Vehicle control method and device, vehicle and storage medium

Abstract

A vehicle control method and device, vehicle and storage medium belong to the field of automobile technology, the method comprises: obtaining the wheel speed of two wheels on the first drive shaft of the vehicle, the first drive shaft is any drive shaft of the vehicle, the output torque of the first motor corresponding to the first drive shaft is the first torque; in the case where the first difference of the two wheels on the first drive shaft is greater than the first safety threshold, based on the slip rate of the two wheels on the first drive shaft, the output torque of the first motor is changed from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold, the first difference is the difference of the wheel speed or the slip rate, the first safety threshold is the safety threshold corresponding to the case where the output torque of the first motor is the first torque, and the second safety threshold is the safety threshold corresponding to the case where the output torque of the first motor is the second torque.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automobiles, and in particular to a vehicle control method and device, a vehicle, and a storage medium. BACKGROUND

[0002] A differential in a vehicle is a mechanism that outputs different torques to left and right drive half shafts in a drive shaft, so that two wheels on the same drive shaft rotate at different wheel speeds. The differential can meet the requirement of different wheel speeds of two wheels on the same drive shaft when the vehicle turns. In the scene of single-wheel slip such as high-speed cornering and off-road escape, the first difference of two wheels on the same drive shaft is prone to be too large, thereby causing damage to the differential.

[0003] To cope with this situation, the related technology provides a limited slip differential (LSD). The LSD includes an electric control execution unit and a clutch. When the vehicle is controlled, the electric control execution unit controls the state of the clutch, controls the degree of engagement of the left and right drive half shafts connected with the clutch in the drive shaft through the state of the clutch, and limits the first difference of two wheels on the same drive shaft.

[0004] Since the LSD needs to be controlled by the electric control execution unit, and the clutch of the LSD is worn out during the working process and has a low service life. Thus, the cost of using the LSD to control the differential is high. SUMMARY

[0005] The present application provides a vehicle control method and device, a vehicle, and a storage medium, so that the problem of the first difference being too large can be solved by using a common differential for the vehicle, and the cost is saved.

[0006] In a first aspect, the present application provides a vehicle control method, which includes: obtaining wheel speeds of two wheels on a first drive shaft of a vehicle, and an output torque of a first motor corresponding to the first drive shaft being a first torque; in a case where a first difference of the two wheels on the first drive shaft of the vehicle is greater than a first safety threshold, controlling the output torque of the first motor to change from the first torque to a second torque based on a slip rate of the two wheels on the first drive shaft, so that the first difference of the two wheels on the first drive shaft is not greater than a second safety threshold.

[0007] The first drive shaft can be any drive shaft of the vehicle. For example, the first drive shaft can be a front drive shaft of the vehicle, and the method is applied to the front drive shaft to control the first difference between the two wheels on the front drive shaft within the safety threshold. For another example, the first drive shaft can be a rear drive shaft of the vehicle, and the method is applied to the rear drive shaft to control the first difference between the two wheels on the rear drive shaft within the safety threshold. For another example, the first drive shaft can be both a front drive shaft and a rear drive shaft of the vehicle, and the method is applied to the front drive shaft and the rear drive shaft to control the first difference between the two wheels on the rear drive shaft within the safety threshold.

[0008] For example, the drive shaft and the motor to which the method is applied can be determined according to the configuration of the motor and the clutch, for example, the method is applied to the drive shaft and the motor configured with an open differential.

[0009] The first difference can be a wheel speed difference or a slip ratio difference. The wheel speed difference between the two wheels on the first drive shaft of the vehicle can be obtained by subtracting the wheel speeds of the two wheels and taking the absolute value. The slip ratio difference between the two wheels on the first drive shaft of the vehicle can be obtained by subtracting the slip ratios of the two wheels and taking the absolute value. Generally, the greater the slip ratio difference, the greater the wheel speed difference.

[0010] The first drive shaft corresponds to a first motor, and the output torque of the first motor is different, and the safety threshold is also different. The first safety threshold is the safety threshold corresponding to the case that the output torque of the first motor is the first torque, and the second safety threshold is the safety threshold corresponding to the case that the output torque of the first motor is the second torque.

[0011] For the vehicle, the first difference between the two wheels on the first drive shaft is usually in the scene of high-speed cornering (drifting), off-road escape, etc. In this case, by adjusting the size of the output torque of the first motor, the first difference and the safety threshold can be changed, so that the first difference between the two wheels on the first drive shaft is not greater than the safety threshold. Through the above vehicle control scheme, the vehicle only needs to use a common differential to solve the problem of excessive differential, and the scheme can delay the life of the differential, thereby controlling the cost.

[0012] Optionally, the method can further include determining the first safety threshold. The safety threshold here refers to the wheel speed difference (or slip ratio) range that can ensure the safe operation of the differential under the output torque of the first motor.

[0013] Since the motor output torque and the threshold are negatively related, determining the first safety threshold includes:

[0014] Obtaining a corresponding relationship between the motor output torque and the threshold; and obtaining the first safety threshold corresponding to the case that the output torque of the first motor is the first torque from the corresponding relationship between the motor output torque and the threshold.

[0015] In this way, the safety threshold corresponding to the first torque of the current vehicle can be obtained in real time, which provides a basis for controlling the output torque of the motor, avoids the first difference exceeding the safety threshold, and ensures safety.

[0016] The motor output torque and the threshold value can be obtained through bench durability testing of the vehicle. For example, the wheel speed difference or the slip ratio difference of the two wheels is controlled to change from small to large under a certain output torque, and the critical values of the undamaged differential and the damaged differential are determined, and the critical values are taken as the threshold value corresponding to the output torque. Alternatively, the output torque is controlled to change from small to large under a certain wheel speed difference or slip ratio difference, and the critical values of the undamaged differential and the damaged differential are determined, and the wheel speed difference or slip ratio difference is taken as the threshold value corresponding to the output torque. In this way, the threshold value corresponding to each output torque is determined to form a corresponding relationship.

[0017] The wheel speed difference or the slip ratio difference of the two wheels can be changed by applying different braking forces to the two wheels or adding different loads to the two wheels.

[0018] Correspondingly, the method for determining the second safety threshold is the same as the method for determining the first safety threshold, that is, the second safety threshold corresponding to the output torque of the first motor after dynamic control is obtained from the corresponding relationship between the motor output torque and the threshold value.

[0019] For the vehicle, the current scene of the vehicle can be identified through the slip ratio of the two wheels on the first drive shaft.

[0020] In the implementation manner of the present application, the current scene of the vehicle can be identified based on the relationship between the slip ratio of the wheel with smaller wheel speed of the two wheels on the first drive shaft and the slip ratio range, and then the output torque of the first motor is controlled based on the current scene of the vehicle.

[0021] The slip ratio range can be obtained through tire characteristic test. The adhesion of the tire and the slip ratio are in a quadratic function relationship, and the wheel has the best adhesion within the slip ratio range. The slip ratio range can be 10% to 25%.

[0022] For example, the slip ratio of the wheel with smaller wheel speed of the two wheels on the first drive shaft is lower than the lower limit of the slip ratio range, and one wheel of the first drive shaft does not slip at all, and it is determined that the vehicle is in a one-side wheel with good adhesion escape scene, such as an off-road escape scene.

[0023] For another example, when the slip ratio of the wheel with smaller wheel speed among the two wheels on the first drive axle is higher than the upper limit of the slip ratio range, and both of the two wheels on the first drive axle have slipped, it is determined that the vehicle is in a drift scenario where both sides of the vehicle lose adhesion, such as a high-speed cornering (drifting) scenario.

[0024] In different scenarios of the vehicle, the output torque of the motor is controlled differently to make the first difference between the two wheels on the first drive axle not greater than the second safety threshold.

[0025] Exemplarily, the second torque is greater than the first torque;

[0026] Based on the slip ratios of the two wheels on the first drive axle, the output torque of the first motor is controlled to change from the first torque to the second torque to make the first difference between the two wheels on the first drive axle not greater than the second safety threshold, comprising:

[0027] When the slip ratio of the wheel with smaller wheel speed among the two wheels on the first drive axle is lower than the lower limit of the slip ratio range, the wheel with greater wheel speed or slip ratio among the two wheels on the first drive axle is braked; the output torque of the first motor is controlled to increase from the first torque to the second torque to make the first difference between the two wheels on the first drive axle not greater than the second safety threshold.

[0028] In the escape scenario of the vehicle, it is necessary to increase the output torque of the first motor to make the vehicle obtain greater kinetic energy to escape. However, since the output torque of the motor and the safety threshold are in a negative correlation, increasing the output torque of the first motor will reduce the safety threshold, and increasing the output torque will also cause the first difference to increase, so only increasing the output torque cannot guarantee that the first difference between the two wheels is not greater than the second safety threshold while meeting the kinetic energy demand. Therefore, the implementation manner of the present application first brakes the wheel with greater wheel speed or slip ratio among the two wheels to reduce the first difference, and then increases the output torque to guarantee that the first difference between the two wheels on the first drive axle is not greater than the second safety threshold while increasing the output torque.

[0029] In this scenario, through the combination of braking and increasing the output torque, the kinetic energy demand of the vehicle in the scenario can be guaranteed, and the wheel speed difference can be guaranteed to be below the safety threshold, thereby guaranteeing the safety of the differential.

[0030] The braking of the wheel with greater wheel speed or slip ratio among the two wheels on the first drive axle; and the control of the output torque of the first motor to increase from the first torque to the second torque to make the first difference between the two wheels on the first drive axle not greater than the second safety threshold can comprise:

[0031] The target difference after braking is determined, and the target difference after braking is less than the first safety threshold, for example, less than the first safety threshold by a certain value, such as less than 20% of the first safety threshold; the braking force is provided according to the target difference, and the wheel with a larger wheel speed or slip rate of the two wheels is braked; after the braking makes the first difference of the two wheels reach the target difference, the output torque of the first motor is controlled to increase from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

[0032] In one way, the control of the first motor to increase the output torque can be in a step-by-step manner until the first difference of the two wheels on the first drive shaft is equal to the second safety threshold, or until the first difference of the two wheels on the first drive shaft is less than the second safety threshold, and the difference is smaller, such as 1-5%.

[0033] In another way, the control of the first motor to increase the output torque can first determine the second torque corresponding to the first difference of the two wheels, and the safety threshold corresponding to the second torque is greater than the first difference of the two wheels. Since the first difference of the two wheels will increase as the torque increases, when determining the second torque, a margin can be reserved. For example, the maximum safe output torque is determined according to the first difference after braking, and then a certain amount or percentage (such as 10%) is reduced as the second torque on this basis, which is used to ensure that the first difference will not exceed the safety threshold after the output torque is increased.

[0034] Exemplarily, the second torque is less than the first torque;

[0035] Based on the slip rate of the two wheels on the first drive shaft, the output torque of the first motor is controlled to change from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold, comprising:

[0036] The first way: in the case that the slip rate of the wheel with a smaller wheel speed of the two wheels on the first drive shaft is higher than the upper limit of the slip rate range, the output torque of the first motor is controlled to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

[0037] The second way: in the case that the slip rate of the wheel with a smaller wheel speed of the two wheels on the first drive shaft is higher than the upper limit of the slip rate range, the wheel with a larger wheel speed or slip rate of the two wheels on the first drive shaft is braked; the output torque of the first motor is controlled to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

[0038] In the case that the vehicle is in high-speed cornering (drifting), since the output torque of the motor and the safety threshold are in a negative correlation, reducing the output torque of the first motor increases the safety threshold, and reducing the output torque also reduces the first difference. Therefore, the first difference of the two wheels on the first drive shaft can be not greater than the second safety threshold by reducing the output torque of the first motor. In addition to reducing the output torque to make the first difference of the two wheels on the first drive shaft not greater than the second safety threshold, the output torque can be reduced and braking can be combined to make the first difference of the two wheels on the first drive shaft not greater than the second safety threshold.

[0039] In this scenario, the drifting of the vehicle can be reduced by controlling the output torque of the motor, and the wheel speed difference can be ensured to be below the safety threshold by reducing the output torque or by reducing the output torque and braking, thereby ensuring the safety of the differential.

[0040] In the first mode described above, the method of reducing the output torque of the motor can be stepwise. The method of reducing the output torque of the motor can also determine a second torque corresponding to the first difference of the two wheels, the second torque being a safety output torque, and the motor is controlled using the second torque. The safety threshold corresponding to the second torque can be greater than or equal to the first difference of the two wheels, so as to ensure that the first difference is less than the safety threshold; or the safety threshold corresponding to the second torque can be less than the first difference of the two wheels, and since the first difference of the two wheels decreases as the torque decreases, the safety threshold can be slightly less than the first difference of the two wheels (for example, 5%), and the first difference can also be ensured to be less than the safety threshold.

[0041] In the second mode described above, the target difference after braking can be determined first; braking force is provided according to the first difference to brake the wheel with a larger wheel speed or slip rate among the two wheels; and after the braking makes the first difference of the two wheels reach the target difference, the output torque of the first motor is controlled to decrease from the first torque to the second torque, so as to make the first difference of the two wheels on the first drive shaft not greater than the second safety threshold.

[0042] In one mode, the target difference after braking is less than the first safety threshold, and subsequent continuous reduction of the output torque can ensure that the first difference of the two wheels is not greater than the second safety threshold. In another mode, the target difference after braking can also be not less than the first safety threshold, or even not less than the second safety threshold, and the two modes are combined by subsequent continuous reduction of the output torque, so as to make the first difference of the two wheels not greater than the second safety threshold.

[0043] In the implementation mode of the present application, the control of the output torque of the first motor can be realized by a control instruction.

[0044] Exemplarily, the output torque of the first motor is controlled from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold, comprising:

[0045] The second torque is determined according to the first difference of the two wheels on the first drive shaft; a control instruction is output based on the second torque; and the output torque of the first motor is controlled by using the control instruction, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

[0046] Here, the first difference used to determine the second torque is the first difference of the two wheels without braking if no braking is performed, or the first difference of the two wheels after braking if braking is performed.

[0047] In the case of increasing the output torque, the maximum safe output torque is determined according to the first difference after braking, and then a certain amount or percentage (such as 10%) is reduced on this basis as the second torque.

[0048] In the case of reducing the output torque, the safety threshold corresponding to the second torque can be greater than or equal to the first difference of the two wheels; the safety threshold corresponding to the second torque can also be less than the first difference of the two wheels, such as slightly less (for example, 5%) than the first difference of the two wheels.

[0049] For a front- or rear-drive vehicle, only the motor of the first drive shaft can be controlled.

[0050] For a four-wheel drive vehicle, the second drive shaft can also be controlled when the first drive shaft is controlled. For example:

[0051] In the case where the slip rate of the wheel with a smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip rate range, and the slip rate of the wheel with a smaller wheel speed among the two wheels on the second drive shaft of the vehicle is not higher than the upper limit of the slip rate range, the output torque of the second motor corresponding to the second drive shaft of the vehicle is controlled from the third torque to the fourth torque, and the first difference of the two wheels on the second drive shaft is not greater than the third safety threshold, which is the safety threshold corresponding to the case where the output torque of the second motor is the fourth torque.

[0052] For a four-wheel drive vehicle, when the slip rate of the wheel with a smaller wheel speed of the other drive shaft does not exceed the upper limit, torque transfer can be performed to ensure the overall driving force of the vehicle.

[0053] Here, the output torque control of the second motor can be stepwise or the safety output torque corresponding to the first difference of the two wheels on the second drive shaft can be determined and then controlled. The detailed process can be referred to the control of the first motor described above.

[0054] In the case that the slip ratio of the wheel with smaller wheel speed among the two wheels on the second drive axle is higher than the upper limit of the slip ratio range, the second motor corresponding to the second drive axle is controlled to reduce the output torque, and the detailed process can be referred to the control of the first motor.

[0055] In the implementation of the present application, the slip ratio is the proportion of the sliding component in the wheel movement, and the slip ratio is the ratio of the difference between the vehicle speed and the wheel speed to the vehicle speed. The vehicle speed and the wheel speed can be the average vehicle speed and the average wheel speed, such as the average vehicle speed and the average wheel speed in a period of time.

[0056] In some possible implementations of the present application, the slip ratios of the two wheels on the first drive axle are obtained according to the wheel speeds of the two wheels and the rotational speed of the first motor.

[0057] The wheel speed of the wheel is usually collected by a wheel speed sensor and then reported by a brake control unit. When the wheel speed sensor fails, the wheel speed of the wheel is inaccurate and the slip ratio cannot be calculated correctly. Therefore, the slip ratios of the two wheels on the first drive axle are determined, comprising:

[0058] obtaining the rotational speed of the first motor; determining whether the wheel speed is accurate according to the rotational speed of the first motor and the wheel speeds of the two wheels on the first drive axle; in the case that the wheel speeds of the two wheels on the first drive axle are accurate, determining the slip ratios of the two wheels on the first drive axle based on the wheel speeds of the two wheels on the first drive axle and the rotational speed of the first motor. In the case that the wheel speeds of the two wheels on the first drive axle are inaccurate, outputting a fault prompt to prompt that the wheel speed sensor needs to be repaired or replaced.

[0059] In this implementation, the slip ratio of the wheel is calculated again in the case that the wheel speed is determined to be accurate, thereby ensuring the accuracy of the calculated slip ratio.

[0060] The wheel speeds of the two wheels on the first drive axle are determined to be accurate according to the wheel speeds of the two wheels on the first drive axle and the rotational speed of the first motor, for example, the rotational speed of the motor and the average of the wheel speeds of the two wheels are compared, if the difference is greater than a set difference, the wheel speed is considered to be inaccurate, otherwise the wheel speed is considered to be accurate.

[0061] When the slip ratio is calculated according to the wheel speeds of the two wheels and the rotational speed of the first motor, the vehicle speed can be calculated according to the rotational speed of the first motor first, and then the slip ratios of the two wheels are calculated based on the vehicle speed and the wheel speeds of the two wheels.

[0062] In other possible implementations, the vehicle speed can also be obtained additionally, and the slip ratios of the two wheels are calculated according to the vehicle speed and the wheel speeds of the two wheels.

[0063] In other possible implementation manners, the acceleration of the vehicle can also be additionally acquired, the vehicle speed is determined by integrating the acceleration of the vehicle, and the slip rates of the two wheels are calculated according to the vehicle speed and the wheel speeds of the two wheels.

[0064] In some possible implementation manners of the present application, the method is executed by the vehicle control unit. For example, the vehicle control unit controls the output torque of the first motor, or controls the single-wheel brake and the output torque of the first motor.

[0065] When the vehicle control unit executes the method, the wheel speeds of the two wheels on the first drive axle are acquired, including: acquiring the wheel speeds of the two wheels on the first drive axle output by the brake control unit of the vehicle. The rotational speed of the first motor is acquired, including: acquiring the rotational speed of the first motor output by the motor controller of the vehicle.

[0066] In some possible implementation manners of the present application, the method is executed by the motor controller. For example, the vehicle control unit controls the output torque of the first motor, or controls the single-wheel brake and the output torque of the first motor.

[0067] When the motor controller executes the method, the wheel speeds of the two wheels on the first drive axle are acquired, including: acquiring the wheel speeds of the two wheels on the first drive axle output by the brake control unit of the vehicle. The rotational speed of the first motor is acquired, including: acquiring the rotational speed detected by the sensor in the first motor.

[0068] In this implementation manner, either the vehicle control unit or the motor controller can be used as the execution subject, and any controller can be used for control according to actual conditions, so as to realize the differential protection scheme, which is beneficial to integrated control and arrangement in actual application.

[0069] In a second aspect, the present application provides a vehicle control device, which comprises:

[0070] An acquisition unit is configured to acquire wheel speeds of two wheels on a first drive axle of a vehicle, the first drive axle being any drive axle of the vehicle, and an output torque of a first motor corresponding to the first drive axle being a first torque;

[0071] A control unit is configured to, in a case where a first difference of the two wheels on the first drive axle is greater than a first safety threshold, control the output torque of the first motor to change from the first torque to a second torque based on slip rates of the two wheels on the first drive axle, so that the first difference of the two wheels on the first drive axle is not greater than a second safety threshold, the first difference being a wheel speed difference or a slip rate difference, the first safety threshold being a safety threshold corresponding to a case where the output torque of the first motor is the first torque, and the second safety threshold being a safety threshold corresponding to a case where the output torque of the first motor is the second torque.

[0072] Optionally, the second torque is greater than the first torque.

[0073] The control unit is configured to, in a case where the slip ratio of the wheel with the smaller wheel speed among the two wheels on the first drive shaft is lower than the lower limit of the slip ratio range, brake the wheel with the larger wheel speed or slip ratio among the two wheels on the first drive shaft; and control the output torque of the first motor to increase from the first torque to the second torque, so that the first difference between the two wheels on the first drive shaft is not greater than the second safety threshold.

[0074] Optionally, the second torque is less than the first torque.

[0075] The control unit is configured to, in a case where the slip ratio of the wheel with the smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip ratio range, control the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference between the two wheels on the first drive shaft is not greater than the second safety threshold.

[0076] Optionally, the second torque is less than the first torque.

[0077] The control unit is configured to, in a case where the slip ratio of the wheel with the smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip ratio range, brake the wheel with the larger wheel speed or slip ratio among the two wheels on the first drive shaft; and control the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference between the two wheels on the first drive shaft is not greater than the second safety threshold.

[0078] Optionally, the control unit is configured to determine the second torque according to the first difference between the two wheels on the first drive shaft; output a control instruction based on the second torque; and control the output torque of the first motor by using the control instruction, so that the first difference between the two wheels on the first drive shaft is not greater than the second safety threshold.

[0079] Optionally, the control unit is further configured to, in a case where the slip ratio of the wheel with the smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip ratio range and the slip ratio of the wheel with the smaller wheel speed among the two wheels on the second drive shaft of the vehicle is not higher than the upper limit of the slip ratio range, control the output torque of the second motor corresponding to the second drive shaft of the vehicle to increase from a third torque to a fourth torque, and make the first difference between the two wheels on the second drive shaft not greater than a third safety threshold, the third safety threshold being a safety threshold corresponding to the case where the output torque of the second motor is the fourth torque.

[0080] Optionally, the acquisition unit is further configured to acquire the rotational speed of the first motor.

[0081] The device further comprises a determination unit configured to determine whether the wheel speeds are accurate according to the rotation speed of the first motor and the wheel speeds of the two wheels on the first drive shaft; and determine the slip rates of the two wheels on the first drive shaft based on the wheel speeds of the two wheels on the first drive shaft and the rotation speed of the first motor, in a case where the wheel speeds of the two wheels on the first drive shaft are accurate.

[0082] Optionally, the device comprises a vehicle control unit, or the device comprises a motor controller.

[0083] Optionally, the obtaining unit is further configured to obtain a corresponding relationship between the motor output torque and the threshold value, the motor output torque and the threshold value being negatively correlated; and obtain the first safety threshold value corresponding to a case where the output torque of the first motor is the first torque from the corresponding relationship between the motor output torque and the threshold value.

[0084] In a third aspect, the present application provides a vehicle, comprising the vehicle control device and the motor, and the vehicle control device is connected with the motor.

[0085] In a fourth aspect, the present application provides a vehicle control device, comprising a processor and a memory; the memory is configured to store a software program and a module; the processor, by running or executing the software program and / or the module stored in the memory, causes the vehicle control device to implement the method in any possible implementation manner of the first aspect.

[0086] Optionally, the processor is one or more, and the memory is one or more.

[0087] Optionally, the memory can be integrated with the processor, or the memory and the processor are separately arranged.

[0088] In the process of implementation, the memory can be a non-transitory memory, for example, a read only memory (ROM), which can be integrated on the same chip with the processor, or can be arranged on different chips respectively, and the type of the memory and the arrangement mode of the memory and the processor are not limited in the embodiments of the present application.

[0089] In a fifth aspect, the present application provides a computer program (product), comprising computer program code, when the computer program code is run by a computer, causing the computer to execute the method in any possible implementation manner of the first aspect.

[0090] In a sixth aspect, the present application provides a computer readable storage medium for storing program codes executed by a processor, the program codes comprising the method in any possible implementation of the first aspect.

[0091] In a seventh aspect, a chip is provided, comprising a processor configured to invoke and run instructions stored in a memory, so that a communication device installed with the chip executes the method in any possible implementation of the first aspect.

[0092] In an eighth aspect, another chip is provided, comprising an input interface, an output interface, a processor and a memory, the input interface, the output interface, the processor and the memory are connected through internal connection paths, the processor is configured to execute codes in the memory, when the codes are executed, the processor is configured to execute the method in any possible implementation of the first aspect. BRIEF DESCRIPTION OF DRAWINGS

[0093] Figure 1 is a schematic diagram of an architecture of a vehicle provided by an embodiment of the present application;

[0094] Figure 2 is a flowchart of a vehicle control method provided by an embodiment of the present application;

[0095] Figure 3 is a flowchart of a vehicle control method provided by an embodiment of the present application;

[0096] Figure 4 is a schematic diagram of a relationship between a threshold value and an output torque provided by an embodiment of the present application;

[0097] Figure 5 is a flowchart of a vehicle control method provided by an embodiment of the present application;

[0098] Figure 6 is a block diagram of a vehicle control device provided by an embodiment of the present application;

[0099] Figure 7 is a schematic diagram of a structure of a vehicle control device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0100] In order to make the purpose, technical scheme and advantages of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the drawings.

[0101] In order to make the purpose, technical scheme and advantages of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the drawings. Figure 1is a schematic diagram of an architecture of a vehicle provided by an embodiment of the present application. Referring to Figure 1 The vehicle includes a motor control loop and a brake control loop.

[0102] The motor control loop mainly includes a vehicle control unit (VCU) 1, a front motor controller 2, a rear motor controller 3, a front motor 4, and a rear motor 5. The vehicle control unit 1 is a master control unit of the vehicle, receives motor speed and torque signals of the motor controller, and controls the motor controller to increase or decrease the torque demand. The front motor controller 2 and the rear motor controller 3 respectively control the front motor 4 and the rear motor 5 to increase or decrease the torque according to the torque request / instruction of the vehicle control unit 1, and detect the actual speed and torque signals of the front and rear motors and feed back the signals to the vehicle control unit 1.

[0103] The brake control loop includes the vehicle control unit 1, a brake control unit 6, a right front wheel speed sensor 7, a right rear wheel speed sensor 8, a left front wheel speed sensor 9, a left rear wheel speed sensor 10, a right front wheel brake device 11, a right rear wheel brake device 12, a left front wheel brake device 13, and a left rear wheel brake device 14. The vehicle control unit 1 receives wheel speed signals and brake pressure signals of the brake control unit, and controls the pressure building of the brake loop. The brake control unit 6 mainly controls the pressure building, pressure maintaining, and pressure reducing of the brake loop, so as to accurately control the wheel brake pressure and realize the differential control function.

[0104] Of course, Figure 1 is only an example, and in other implementations, Figure 1 The front motor and the front motor controller, and the rear motor and the rear motor controller in the above embodiment can only have one set.

[0105] Figure 2 is a flowchart of a vehicle control method provided by an embodiment of the present application. The method can be executed by a vehicle control unit or a motor controller of a vehicle. As shown in Figure 2 The method includes the following steps:

[0106] 101: Obtain wheel speeds of two wheels on a first drive shaft of a vehicle, and an output torque of a first motor corresponding to the first drive shaft is a first torque.

[0107] The first drive shaft can be any drive shaft of the vehicle. For example, the first drive shaft can be a front drive shaft of the vehicle, and the method is applied to the front drive shaft to control the first difference between the two wheels on the front drive shaft within the safety threshold. For another example, the first drive shaft can be a rear drive shaft of the vehicle, and the method is applied to the rear drive shaft to control the first difference between the two wheels on the rear drive shaft within the safety threshold. For another example, the first drive shaft can be both a front drive shaft and a rear drive shaft of the vehicle, and the method is applied to the front drive shaft and the rear drive shaft to control the first difference between the two wheels on the rear drive shaft within the safety threshold.

[0108] For example, the drive shaft and the motor to which the method is applied can be determined according to the configuration of the motor and the clutch, for example, the method is applied to the drive shaft and the motor configured with an open differential.

[0109] 102: In a case where the first difference between the two wheels on the first drive shaft of the vehicle is greater than the first safety threshold, the output torque of the first motor is controlled to change from the first torque to the second torque based on the slip rates of the two wheels on the first drive shaft, so that the first difference between the two wheels on the first drive shaft is not greater than the second safety threshold.

[0110] The first difference can be a wheel speed difference or a slip rate difference. The wheel speed difference between the two wheels on the first drive shaft of the vehicle can be obtained by subtracting the wheel speeds of the two wheels and taking an absolute value. The slip rate difference between the two wheels on the first drive shaft of the vehicle can be obtained by subtracting the slip rates of the two wheels and taking an absolute value. Generally, the greater the slip rate difference, the greater the wheel speed difference.

[0111] The safety threshold is different for the first motor with different output torques. The first safety threshold is the safety threshold corresponding to the first motor with the first torque, and the second safety threshold is the safety threshold corresponding to the first motor with the second torque.

[0112] For the vehicle, the first difference between the two wheels on the first drive shaft is usually in the scene of high-speed cornering (drifting), off-road escape, etc. In this case, by adjusting the size of the output torque of the first motor, the first difference and the safety threshold can be changed, so that the first difference between the two wheels on the first drive shaft is not greater than the safety threshold. Through the above vehicle control scheme, the vehicle only needs to use a common differential to solve the problem of excessive differential, and the scheme can delay the life of the differential, thereby controlling the cost.

[0113] Figure 3is a flowchart of a vehicle control method provided by an embodiment of the present application. The method can be executed by a vehicle control unit or a motor controller of a vehicle. Taking the execution by the vehicle control unit as an example, when the vehicle control unit controls, the motor controller and the brake control unit control cooperatively, as shown in Figure 3 The method comprises the following steps:

[0114] 201: Obtain wheel speeds of two wheels on a first drive axle and a rotation speed of a first motor, and an output torque of the first motor corresponding to the first drive axle is a first torque.

[0115] The vehicle control unit obtains wheel speeds of two wheels on a first drive axle output by a brake control unit of the vehicle, and obtains a rotation speed of a first motor output by a motor controller of the vehicle.

[0116] Optionally, the method can further comprise: obtaining braking forces of the wheels, for example, monitoring the braking forces of the wheels by a brake pressure sensor, to provide a basis for subsequent single-wheel braking of the wheels.

[0117] 202: Determine whether the wheel speeds of the two wheels on the first drive axle are accurate according to the wheel speeds of the two wheels on the first drive axle and the rotation speed of the first motor. If the wheel speeds of the two wheels on the first drive axle are accurate, execute step 204; otherwise, execute step 203.

[0118] The wheel speeds of the wheels are usually collected by wheel speed sensors (or differential rotation speed sensors), for example, 4 wheel speed sensors in Figure 1 , and then reported to the vehicle control unit by the brake control unit. When the wheel speed sensors (or differential rotation speed sensors) are faulty, the wheel speeds of the wheels are inaccurate.

[0119] For example, compare the rotation speed of the motor with the average of the two wheel speeds, and if the difference is greater than a set difference, it is considered that the wheel speeds are inaccurate, otherwise, it is considered that the wheel speeds are accurate.

[0120] 203: Output a fault prompt to prompt that the wheel speed sensors need to be overhauled or replaced.

[0121] Step 203 is an optional step.

[0122] 204: Determine the slip rates of the two wheels on the first drive axle based on the wheel speeds of the two wheels on the first drive axle and the rotation speed of the first motor.

[0123] The slip rate is the proportion of the sliding component in the wheel motion, and the slip rate is the ratio of the difference between the vehicle speed and the wheel speed to the vehicle speed. The vehicle speed and the wheel speed can be average vehicle speed and average wheel speed, for example, average vehicle speed and average wheel speed in a period of time.

[0124] In some possible implementations of this application, the slip ratio of the two wheels on the first drive shaft is obtained based on the wheel speeds of the two wheels and the rotational speed of the first motor. When calculating the slip ratio based on the wheel speeds of the two wheels and the rotational speed of the first motor, the vehicle speed can be calculated first based on the rotational speed of the first motor, and then the slip ratio of the two wheels can be calculated based on the vehicle speed and the wheel speeds of the two wheels.

[0125] In this case, it is not necessary to use the vehicle's actual speed, which reduces the amount of parameters required and lowers the complexity.

[0126] In other possible implementations, the vehicle speed can also be obtained, and the slip ratio of the two wheels can be calculated based on the vehicle speed and the wheel speeds of the two wheels.

[0127] In other possible implementations, the vehicle's acceleration can be obtained additionally, the vehicle speed can be determined by integrating the vehicle's acceleration, and the slip ratio of the two wheels can be calculated based on the vehicle speed and the wheel speeds of the two wheels.

[0128] 205: Obtain the first safety threshold corresponding to the first motor output torque when the first torque is the first torque from the correspondence between the motor output torque and the threshold.

[0129] In this step, the vehicle control unit first obtains the output torque of the first motor. This output torque is sent to the vehicle control unit by the motor controller connected to the first motor, for example... Figure 1 The front motor controller in the system can send the output torque of the front motor to the vehicle control unit. The vehicle control unit, based on the correspondence between the motor output torque and a threshold, obtains the first safety threshold corresponding to the condition that the output torque of the first motor is a first torque. The motor output torque and the threshold are negatively correlated. This correspondence can be stored in the vehicle control unit or other devices in the vehicle with storage capabilities.

[0130] The motor output torque and threshold values ​​can be obtained through vehicle bench durability testing. For example, under a certain output torque, the wheel speed difference or slip ratio difference between the two wheels is controlled to increase from small to large to determine the critical values ​​for an undamaged differential and a damaged differential. These critical values ​​are then used as the threshold values ​​corresponding to that output torque. Alternatively, under a certain wheel speed difference or slip ratio difference, the output torque is controlled to increase from small to large to determine the critical values ​​for an undamaged differential and a damaged differential. These critical values ​​are then used as the output torque, and the wheel speed difference or slip ratio difference is used as the corresponding threshold value. In this way, the threshold values ​​corresponding to each output torque are determined, establishing a correspondence.

[0131] The control of the wheel speed difference or slip ratio difference between the two wheels from small to large can be achieved by applying different braking forces to the two wheels or by adding different loads to the two wheels.

[0132] 206: Determine whether the first difference of the two wheels on the first drive axle of the vehicle is greater than a first safety threshold. If the first difference of the two wheels on the first drive axle is greater than the first safety threshold, perform step 207.

[0133] For example, determine whether the wheel speed difference of the two wheels on the first drive axle of the vehicle is greater than a first safety threshold. The vehicle control unit subtracts the wheel speed of the two wheels belonging to the same drive axle after receiving the wheel speed of each wheel, and obtains the wheel speed difference of the two wheels on the first drive axle.

[0134] For another example, determine whether the slip ratio difference of the two wheels on the first drive axle of the vehicle is greater than a first safety threshold, and the safety threshold corresponding to the wheel speed difference and the safety threshold corresponding to the slip ratio difference are different.

[0135] Otherwise, the subsequent steps can not be performed, and the output torque of the first motor is maintained.

[0136] 207: Brake the wheel with higher wheel speed or slip ratio among the two wheels on the first drive axle.

[0137] Wherein, the determined braking force should be greater than the braking force monitored from the wheel with higher current wheel speed or slip ratio.

[0138] Wherein, braking the wheel means performing wheel-side hydraulic braking on the wheel, for example, providing brake pressure to the wheel brake device (such as brake pump) in the brake circuit to realize braking.

[0139] In one possible implementation, the vehicle control unit determines a target difference after braking, and the target difference after braking is less than the first safety threshold, for example, less than the first safety threshold by a certain value, such as less than the first safety threshold by more than 20%; and provides the braking force according to the target difference to brake the wheel with higher wheel speed or slip ratio among the two wheels.

[0140] Wherein, for the two wheels on the first drive axle, the wheel with lower wheel speed is the first wheel, and the wheel with higher wheel speed is the second wheel. When braking, the target wheel speed of the second wheel is determined according to the wheel speed of the first wheel, which can make the wheel speed difference between the first wheel and the second wheel reach the target difference. Then, the wheel speed to be reduced by braking is determined according to the target wheel speed and the current wheel speed of the second wheel, and then the corresponding braking force is determined according to the wheel speed to be reduced by braking.

[0141] The braking force and the reduced wheel speed have a mapping relationship, which can be obtained through bench test of the vehicle, and will not be described here.

[0142] After braking the wheels so that the first difference of the two wheels is not greater than the first safety threshold, stop braking the wheel with higher wheel speed or slip ratio among the two wheels on the first drive axle.

[0143] In another possible implementation, the vehicle control unit determines the target difference after braking, the target difference after braking is greater than the first safety threshold, but the difference between the target difference and the first safety threshold is reduced relative to the difference between the first difference and the first safety threshold.

[0144] After braking the wheels for a period of time, the braking of the wheel with greater wheel speed or slip ratio among the two wheels on the first drive shaft is stopped, and at the time of stopping the braking, the first difference between the two wheels is still greater than the first safety threshold, but the difference between the first difference and the first safety threshold is reduced.

[0145] Optionally, step 207 can also be executed after step 208 and step 210.

[0146] 208: Determine whether the slip ratio of the wheel with smaller wheel speed among the two wheels on the first drive shaft is higher than the lower limit of the slip ratio range. If the slip ratio of the wheel with smaller wheel speed among the two wheels on the first drive shaft is lower than the lower limit of the slip ratio range, step 209 is executed. Otherwise, step 210 is executed.

[0147] Here, when determining whether the slip ratio of the wheel with smaller wheel speed among the two wheels is higher than the lower limit of the slip ratio range, it can be whether the slip ratio before braking is higher than the lower limit of the slip ratio range, or whether the slip ratio after braking is higher than the lower limit of the slip ratio range. Since step 207 is to brake the wheel with greater wheel speed, and the slip ratio of the wheel with smaller wheel speed is not significantly affected by the braking, the slip ratio of the wheel with smaller wheel speed among the two wheels before braking and the slip ratio after braking do not change or change little.

[0148] Based on the relationship between the slip ratio of the wheel with smaller wheel speed among the two wheels on the first drive shaft and the slip ratio range, the current scene of the vehicle is identified, and then the output torque of the first motor is controlled based on the current scene of the vehicle.

[0149] The slip ratio range can be obtained through a tire characteristic test, and the adhesion of the tire and the slip ratio are in a quadratic function relationship, and within the slip ratio range, the wheel has the best adhesion. The slip ratio range can be 10% to 25%.

[0150] When the slip ratio of the wheel with smaller wheel speed among the two wheels on the first drive shaft is lower than the lower limit of the slip ratio range, it is determined that the vehicle is in a one-side wheel with good adhesion escape scene, such as an off-road escape scene.

[0151] 209: Control the output torque of the first motor to increase from the first torque to the second torque, so that the first difference between the two wheels on the first drive shaft is not greater than the second safety threshold.

[0152] The second safety threshold is a safety threshold corresponding to the second torque of the first motor.

[0153] After the braking makes the first difference of the two wheels reach the target difference, the output torque of the first motor is controlled to increase from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

[0154] In one way, the control of the first motor to increase the output torque can be in a step-by-step manner until the first difference of the two wheels on the first drive shaft is equal to the second safety threshold, or until the first difference of the two wheels on the first drive shaft is less than the second safety threshold, and the difference is smaller, such as 1-5%.

[0155] When performing step-by-step control, each time the output torque is increased by one unit based on the last output torque, and after the control is completed, it is determined whether the first difference of the two wheels is greater than the second safety threshold. The above process is repeated until the first difference of the two wheels is not greater than the second safety threshold. Wherein, the unit of each increase is determined according to the control accuracy of the motor.

[0156] In another way, the control of the first motor to increase the output torque can first determine the second torque corresponding to the first difference of the two wheels, and the safety threshold corresponding to the second torque is greater than the first difference of the two wheels. Since the first difference of the two wheels will increase as the torque increases, when determining the second torque, a margin can be reserved. For example, according to the first difference after braking, the maximum safe output torque is determined, and then a certain amount or percentage (such as 10%) is reduced as the second torque, which is used to ensure that the first difference will not exceed the safety threshold after the output torque is increased.

[0157] Figure 4 The corresponding relationship between torque and threshold is shown, and the torque and the threshold are negatively related. As shown in Figure 4 Before step 208 is performed, the output torque of the first motor is a, and the corresponding first safety threshold is A; after braking, the wheel speed difference of the two wheels on the first drive shaft is reduced to C, at this time the torque value cannot be directly selected as the output torque c corresponding to the threshold value C, but a smaller output torque b than c is selected, to ensure that the first difference will not exceed the second safety threshold B corresponding to b after the output torque is increased to b.

[0158] That is, the second torque is determined according to the first difference of the two wheels on the first drive shaft; the first control instruction is output based on the second torque; and the output torque of the first motor is controlled to increase from the first torque to the second torque by using the first control instruction.

[0159] In the vehicle is in the escape scene, it is needed to increase the output torque of the first motor, so that the vehicle obtains greater kinetic energy to escape. But because the output torque of the motor and the safety threshold are in a negative correlation, increasing the output torque of the first motor makes the safety threshold decrease, and increasing the output torque also causes the first difference to increase, so only increasing the output torque cannot guarantee that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold while meeting the kinetic energy demand. Therefore, the implementation manner of the present application first brakes the wheel with greater wheel speed or slip rate among the two wheels, so that the first difference decreases, and then increases the output torque, so as to guarantee that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold while increasing the output torque.

[0160] In this scenario, through the combination of braking and increasing the output torque, the kinetic energy demand of the vehicle in the scenario can be guaranteed, and the wheel speed difference can be guaranteed to be below the safety threshold, so as to guarantee the safety of the differential.

[0161] Among them, the torque increment formed by increasing the torque is used to compensate for the power loss caused by unilateral braking, and the increment is positively correlated with the single-wheel braking pressure in addition to being limited by the first difference. That is, in addition to guaranteeing that the first difference does not exceed the safety threshold, the greater the single-wheel braking pressure, the greater the torque increment can be selected.

[0162] 210: Determine whether the slip rate of the wheel with smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip rate range. If the slip rate of the wheel with smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip rate range, step 211 is performed. Otherwise, the output torque of the first motor is maintained.

[0163] Here, when determining whether the slip rate of the wheel with smaller wheel speed among the two wheels is higher than the upper limit of the slip rate range, it can be whether the slip rate before braking is higher than the upper limit of the slip rate range, or whether the slip rate after braking is higher than the upper limit of the slip rate range.

[0164] When the slip rate of the wheel with smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip rate range, it is determined that the vehicle is in a drift scenario in which both sides of the wheel lose adhesion, such as a high-speed cornering (drift) scenario.

[0165] 211: Control the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

[0166] After braking makes the first difference of the two wheels reach the target difference, the output torque of the first motor is controlled to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

[0167] determining a second torque according to the first difference of the two wheels on the first drive shaft; outputting a second control instruction based on the second torque; and controlling the first motor to increase or decrease the torque using the second control instruction.

[0168] In one way, the target difference after braking is less than the first safety threshold, and subsequent continuous reduction of the output torque can ensure that the first difference of the two wheels is not greater than the second safety threshold. In another way, the target difference after braking can also be not less than the first safety threshold, and even not less than the subsequent second safety threshold. Through the combination of the two ways, the first difference of the two wheels is not greater than the second safety threshold.

[0169] In the case that the slip rate of the wheel with smaller wheel speed among the two wheels on the first drive shaft is within the slip rate range, it is considered that the vehicle is in a transition working condition scene, and the differential protection strategy does not control the first motor to increase or decrease the torque.

[0170] For a four-wheel drive vehicle, the second drive shaft can also be controlled when the first drive shaft is controlled. For example, the method can also include:

[0171] In the case that the slip rate of the wheel with smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip rate range, and the slip rate of the wheel with smaller wheel speed among the two wheels on the second drive shaft of the vehicle is not higher than the upper limit of the slip rate range, the output torque of the second motor corresponding to the second drive shaft of the vehicle is controlled to be increased from a third torque to a fourth torque, and the first difference of the two wheels on the second drive shaft is not greater than a third safety threshold, which is a safety threshold corresponding to the case that the output torque of the second motor is the fourth torque.

[0172] For a four-wheel drive vehicle, when the slip rate of the wheel with smaller wheel speed of the other drive shaft does not exceed the upper limit, torque transfer can be performed to ensure the driving force of the vehicle as a whole.

[0173] Among them, the output torque control of the second motor can be stepwise or can be determined to be a safety output torque corresponding to the first difference of the two wheels on the second drive shaft, and then controlled. The detailed process can be referred to the control of the first motor.

[0174] In the case that the slip rate of the wheel with smaller wheel speed among the two wheels on the second drive shaft of the vehicle is higher than the upper limit of the slip rate range, the second motor corresponding to the second drive shaft is controlled to reduce the output torque, and the detailed process can be referred to the control of the first motor.

[0175] In addition, the embodiment provided in the application controls the wheel speed difference, and the traction control system intervenes earlier than the traction control system, avoids power problems caused by the intervention of the traction control system during the operation of the vehicle, and ensures the motion performance.

[0176] Figure 5 is a flowchart of a vehicle control method provided by the embodiment of the application. The method can be executed by a vehicle control unit or a motor controller of the vehicle. Taking the execution of the motor controller as an example, when the motor controller controls, the brake control unit cooperates to control, as shown in the figure, the method comprises the following steps: Figure 5

[0177] 301: Obtain the wheel speeds of the two wheels on the first drive shaft and the rotation speed of the first motor, and the output torque of the first motor corresponding to the first drive shaft is the first torque.

[0178] The motor controller obtains the wheel speeds of the two wheels on the first drive shaft output by the brake control unit of the vehicle through the vehicle control unit, and the motor controller obtains the rotation speed detected by the sensor in the first motor.

[0179] 302: Determine whether the wheel speeds of the two wheels on the first drive shaft are accurate according to the wheel speeds of the two wheels on the first drive shaft and the rotation speed of the first motor. In the case that the wheel speeds of the two wheels on the first drive shaft are accurate, step 304 is executed; otherwise, step 303 is executed.

[0180] For details of step 302, refer to step 202, which will not be repeated here.

[0181] 303: Output a fault prompt to prompt that the wheel speed sensor needs to be repaired or replaced.

[0182] Step 303 is an optional step.

[0183] 304: Determine the slip rate of the two wheels on the first drive shaft based on the wheel speeds of the two wheels on the first drive shaft and the rotation speed of the first motor.

[0184] For details of step 304, refer to step 204, which will not be repeated here.

[0185] 305: Obtain the first safety threshold corresponding to the case that the output torque of the first motor is the first torque from the correspondence between the motor output torque and the threshold.

[0186] For details of step 305, refer to step 205, which will not be repeated here.

[0187] 306: Determine whether the first difference of the two wheels on the first drive shaft of the vehicle is greater than the first safety threshold. In the case that the first difference of the two wheels on the first drive shaft is greater than the first safety threshold, step 307 is executed.​

[0188] Otherwise, the subsequent steps can not be performed, and the output torque of the first motor is maintained.

[0189] The detailed process of step 306 is described in step 206, which will not be repeated here.

[0190] 307: Determine whether the slip rate of the wheel with smaller wheel speed among the two wheels on the first drive shaft is higher than the lower limit of the slip rate range. If the slip rate of the wheel with smaller wheel speed among the two wheels on the first drive shaft is lower than the lower limit of the slip rate range, step 308 is performed. Otherwise, step 310 is performed.

[0191] The detailed process of step 307 is described in step 208, which will not be repeated here.

[0192] 308: Brake the wheel with larger wheel speed or slip rate among the two wheels on the first drive shaft.

[0193] The detailed process of step 308 is described in step 207, which will not be repeated here.

[0194] 309: Control the output torque of the first motor to increase from the first torque to the second torque, so that the first difference between the two wheels on the first drive shaft is not greater than the second safety threshold.

[0195] The detailed process of step 309 is described in step 209, which will not be repeated here.

[0196] 310: Determine whether the slip rate of the wheel with smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip rate range. If the slip rate of the wheel with smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip rate range, step 311 is performed. Otherwise, the output torque of the motor is maintained.

[0197] The detailed process of step 310 is described in step 210, which will not be repeated here.

[0198] 311: Control the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference between the two wheels on the first drive shaft is not greater than the second safety threshold.

[0199] The detailed process of step 311 is described in step 211, which will not be repeated here.

[0200] Figure 5 The method shown is different from the method provided in that the difference between the execution subjects is that braking is only performed in the escape scene, and no braking is performed in the high-speed cornering (drifting) scene. Figure 2 The method shown is different from the method provided in that the difference between the execution subjects is that braking is only performed in the escape scene, and no braking is performed in the high-speed cornering (drifting) scene.

[0201] Figure 6is a block diagram of a vehicle control device provided by an embodiment of the present application. The vehicle control device can be realized by software, hardware, or a combination of both as all or part of a vehicle control unit or a motor controller. The vehicle control device can include an acquisition unit 401 and a control unit 402.

[0202] The acquisition unit 401 is configured to acquire wheel speeds of two wheels on a first drive axle of a vehicle, the first drive axle being any drive axle of the vehicle, and the output torque of a first motor corresponding to the first drive axle being a first torque.

[0203] The control unit 402 is configured to, in a case where a first difference of the two wheels on the first drive axle is greater than a first safety threshold, control the output torque of the first motor to change from the first torque to a second torque based on a slip ratio of the two wheels on the first drive axle, so that the first difference of the two wheels on the first drive axle is not greater than a second safety threshold, the first difference being a wheel speed difference or a slip ratio difference, the first safety threshold being a safety threshold corresponding to a case where the output torque of the first motor is the first torque, and the second safety threshold being a safety threshold corresponding to a case where the output torque of the first motor is the second torque.

[0204] Optionally, the second torque is greater than the first torque.

[0205] The control unit 402 is configured to, in a case where the slip ratio of the wheel with the smaller wheel speed of the two wheels on the first drive axle is lower than a lower limit of a slip ratio range, brake the wheel with the larger wheel speed or slip ratio of the two wheels on the first drive axle, and control the output torque of the first motor to increase from the first torque to the second torque, so that the first difference of the two wheels on the first drive axle is not greater than the second safety threshold.

[0206] Optionally, the second torque is less than the first torque.

[0207] The control unit 402 is configured to, in a case where the slip ratio of the wheel with the smaller wheel speed of the two wheels on the first drive axle is higher than an upper limit of a slip ratio range, control the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive axle is not greater than the second safety threshold.

[0208] Optionally, the second torque is less than the first torque.

[0209] The control unit 402 is configured to, in a case where the slip ratio of the wheel with the smaller wheel speed of the two wheels on the first drive axle is higher than an upper limit of a slip ratio range, brake the wheel with the larger wheel speed or slip ratio of the two wheels on the first drive axle, and control the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive axle is not greater than the second safety threshold.

[0210] Optionally, the control unit 402 is configured to determine a second torque according to the first difference of the two wheels on the first drive shaft; output a control instruction based on the second torque; and control the output torque of the first motor by using the control instruction, so that the first difference of the two wheels on the first drive shaft is not greater than a second safety threshold.

[0211] Optionally, the control unit 402 is further configured to, in a case where the slip rate of the wheel with a smaller wheel speed among the two wheels on the first drive shaft is higher than the upper limit of the slip rate range and the slip rate of the wheel with a smaller wheel speed among the two wheels on the second drive shaft of the vehicle is not higher than the upper limit of the slip rate range, control the output torque of the second motor corresponding to the second drive shaft of the vehicle to be increased from a third torque to a fourth torque, and control the first difference of the two wheels on the second drive shaft to be not greater than a third safety threshold, the third safety threshold being a safety threshold corresponding to a case where the output torque of the second motor is the fourth torque.

[0212] Optionally, the acquisition unit 401 is further configured to acquire the rotation speed of the first motor.

[0213] The apparatus further includes a determination unit 403 configured to determine whether the wheel speeds are accurate according to the rotation speed of the first motor and the wheel speeds of the two wheels on the first drive shaft; and in a case where the wheel speeds of the two wheels on the first drive shaft are accurate, determine the slip rates of the two wheels on the first drive shaft based on the wheel speeds of the two wheels on the first drive shaft and the rotation speed of the first motor.

[0214] Optionally, the apparatus includes a vehicle control unit, or the apparatus includes a motor controller.

[0215] Optionally, the acquisition unit 401 is further configured to acquire a corresponding relationship between the motor output torque and the threshold value, the motor output torque and the threshold value being negatively correlated; and acquire the first safety threshold corresponding to a case where the output torque of the first motor is the first torque from the corresponding relationship between the motor output torque and the threshold value.

[0216] The vehicle control apparatus provided by the above-described embodiments is in operation, and only the division of the above-described functional units is exemplified, and in actual application, the above-described functions can be completed by different functional units according to needs, that is, the internal structure of the device is divided into different functional units to complete all or part of the above-described functions. In addition, the vehicle control apparatus and the vehicle control method provided by the above-described embodiments belong to the same concept, and the specific implementation process is described in the method embodiments, which will not be described here.

[0217] The description of the flow corresponding to each of the above-described figures has its own emphasis, and the parts not described in detail in a certain flow can be referred to the related description of other flows.

[0218] The embodiments of the present application also provide a vehicle. Figure 6The vehicle control device and the motor are connected.

[0219] Figure 7 A structure diagram of a vehicle control device 900 is shown. Figure 7 The vehicle control device 900 is configured to perform operations involved in the vehicle control method shown in Figure 2 , Figure 3 or Figure 5 . The vehicle control device 900 can include the vehicle control unit or the motor controller. The vehicle control device 900 can be implemented by a general bus architecture.

[0220] As shown in Figure 7 , the vehicle control device 900 includes at least one processor 901, a memory 903 and at least one communication interface 904.

[0221] The processor 901 is, for example, a general central processing unit (CPU), a digital signal processor (DSP), a network processer (NP), a graphics processing unit (GPU), a neural-network processing units (NPU), a data processing unit (DPU), a microprocessor or one or more integrated circuits for implementing the schemes of the present application. For example, the processor 901 includes an application-specific integrated circuit (ASIC), a programmable logic device (PLD) or other programmable logic device, transistor logic, a hardware component or any combination thereof. The PLD is, for example, a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL) or any combination thereof. It can implement or execute various logical blocks, modules and circuits described in combination with the disclosure of the embodiments of the present application. The processor can also be a combination of computing functions, such as one or more microprocessor combinations, combinations of DSP and microprocessor, etc.

[0222] Optionally, the vehicle control device 900 further includes a bus. The bus is used to transmit information between the components of the vehicle control device 900. The bus can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 7 Only one bus is represented by a thick line, but this does not indicate that there is only one bus or only one type of bus.

[0223] The memory 903 is, for example, a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a random access memory (RAM) or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, a magnetic disk storage or other magnetic storage devices, or any other medium capable of storing desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited to this. The memory 903 is, for example, independent and connected to the processor 901 through the bus. The memory 903 can also be integrated with the processor 901.

[0224] The communication interface 904 uses any transceiver-like device for communicating with other devices or communication networks, which can be an Ethernet network, a radio access network (RAN), a Bluetooth network, etc. The communication interface 904 can include a wired communication interface and can also include a wireless communication interface. In the embodiments of the present application, the communication interface 904 can be used for the vehicle control device 900 to communicate with other devices.

[0225] In a specific implementation, as an embodiment, the processor 901 can include one or more CPUs, such as Figure 7CPU0 and CPU1 shown in FIG. 1. Each of these processors can be a single-CPU processor or a multi-CPU processor. A processor herein can refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions).

[0226] In a specific implementation, as an example, the vehicle control device 900 can include multiple processors, such as the processor 901 and the processor 905 shown in FIG. 1. Each of these processors can be a single-CPU processor or a multi-CPU processor. A processor herein can refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions). Figure 7

[0227] In a specific implementation, as an example, the vehicle control device 900 can further include an output device and an input device. The output device is in communication with the processor 901 and can display information in various ways. For example, the output device can be a liquid crystal display (LCD), a light emitting diode (LED) display device, a cathode ray tube (CRT) display device, a projector, or the like. The input device is in communication with the processor 901 and can receive user input in various ways. For example, the input device can be a touch screen device, a sensor device, or the like.

[0228] In some embodiments, the memory 903 is configured to store program code 910 for implementing the solutions of the present application, and the processor 901 can execute the program code 910 stored in the memory 903. That is, the vehicle control device 900 can implement the vehicle control method provided by the method embodiments through the processor 901 and the program code 910 in the memory 903. The program code 910 can include one or more software modules. Alternatively, the processor 901 itself can also store program codes or instructions for implementing the solutions of the present application.

[0229] In a specific implementation, the vehicle control device 900 of the embodiments of the present application can correspond to the motor control module or the motor controller in the above-mentioned various method embodiments. The processor 901 in the vehicle control device 900 reads the instructions in the memory 903, so that the vehicle control device 900 can perform all or part of the operations performed by the motor control module or the motor controller. Figure 7 The vehicle control device 900 shown in FIG. 1 can perform all or part of the operations performed by the motor control module or the motor controller.

[0230] ​Specifically, the processor 901 is used to obtain the wheel speeds of the two wheels on the first drive axle of the vehicle. The first drive axle is any drive axle of the vehicle, and the output torque of the first motor corresponding to the first drive axle is a first torque. If the first difference between the two wheels on the first drive axle is greater than a first safety threshold, based on the slip ratio of the two wheels on the first drive axle, the processor controls the output torque of the first motor to change from the first torque to a second torque so that the first difference between the two wheels on the first drive axle is not greater than a second safety threshold. The first difference is the wheel speed difference or slip ratio difference. The first safety threshold is the safety threshold corresponding to the first motor output torque being the first torque, and the second safety threshold is the safety threshold corresponding to the first motor output torque being the second torque.

[0231] Other alternative implementation methods will not be described in detail here for the sake of brevity.

[0232] The vehicle control device 900 can also correspond to the above. Figure 6 The vehicle control device shown in the diagram is implemented using software from the vehicle control equipment 900. In other words, the functional modules of the vehicle control device are generated by the processor 901 of the vehicle control equipment 900 reading the program code 910 stored in the memory 903.

[0233] in, Figure 2 , Figure 3 or Figure 5 Each step of the vehicle control method shown is completed through integrated logic circuits in the hardware or instructions in the software form of the processor of the vehicle control device 900. The steps of the method disclosed in the embodiments of this application can be directly implemented by the hardware processor, or by a combination of hardware and software modules in the processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. Since this storage medium is located in memory, the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method; to avoid repetition, these will not be described in detail here.

[0234] This application also provides a chip, including: an input interface, an output interface, a processor, and a memory. The input interface, output interface, processor, and memory are connected through an internal connection path. The processor is used to execute code in the memory. When the code is executed, the processor is used to execute any of the above-described vehicle control methods.

[0235] It is to be understood that the above-described processor can be a CPU, and can also be other general-purpose processors, DSPs, ASICs, FPGAs or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc. It is to be noted that the processor can be an ARM architecture processor.

[0236] Further, in an alternative embodiment, the above-described processor is one or more, and the memory is one or more. Optionally, the memory can be integrated with the processor, or the memory can be disposed separately from the processor. The above-described memory can include read-only memory and random access memory, and provide instructions and data to the processor. The memory can also include non-volatile random access memory. For example, the memory can also store reference blocks and target blocks.

[0237] The memory can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be ROM, PROM, EPROM, EEPROM or flash memory. The volatile memory can be RAM, which is used as an external cache. By way of example but not limitation, many forms of RAM can be used. For example, SRAM, DRAM, SDRAM, DDR SDRAM, ESDRAM, SLDRAM and DR RAM.

[0238] In the embodiments of the present application, a computer readable storage medium is also provided, and the computer readable storage medium stores computer instructions. When the computer instructions stored in the computer readable storage medium are executed by the vehicle control device, the vehicle control device executes the above-provided vehicle control method.

[0239] In the embodiments of the present application, a computer program product containing instructions is also provided, and when the computer program product is run on the vehicle control device, the vehicle control device executes the above-provided vehicle control method.

[0240] In the above embodiments, all or part of the steps can be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the steps can be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the present application are generated. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be transferred from one website, computer, server or data center to another website, computer, server or data center through wired (such as coaxial cable, optical fiber, digital subscriber line) or wireless (such as infrared, wireless, microwave, etc.) manner. The computer readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. integrated with one or more available media. The available media can be magnetic media (such as floppy disk, hard disk, magnetic tape), optical media (such as DVD), or semiconductor media (such as solid state disk), etc.

[0241] Those of ordinary skill in the art understand that all or part of the steps of the above embodiments can be completed by hardware, or by program to instruct related hardware, and the program can be stored in a computer readable storage medium, and the storage medium mentioned above can be read only memory, magnetic disk or optical disk, etc.

[0242] The above is only an optional embodiment of the present application, but the protection scope of the present application is not limited thereto. Any changes or replacements within the technical scope disclosed in the present application can be easily thought by those skilled in the art, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A vehicle control method characterized by, The method comprises: obtaining wheel speeds of two wheels on a first drive axle of a vehicle, the first drive axle being any drive axle of the vehicle, and the first drive axle corresponding to a first motor whose output torque is a first torque; in a case where a first difference of the two wheels on the first drive axle is greater than a first safety threshold, and a slip ratio of a wheel with a smaller wheel speed among the two wheels on the first drive axle is lower than a lower limit of a slip ratio range, braking a wheel with a larger wheel speed or slip ratio among the two wheels on the first drive axle; and controlling the output torque of the first motor to increase from the first torque to a second torque, so that the first difference of the two wheels on the first drive axle is not greater than a second safety threshold, the second torque being greater than the first torque, the first difference being a wheel speed difference or a slip ratio difference, the first safety threshold being a safety threshold corresponding to the first motor whose output torque is the first torque, and the second safety threshold being a safety threshold corresponding to the first motor whose output torque is the second torque; in a case where the slip ratio of the wheel with the smaller wheel speed among the two wheels on the first drive axle is higher than an upper limit of the slip ratio range, and the slip ratio of a wheel with a smaller wheel speed among two wheels on a second drive axle of the vehicle is not higher than the upper limit of the slip ratio range, controlling the output torque of a second motor corresponding to the second drive axle to increase from a third torque to a fourth torque, and making a first difference of the two wheels on the second drive axle not greater than a third safety threshold, the third safety threshold being a safety threshold corresponding to the second motor whose output torque is the fourth torque.

2. The method of claim 1, wherein, The method further comprises: in a case where the first difference of the two wheels on the first drive axle is greater than the first safety threshold, and the slip ratio of the wheel with the smaller wheel speed among the two wheels on the first drive axle is higher than the upper limit of the slip ratio range, controlling the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive axle is not greater than the second safety threshold, the second torque being smaller than the first torque.

3. The method of claim 1, wherein, The method further comprises: in a case where the first difference of the two wheels on the first drive axle is greater than the first safety threshold, and the slip ratio of the wheel with the smaller wheel speed among the two wheels on the first drive axle is higher than the upper limit of the slip ratio range, braking the wheel with the larger wheel speed or slip ratio among the two wheels on the first drive axle; controlling the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive axle is not greater than the second safety threshold, the second torque being smaller than the first torque.

4. The method according to any one of claims 1 to 3, characterized in that, controlling the output torque of the first motor to change from the first torque to the second torque, so that the first difference of the two wheels on the first drive axle is not greater than the second safety threshold, comprises: The second torque is determined according to a first difference of the two wheels on the first drive shaft; a control instruction is output based on the second torque; and the output torque of the first motor is controlled by using the control instruction, so that the first difference of the two wheels on the first drive shaft is not greater than a second safety threshold.

5. The method according to any one of claims 1 to 3, characterized in that, The method further comprises: obtaining the rotating speed of the first motor; determining whether the wheel speed is accurate according to the rotating speed of the first motor and the wheel speed of the two wheels on the first drive shaft; and in the case that the wheel speed of the two wheels on the first drive shaft is accurate, determining the slip rate of the two wheels on the first drive shaft based on the wheel speed of the two wheels on the first drive shaft and the rotating speed of the first motor.

6. The method according to any one of claims 1 to 3, characterized in that, The method is executed by a vehicle control unit or a motor controller.

7. The method according to any one of claims 1 to 3, characterized in that, The method further comprises: obtaining a corresponding relationship between the motor output torque and the threshold value, wherein the motor output torque and the threshold value are negatively correlated; obtaining the first safety threshold value corresponding to the output torque of the first motor before dynamic control from the corresponding relationship between the motor output torque and the threshold value.

8. A vehicle control device characterized by comprising: The device comprises: an obtaining unit configured to obtain the wheel speed of the two wheels on a first drive shaft of a vehicle, wherein the first drive shaft is any drive shaft of the vehicle, and the output torque of a first motor corresponding to the first drive shaft is a first torque; a control unit configured to brake a wheel with a larger wheel speed or slip rate among the two wheels on the first drive shaft in the case that the first difference of the two wheels on the first drive shaft is greater than a first safety threshold value, and the slip rate of a wheel with a smaller wheel speed among the two wheels on the first drive shaft is lower than a lower limit of a slip rate range; and increase the output torque of the first motor from the first torque to a second torque, so that the first difference of the two wheels on the first drive shaft is not greater than a second safety threshold value, wherein the second torque is greater than the first torque, the first difference is a wheel speed difference or a slip rate difference, the first safety threshold value is a safety threshold value corresponding to the first torque of the first motor, and the second safety threshold value is a safety threshold value corresponding to the second torque of the first motor. The control unit is further configured to increase the output torque of a second motor corresponding to a second drive shaft of the vehicle from a third torque to a fourth torque, and make the first difference of the two wheels on the second drive shaft not greater than a third safety threshold value in the case that the slip rate of a wheel with a smaller wheel speed among the two wheels on the second drive shaft is higher than an upper limit of a slip rate range, and the slip rate of a wheel with a smaller wheel speed among the two wheels on the second drive shaft is not higher than the upper limit of the slip rate range, wherein the third safety threshold value is a safety threshold value corresponding to the fourth torque of the second motor.

9. The apparatus of claim 8, wherein, The second torque is less than the first torque. The control unit is further configured to, in a case where the first difference of the two wheels on the first drive shaft is greater than the first safety threshold and the slip ratio of the wheel with the smaller wheel speed of the two wheels on the first drive shaft is higher than the upper limit of the slip ratio range, control the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

10. The apparatus of claim 8, wherein, The second torque is less than the first torque. The control unit is further configured to, in a case where the first difference of the two wheels on the first drive shaft is greater than the first safety threshold and the slip ratio of the wheel with the smaller wheel speed of the two wheels on the first drive shaft is higher than the upper limit of the slip ratio range, brake the wheel with the larger wheel speed or slip ratio of the two wheels on the first drive shaft; control the output torque of the first motor to decrease from the first torque to the second torque, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

11. The apparatus of any one of claims 8 to 10, wherein, The control unit is configured to determine the second torque according to the first difference of the two wheels on the first drive shaft; output a control instruction based on the second torque; and control the output torque of the first motor by using the control instruction, so that the first difference of the two wheels on the first drive shaft is not greater than the second safety threshold.

12. The apparatus of any one of claims 8 to 10, wherein, The acquisition unit is further configured to acquire the rotation speed of the first motor. The device further includes: A determination unit configured to determine whether the wheel speeds are accurate according to the rotation speed of the first motor and the wheel speeds of the two wheels on the first drive shaft; and in a case where the wheel speeds of the two wheels on the first drive shaft are accurate, determine the slip ratios of the two wheels on the first drive shaft based on the wheel speeds of the two wheels on the first drive shaft and the rotation speed of the first motor.

13. The apparatus of any one of claims 8 to 10, wherein, The device includes a vehicle control unit, or the device includes a motor controller.

14. The apparatus of any one of claims 8 to 10, wherein, The acquisition unit is further configured to acquire a corresponding relationship between a motor output torque and a threshold value, the motor output torque and the threshold value being negatively correlated; and acquire the first safety threshold corresponding to the output torque of the first motor before dynamic control from the corresponding relationship between the motor output torque and the threshold value.

15. A vehicle characterized by comprising: The vehicle includes the vehicle control device according to any one of claims 8 to 14 and a motor, and the vehicle control device is connected to the motor.

16. A vehicle control apparatus characterized by comprising: The vehicle control device includes a processor and a memory, the memory is configured to store a software program, and the processor is configured to execute or run the software program stored in the memory, so that the vehicle control device implements the method according to any one of claims 1 to 7.

17. A computer-readable storage medium, characterized in that, The computer readable storage medium is configured to store program code executed by a processor, and the program code includes instructions for implementing the method according to any one of claims 1 to 7.

18. A computer program product, characterised in that, The computer program product includes computer program code, when the computer program code is run by a computer, the computer program code causes the computer to execute instructions of the method according to any one of claims 1 to 7.

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