompanying drawings.

[0136] See also Figure 3 , Figure 3 A schematic diagram of an adaptive control device for differential protection provided in an embodiment of the present application.

[0137] The device 300 includes: a memory 301 and a processor 302;

[0138] The memory 301 is used to store relevant program codes;

[0139] The processor 302 is used to call the program code to execute the adaptive control method for differential protection described in the above method embodiment.

[0140] In addition, an embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store a computer program, and the computer program is used to execute the adaptive control method for differential protection described in the above method embodiment.

[0141] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can refer to each other. In particular, for the system or device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The device embodiment described above is only exemplary, in which the units or modules described as separate components may or may not be physically separated, and the components displayed as units or modules may or may not be physical modules, that is, they may be located in one place, or they may be distributed on multiple network units, and some or all of the units or modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative work.

[0142] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0143] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0144] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0145] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An adaptive control method for differential protection, characterized in that: The method comprises: Acquire a first wheel speed of a left wheel and a second wheel speed of a right wheel of the vehicle, as well as a first road adhesion coefficient of the left wheel and a second road adhesion coefficient of the right wheel; determining a first speed difference based on the first wheel speed and the second wheel speed; determining a first speed difference threshold based on the first road adhesion coefficient and the second road adhesion coefficient; When the first speed difference is greater than the first speed difference threshold, the output torque of the entire vehicle is reduced to reduce the first speed difference.

2. The method according to claim 1, characterized in that: After determining a first speed difference based on the first wheel speed and the second wheel speed, the method further includes: determining a first speed difference change rate based on the first wheel speed and the second wheel speed; determining a first speed difference integral based on the first speed difference and the first speed difference change rate; determining a first speed difference integral threshold based on the first road surface adhesion coefficient, the second road surface adhesion coefficient, and the first speed difference change rate; When the first speed difference is greater than the first speed difference threshold, before reducing the output torque of the entire vehicle, the method further includes: It is determined whether the first speed difference integral is greater than the first speed difference integral threshold; if so, the output torque of the entire vehicle is reduced.

3. The method according to claim 2, characterized in that The method further comprises: Obtain the second speed difference integral and the second speed difference integral threshold of the whole vehicle; When the second speed difference integral is less than or equal to the second speed difference integral threshold, the output torque of the entire vehicle is increased to the required torque.

4. The method according to claim 2, characterized in that: The determining a first speed difference integral based on the first speed difference and the first speed difference change rate comprises: Determine a speed difference integral coefficient based on the first speed difference and the first speed difference change rate, wherein the speed difference integral coefficient is positively correlated with the first speed difference and the first speed difference change rate; The first speed difference integral coefficient and the first speed difference are integrated over time to determine the first speed difference integral.

5. The method according to claim 2, characterized in that: The determining a first speed difference integral threshold based on the first road surface adhesion coefficient, the second road surface adhesion coefficient, and the first speed difference change rate includes: determining an absolute value of a difference in a road surface adhesion coefficient based on the first road surface adhesion coefficient and the second road surface adhesion coefficient; The first speed difference integral threshold is determined based on the absolute value of the difference and the first speed difference change rate, and the first speed difference integral threshold is negatively correlated with the absolute value of the difference and the first speed difference change rate.

6. The method according to claim 1, characterized in that The reducing the output torque of the whole vehicle comprises: Obtain the required torque and current output torque of the vehicle; determining a torque decrease slope based on the first road adhesion coefficient, the second road adhesion coefficient, the required torque, and the current output torque; The entire vehicle is controlled to reduce the output torque at the torque reduction slope.

7. The method according to claim 6, characterized in that The determining of the torque reduction slope based on the first road adhesion coefficient, the second road adhesion coefficient, the required torque and the current output torque includes: determining an absolute value of a difference in a road surface adhesion coefficient based on the first road surface adhesion coefficient and the second road surface adhesion coefficient; determining an absolute value of a torque difference based on the required torque and the current output torque; The torque reduction slope is determined based on the absolute value of the difference in the road adhesion coefficient and the absolute value of the torque difference.

8. The method according to any one of claims 1 to 7, characterized in that: The determining a first speed difference threshold based on the first road surface adhesion coefficient and the second road surface adhesion coefficient includes: determining an absolute value of a difference in a road surface adhesion coefficient based on the first road surface adhesion coefficient and the second road surface adhesion coefficient; The first speed difference threshold is determined according to the absolute value of the difference, and the first speed difference threshold is negatively correlated with the absolute value of the difference.

9. The method according to claim 4, characterized in that The determining of the speed difference integral coefficient based on the first speed difference and the first speed difference change rate comprises: Obtaining a predetermined speed difference integral coefficient lookup table, wherein the speed difference integral coefficient lookup table includes a correlation relationship between a speed difference, a speed difference change rate, and a speed difference integral coefficient; The speed difference integral coefficient corresponding to the first speed difference and the first speed difference change rate is determined in the speed difference integral coefficient lookup table.

10. An adaptive control device for differential protection, characterized in that: The device comprises: A first acquisition unit is used to acquire a first wheel speed of a left wheel and a second wheel speed of a right wheel of the vehicle, as well as a first road adhesion coefficient of the left wheel and a second road adhesion coefficient of the right wheel; a first determining unit, configured to determine a first speed difference based on the first wheel speed and the second wheel speed; a second determining unit, configured to determine a first speed difference threshold based on the first road adhesion coefficient and the second road adhesion coefficient; A control unit is used to reduce the output torque of the entire vehicle when the first speed difference is greater than the first speed difference threshold so as to reduce the first speed difference.

11. An adaptive control device for differential protection, characterized in that: The device comprises: a memory and a processor; The memory is used to store relevant program codes; The processor is used to call the program code to execute the adaptive control method for differential protection according to any one of claims 1 to 9.

12. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store a computer program, and the computer program is used to execute the adaptive control method for differential protection according to any one of claims 1 to 9.

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