Torque control method, device, system, chip and vehicle

Abstract

Provided are a torque control method, device, system, chip and vehicle, which relate to the field of vehicle control technology, can improve the steering performance of the vehicle, improve the controllability of the vehicle driving, and also improve the safety of vehicle driving. In this method, the yaw acceleration, lateral acceleration, original distribution torque of the front axle and original distribution torque of the rear axle of the vehicle are first obtained. Then, according to the yaw acceleration and the lateral acceleration, the required torque of the whole vehicle after compensation, the first torque after compensation of the original distribution torque of the front axle and the second torque after compensation of the original distribution of the rear axle are determined. Then, according to the lateral acceleration and the required torque of the whole vehicle after compensation, the transfer torque is determined, wherein the transfer torque represents the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle. Finally, the first torque and the second torque are intervened respectively by using the transfer torque.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a torque control method, device, system, chip and vehicle. Background Art

[0002] At present, for four-wheel drive electric vehicles, a front and rear dual-motor four-wheel drive structure can be adopted. In this structure, a motor arranged on the front axle drives the two wheels on the front axle, and a motor arranged on the rear axle drives the two wheels on the rear axle. The front axle motor and the rear axle motor output torque independently, thereby realizing torque control of the front and rear axles, and through torque control to reasonably distribute the driving force or braking force between the front and rear axles, fully utilize the vehicle's adhesion limit, and improve vehicle stability and safety.

[0003] In some torque control technical solutions, torque control can be performed based on the lateral acceleration of the vehicle or the steering wheel angle. For example, when turning, as the lateral acceleration increases, the braking force of the entire vehicle is increased based on torque control, and the braking force is increased to the rear axle based on the torque compensation of the front and rear axles. As the lateral acceleration decreases, the driving force of the entire vehicle is increased based on torque control, and the driving force is increased to the front axle based on the torque compensation of the front and rear axles. When performing torque compensation, the torque that needs to be adjusted for the entire vehicle can be determined first, and then the torque that needs to be adjusted can be distributed to the front and rear axles in a certain proportion. The increase in driving force or braking force is determined based on the distributed torque.

[0004] However, although the above method can realize torque control of the vehicle, when the vehicle is performing such torque control, less torque is allocated to the front and rear axles during the torque compensation process, resulting in a smaller torque adjustment range of the front and rear axles. This makes it impossible to fully utilize the tires, limits vehicle stability and handling, and even affects vehicle driving safety. Summary of the invention

[0005] The embodiments of the present application provide a torque control method, device, system, chip and vehicle, which can improve the steering performance of the vehicle, improve the controllability and stability of the vehicle driving, and also improve the safety of vehicle driving.

[0006] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0007] In a first aspect, a torque control method is provided, in which the yaw acceleration, lateral acceleration, original distribution torque of the front axle and original distribution torque of the rear axle of the vehicle are first obtained. Then, the required torque of the whole vehicle after compensation, the first torque after compensation of the original distribution torque of the front axle and the second torque after compensation of the original distribution of the rear axle are determined according to the yaw acceleration and the lateral acceleration. Then, the transfer torque is determined according to the lateral acceleration and the required torque of the whole vehicle after compensation, wherein the transfer torque represents the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle. Finally, the first required torque of the front axle of the vehicle is determined according to the transfer torque and the first torque, and the second required torque of the rear axle of the vehicle is determined according to the transfer torque and the second torque, wherein the transfer torque is used to intervene in the first torque and the second torque respectively.

[0008] In the above method, the original distributed torque of the front axle and the original distributed torque of the rear axle of the vehicle can be compensated respectively, and on this basis, the torque transfer is performed using the compensated vehicle demand torque of the vehicle, that is, the first torque and the second torque after the front and rear axles are further intervened by the transferred torque, so as to realize the torque control of the vehicle. In this method, on the basis of compensating the original distributed torque of the front and rear axles, the torque after the front axle is further transferred after compensation, which can increase the torque adjustment range of the front and rear axles during the torque control process, so that the adjusted front and rear axle torques can meet the turning requirements of the vehicle as much as possible, and improve the steering performance or ability of the vehicle. Moreover, after the torque adjustment range is increased, it can also ensure that the actual torque of the front and rear axles after the transferred torque intervention is closer to the expected torque that meets the turning requirements of the vehicle, improve the controllability and stability of the vehicle driving, and also improve the safety of the vehicle driving.

[0009] In an implementable method of the first aspect, when determining the transfer torque based on the lateral acceleration and the compensated vehicle required torque, the lateral jerk of the vehicle can be determined based on the lateral acceleration; the torque transfer rate can be determined based on the lateral jerk; and the transfer torque can be determined based on the torque transfer rate and the compensated vehicle required torque.

[0010] In this implementation, the transfer torque represents the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle, and the transfer torque is determined according to the required torque of the whole vehicle after compensation. The range of the required torque of the whole vehicle after compensation is larger, so the range of the torque that can be transferred by the front and rear axles is also larger, so that the torque transfer can increase the torque adjustment range of the front and rear axles, so that the torque of the front and rear axles after the transfer torque or adjustment can meet the turning requirements of the vehicle, and improve the steering performance or ability of the vehicle. Moreover, after the torque adjustment range is increased, it can also ensure that the actual torque of the front and rear axles after the transfer torque intervention is closer to the expected torque that meets the turning requirements of the vehicle, improve the controllability of the vehicle driving, and also improve the safety of the vehicle driving.

[0011] In an implementation method of the first aspect, when determining a first torque after compensating the original distributed torque of the front axle and a second torque after compensating the original distributed torque of the rear axle, the compensation torque distribution rate can be determined according to the yaw angular acceleration; the front axle compensation torque and the rear axle compensation torque of the vehicle can be determined respectively according to the compensation torque distribution rate and the whole vehicle compensation torque; the first torque of the front axle is determined according to the front axle compensation torque and the original distributed torque of the front axle, and the second torque of the rear axle is determined according to the rear axle compensation torque and the original distributed torque of the rear axle, wherein the front axle compensation torque is used to compensate for the original distributed torque of the front axle, and the rear axle compensation torque is used to compensate for the original distributed torque of the rear axle.

[0012] In this implementation, the yaw angular acceleration of the vehicle when turning can characterize the working state of the vehicle when turning to a certain extent. Therefore, the compensation torque of the front and rear axles of the vehicle is determined according to the yaw angular acceleration, and the original distributed torque of the front and rear axles is compensated. When the understeer tendency of the vehicle increases, the torque of the front axle can be reduced, the grip of the front axle tire can be improved, and the understeer situation can be improved; when the oversteer tendency of the vehicle increases, the torque of the rear axle can be reduced, the grip of the rear axle tire can be improved, and the oversteer situation can be improved.

[0013] In an implementable manner of the first aspect, when determining the compensated vehicle required torque based on the yaw angular acceleration and the lateral acceleration, the vehicle's whole vehicle compensation torque can be determined based on the yaw angular acceleration and the lateral acceleration; the vehicle's compensated vehicle required torque can be determined based on the vehicle compensation torque and the requested torque; and the vehicle compensation torque is used to compensate for the requested torque.

[0014] In this implementation, the yaw acceleration and lateral acceleration of the vehicle when turning can characterize the working state of the vehicle when turning. Therefore, the compensation torque of the vehicle is determined based on the yaw acceleration and the lateral acceleration, and the requested torque of the vehicle is compensated by using the compensation torque, for example, the requested torque is reduced or increased, etc., thereby improving the adhesion and grip of the front or rear wheels, thereby reducing understeer or oversteer of the vehicle when turning to a certain extent.

[0015] In an implementation method of the first aspect, when a first required torque of a front axle of the vehicle is determined based on the transfer torque and the first torque, and a second required torque of a rear axle of the vehicle is determined based on the transfer torque and the second torque, the current operating state of the vehicle can be obtained; the operating state is related to the yaw angular acceleration and the lateral jerk, wherein the lateral jerk is used to characterize the rate of change of the lateral acceleration; according to the operating state, a torque control strategy is determined; based on the torque control strategy, the first required torque of the front axle of the vehicle is determined based on the transfer torque and the first torque, and the second required torque of the rear axle of the vehicle is determined based on the transfer torque and the second torque.

[0016] In an implementation method of the first aspect, the working state includes a steady state and an unstable state; when the values ​​of the yaw angular acceleration and the lateral jerk include positive values ​​or negative values, the working state is a steady state; when the values ​​of the yaw angular acceleration and the lateral jerk include positive values ​​and negative values, the working state is an unstable state.

[0017] In this implementation method, the vehicle's working state can be more finely divided into steady state (such as steering, returning to the center state), unstable state (such as pushing the head, drifting the tail) and other working states. Different torque control strategies can be adopted for different working states, thereby covering a variety of steady and unstable state situations, so that the vehicle can perform torque control well in different working states, reduce the impact of understeer or oversteer, and ensure the vehicle's controllability and stability.

[0018] In an implementation method of the first aspect, when determining the torque control strategy according to the working state, when the working state is steady state, if the value of the yaw angular acceleration and the value of the lateral jerk are both positive values, then the torque control strategy is determined to transfer the torque from the front axle to the rear axle, and, if the type of the requested torque is driving torque, then the compensation method for the requested torque is torque reduction, and if the type of the requested torque is recovery torque, then the compensation method for the requested torque is torque increase, wherein the type of the requested torque is determined according to the state of the accelerator pedal or the brake pedal of the vehicle.

[0019] If the value of the yaw angular acceleration and the value of the lateral jerk are both negative values, the torque control strategy is determined to transfer the torque from the rear axle to the front axle, and if the type of the requested torque is driving torque, the compensation method for the requested torque is torque increase, and if the type of the requested torque is recovery torque, the compensation method for the requested torque is torque reduction.

[0020] In this implementation, if the value of the yaw angular acceleration and the value of the lateral jerk are both positive, the vehicle is in a steering state. In order to maintain the current stable state of the vehicle, the driving torque requested by the vehicle is reduced, and the torque compensated to the front and rear axles will reduce the driving torque of the front and rear axles, so that the vehicle load (or vertical load) moves forward, and the front axle tire adhesion and grip are improved; and the transfer torque is transferred from the front axle to the rear axle, which can also reduce the front axle torque, change the tire utilization rate, reduce the front wheel slip, and reduce the occurrence of understeering. Alternatively, when the vehicle itself is in a stable steering state, in order to maintain the current steering state of the vehicle, the recovery torque requested by the vehicle is increased, which can also be equivalent to reducing the driving torque. At the same time, the torque compensated to the front and rear axles will increase the recovery torque of the front and rear axles, and can also improve the front axle tire adhesion and grip; and the transfer torque is transferred from the front axle to the rear axle, which can also reduce the front axle torque, change the tire utilization rate, reduce the front wheel slip, and reduce the occurrence of understeering.

[0021] If the values ​​of the yaw angular acceleration and the lateral jerk are both negative, the vehicle is in a return-to-center state. In order to maintain the current stable state of the vehicle, the requested drive torque of the vehicle is increased, and the torque compensated to the front and rear axles will increase the drive torque of the front and rear axles, so that the vehicle load (or vertical load) moves backward, and the adhesion and grip of the rear axle tire are improved; and the transfer torque is transferred from the rear axle to the front axle, which can also reduce the rear axle torque, change the tire utilization rate, reduce the rear wheel slip, and reduce the occurrence of oversteering. Alternatively, when the vehicle itself is in a stable return-to-center state, in order to maintain the current stable state of the vehicle, the requested recovery torque of the vehicle is reduced, which can also be equivalent to increasing the drive torque. At the same time, the torque compensated to the front and rear axles will reduce the recovery torque of the front and rear axles, so that the vehicle load moves backward, improve the adhesion and grip of the rear axle tire, and also improve the acceleration and stability of the vehicle when returning to the center; and the transfer torque is transferred from the rear axle to the front axle, which can also reduce the rear axle torque, change the tire utilization rate, reduce the rear wheel slip, and reduce the occurrence of oversteering.

[0022] In an implementation method of the first aspect, when determining the torque control strategy according to the working state, when the working state is an unstable state, if the value of the yaw angular acceleration is a negative value and the value of the lateral jerk is a positive value, then the torque control strategy is determined to transfer the torque from the front axle to the rear axle, and the compensation method for the requested torque is torque reduction.

[0023] If the value of the yaw acceleration is positive and the value of the lateral jerk is negative, the torque control strategy is determined to transfer the torque from the rear axle to the front axle, and the compensation method for the requested torque is torque reduction.

[0024] In this implementation, if the value of the yaw angular acceleration is negative and the value of the lateral jerk is positive, the vehicle is in a push-head state. At this time, the drive torque requested by the vehicle is reduced, and the torque compensated to the front and rear axles will reduce the drive torque of the front and rear axles, so that the vehicle load moves forward, and the front axle tire adhesion and grip are improved; and the transfer torque is transferred from the front axle to the rear axle, which can also reduce the front axle torque, change the tire utilization rate, reduce the front wheel slip, and reduce the occurrence of push-head situations. Alternatively, when the vehicle is in an unstable state, the recovery torque requested by the vehicle is reduced, which is equivalent to increasing the drive torque, and the torque compensated to the front and rear axles will reduce the recovery torque of the front and rear axles, while the drive torque is increased, so that the vehicle load moves forward, and the front axle tire adhesion and grip are improved; and the transfer torque is transferred from the front axle to the rear axle, which can also reduce the front axle torque, reduce the front wheel slip, and reduce the occurrence of push-head situations.

[0025] If the value of the yaw angular acceleration is positive and the value of the lateral jerk is negative, the vehicle is in a tail-swinging state. At this time, the driving torque requested by the vehicle is reduced, and the torque compensated to the front and rear axles will reduce the driving torque of the front and rear axles, so that the vehicle load moves backward, and the rear axle tire adhesion and grip are improved; and the transfer torque is transferred from the rear axle to the front axle, which can also reduce the rear axle torque, change the tire utilization rate, reduce the rear wheel slip, and reduce the occurrence of tail-swinging. Alternatively, when the vehicle is in an unstable state, the recovery torque requested by the vehicle is reduced, which is equivalent to the driving torque increase, and the torque compensated to the front and rear axles will reduce the recovery torque of the front and rear axles, while the driving torque is increased, so that the vehicle load moves backward, and the rear axle tire adhesion and grip are improved; and the transfer torque is transferred from the rear axle to the front axle, which can also reduce the rear axle torque, change the tire utilization rate, reduce the rear wheel slip, and reduce the occurrence of tail-swinging.

[0026] In an implementation of the first aspect, based on a torque control strategy, determining a first required torque of a front axle of a vehicle according to a transfer torque and a first torque, and determining a second required torque of a rear axle of the vehicle according to the transfer torque and the second torque include:

[0027] When the torque control strategy is to distribute the transfer torque from the front axle to the rear axle, the transfer torque is reduced on the first torque to obtain the first required torque, and the transfer torque is superimposed on the second torque to obtain the second required torque; or

[0028] When the torque control strategy is to distribute the transfer torque from the rear axle to the front axle, the transfer torque is superimposed on the first torque to obtain the first required torque, and the transfer torque is reduced on the second torque to obtain the second required torque.

[0029] In an implementation of the first aspect, the method further includes: obtaining the front axle load and the rear axle load of the vehicle; determining the front axle torque limit range of the vehicle according to the lateral acceleration and the front axle load, and determining the rear axle torque limit range of the vehicle according to the lateral acceleration and the rear axle load, wherein the front axle torque limit range is used to limit the amplitude of the first required torque, and the rear axle torque limit range is used to limit the amplitude of the second required torque. And, the method further includes: controlling the front axle motor to output the final first required torque after the amplitude of the first required torque is limited, and controlling the rear axle motor to output the final second required torque after the amplitude of the second required torque is limited.

[0030] This method of limiting the amplitude of the first required torque and the second required torque can ensure the steering performance of the vehicle as much as possible while reducing the excessive variation in the amplitude of the torque output by the front and rear axle motors, thereby ensuring the stability of the vehicle's driving.

[0031] In one implementation of the first aspect, when obtaining the original distributed torque of the front axle and the original distributed torque of the rear axle, the current pedal travel information and the current vehicle speed information of the vehicle can be obtained, wherein the pedal travel information is used to indicate the distance moved when the brake pedal is pressed or the distance moved when the accelerator pedal is pressed; based on the pedal travel information, the requested torque of the vehicle is determined; the original torque distribution rate corresponding to the requested torque and the vehicle speed information is obtained; and the original distributed torque of the front axle and the original distributed torque of the rear axle are determined based on the requested torque and the original torque distribution rate.

[0032] In a second aspect, a torque control device is provided, including: an information acquisition unit for acquiring the vehicle's yaw acceleration, lateral acceleration, original distributed torque of the front axle and original distributed torque of the rear axle; a torque compensation unit for determining the compensated vehicle demand torque, the first torque after compensating the original distributed torque of the front axle and the second torque after compensating the original distributed torque of the rear axle according to the yaw acceleration and the lateral acceleration; a torque transfer unit for determining the transfer torque according to the lateral acceleration and the compensated vehicle demand torque; the transfer torque represents the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle; a processing unit for determining the first required torque of the front axle of the vehicle according to the transfer torque and the first torque, and determining the second required torque of the rear axle of the vehicle according to the transfer torque and the second torque; the transfer torque is used to intervene in the first torque and the second torque respectively.

[0033] In an implementation method of the second aspect, the torque transfer unit is also used to determine the lateral jerk of the vehicle based on the lateral acceleration; determine the torque transfer rate based on the lateral jerk; and determine the transfer torque based on the torque transfer rate and the compensated vehicle required torque.

[0034] In an implementation method of the second aspect, the torque compensation unit is also used to determine the compensation torque distribution rate according to the yaw angular acceleration; determine the front axle compensation torque and the rear axle compensation torque of the vehicle respectively according to the compensation torque distribution rate and the whole vehicle compensation torque; determine the first torque of the front axle according to the front axle compensation torque and the original distributed torque of the front axle, and determine the second torque to compensate the rear axle according to the rear axle compensation torque and the original distributed torque of the rear axle; the front axle compensation torque is used to compensate the original distributed torque of the front axle, and the rear axle compensation torque is used to compensate the original distributed torque of the rear axle.

[0035] In an implementation method of the second aspect, the torque compensation unit is also used to determine the vehicle's whole vehicle compensation torque based on the yaw angular acceleration and the lateral acceleration; determine the vehicle's compensated whole vehicle required torque based on the vehicle's whole vehicle compensation torque and the requested torque; and the vehicle's whole vehicle compensation torque is used to compensate for the requested torque.

[0036] In an implementation method of the second aspect, the processing unit is also used to obtain the current operating state of the vehicle; the operating state is related to the yaw angular acceleration and the lateral jerk; the lateral jerk is used to characterize the rate of change of the lateral acceleration; according to the operating state, the torque control strategy is determined; based on the torque control strategy, the first required torque of the front axle of the vehicle is determined according to the transfer torque and the first torque, and the second required torque of the rear axle of the vehicle is determined according to the transfer torque and the second torque.

[0037] In an implementation manner of the second aspect, the information acquisition unit includes an inertial sensor; the inertial sensor is used to acquire the yaw angular acceleration and lateral acceleration of the vehicle.

[0038] In a third aspect, a torque control system is provided, comprising a processor, and an inertial sensor, a steering wheel, an accelerator pedal, a brake pedal, a front axle motor, and a rear axle motor respectively connected to the processor; the inertial sensor is used to obtain the yaw angular acceleration and lateral acceleration of the vehicle, and send the yaw angular acceleration and lateral acceleration to the processor;

[0039] A processor, used to obtain steering wheel angle information, accelerator pedal travel information, and brake pedal travel information;

[0040] The processor is also used to determine the original distributed torque of the front axle and the original distributed torque of the rear axle of the vehicle in response to the steering angle information and according to the pedal travel information of the accelerator pedal or the pedal travel information of the brake pedal; and, according to the yaw angular acceleration and the lateral acceleration, determine the compensated vehicle demand torque, the first torque after compensating the original distributed torque of the front axle and the second torque after compensating the original distributed torque of the rear axle; determine the transfer torque according to the lateral acceleration and the compensated vehicle demand torque; the transfer torque represents the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle; determine the first required torque of the front axle of the vehicle according to the transfer torque and the first torque, and determine the second required torque of the rear axle of the vehicle according to the transfer torque and the second torque; the transfer torque is used to intervene in the first torque and the second torque respectively.

[0041] In a fourth aspect, a chip is provided, comprising a memory and one or more processors; the memory is coupled to the processor; wherein computer program code is stored in the memory, and the computer program code comprises computer instructions, and when the computer instructions are executed by the processor, the chip executes the torque control method as in the first aspect and any implementation thereof.

[0042] In a fifth aspect, a vehicle is provided, comprising a torque control device as in the first aspect and any implementation thereof, or comprising a chip as described in the fourth aspect.

[0043] In a sixth aspect, a computer-readable storage medium is provided, comprising computer instructions. When the computer instructions are executed on a chip, the chip executes the torque control method as in the first aspect and any implementation thereof.

[0044] In a seventh aspect, a computer program product is provided. When the computer program product is run on a computer, the computer executes the torque control method as in the first aspect and any implementation thereof.

[0045] It can be understood that the beneficial effects that can be achieved by the torque control device described in the second aspect, the torque control system described in the third aspect, the chip described in the fourth aspect, the vehicle described in the fifth aspect, the computer-readable storage medium described in the sixth aspect, and the computer program product described in the seventh aspect can be referred to the beneficial effects in the first aspect and any possible design method thereof, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A schematic diagram of torque control shown in this application;

[0047] Figure 2 A schematic diagram of the structure of a vehicle shown in an embodiment of the present application;

[0048] Figure 3 The schematic diagram of the vehicle working state shown in the embodiment of the present application Figure 1 ;

[0049] Figure 4 A schematic flow chart of a torque control method according to an embodiment of the present application;

[0050] Figure 5 The schematic diagram of the vehicle working state shown in the embodiment of the present application Figure 2 ;

[0051] Figure 6 The schematic diagram of the vehicle working state shown in the embodiment of the present application Figure 3 ;

[0052] Figure 7 A schematic diagram of the structure of an electronic device shown in an embodiment of the present application;

[0053] Figure 8 This is a schematic diagram of the structure of a torque control device shown in an embodiment of the present application. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Among them, in the description of the present application, unless otherwise specified, " / " indicates that the objects associated before and after are in an "or" relationship, for example, A / B can represent A or B; "and / or" in the present application is only a description of the association relationship of the associated objects, indicating that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. And, in the description of the present application, unless otherwise specified, "multiple" refers to two or more than two. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple. In addition, in order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, the words "first", "second" and the like are used to distinguish the same items or similar items with substantially the same functions and effects. Those skilled in the art will understand that the words "first", "second" and the like do not limit the quantity and execution order, and the words "first", "second" and the like do not necessarily limit the differences. At the same time, in the embodiments of the present application, the words "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or design solutions. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete manner for ease of understanding.

[0055] In addition, the business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. A person of ordinary skill in the art can appreciate that with the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0056] The multi-motor drive system on the vehicle has the characteristics of high transmission efficiency, fast motor response, precise and controllable torque, and high redundant reliability. Through multiple motors, the driving force is distributed to each wheel, thus ensuring the vehicle's driveability and stability on low-adhesion roads and curved driving conditions.

[0057] Among them, taking the front and rear dual motor drive system in the dual motor drive system as an example, the system adopts a front-to-rear motor arrangement, with one motor arranged on the front axle of the vehicle driving the two wheels on the front axle, and one motor arranged on the rear axle driving the two wheels on the rear axle, thereby realizing front and rear dual motor four-wheel drive control, and the front axle motor and the rear axle motor independently output torque to realize torque control of the front and rear axles, and reasonably distribute the driving force or braking force between the front and rear axles through torque control, making full use of the vehicle's adhesion limit and improving vehicle stability and safety. Compared with vehicles with coaxial dual motor rear drive control, this front and rear dual motor four-wheel drive control can give full play to the advantages of four-wheel drive and use front and rear motor torque vector control to improve vehicle maneuverability and passability.

[0058] like Figure 1 As shown in FIG. 1 , when a vehicle turns, the torque transfer between the front and rear axles of the vehicle can be controlled by the vehicle's torque control to achieve the purpose of adjusting the vehicle's speed. However, the torque transfer between the front and rear axles of the vehicle will affect the vehicle's steering performance, causing the vehicle to easily experience dangerous situations such as wheel slippage.

[0059] If you want to improve the steering performance of the vehicle, you need to perform torque compensation on the front and rear axles. However, during torque compensation, the torque allocated to the front and rear axles is relatively small, resulting in a relatively small adjustment range of the front and rear axle torque. This makes it impossible to fully utilize the tires, limits the vehicle's stability and handling, makes it difficult to improve the vehicle's steering performance, and even affects the safety of vehicle driving.

[0060] A torque control method is provided in an embodiment of the present application. In this method, the yaw acceleration, lateral acceleration, original distribution torque of the front axle and original distribution torque of the rear axle of the vehicle are first obtained. Then, based on the yaw acceleration and lateral acceleration, the required torque of the whole vehicle after compensation, the first torque after compensation of the original distribution torque of the front axle and the second torque after compensation of the original distribution of the rear axle are determined. Then, based on the lateral acceleration and the required torque of the whole vehicle after compensation, the transfer torque is determined, wherein the transfer torque represents the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle. Finally, the first torque and the second torque are intervened respectively using the transfer torque.

[0061] In the above method, the original distributed torque of the front axle and the original distributed torque of the rear axle of the vehicle can be compensated respectively, and on this basis, the torque transfer is performed using the compensated vehicle demand torque, that is, the first torque and the second torque after the front and rear axles are further intervened by the transfer torque, so as to realize the torque control of the vehicle. In this method, on the basis of compensating the original distributed torque of the front and rear axles, the torque of the front axle after compensation is further transferred, and the range of the vehicle demand torque after compensation is larger, so the range of the torque that can be transferred by the front and rear axles is also larger, so that the torque transfer can increase the torque adjustment range of the front and rear axles, so that the adjusted front and rear axle torque can meet the turning requirements of the vehicle as much as possible, and improve the steering performance or ability of the vehicle. In addition, after the torque adjustment range is increased, it can also ensure that the actual torque of the front and rear axles after the transfer torque intervention is closer to the expected torque that meets the turning requirements of the vehicle, improve the controllability of the vehicle driving, and also improve the safety of the vehicle driving.

[0062] The torque control method provided in the embodiment of the present application can be applied to a vehicle (such as a four-wheel drive electric vehicle). Figure 2 As shown, the vehicle may include functional components or units such as a torque controller, a function switch, an inertial sensor, a steering wheel, an accelerator pedal, a brake pedal, a front axle motor, and a rear axle motor.

[0063] Among them, the torque controller is the main control unit, which is respectively connected to the function switch, inertial sensor, steering wheel, accelerator pedal, brake pedal, front axle motor, rear axle motor, etc. In addition, the torque controller receives signals or information from the function switch, inertial sensor, steering wheel, accelerator pedal, brake pedal, etc.

[0064] The function switch includes a physical switch on the function panel of the vehicle or a virtual switch (such as a control, etc.) in the control system (such as a central control screen function page, etc.). The function corresponding to the function switch can be turned on or off according to the user's operation. For example, after the function switch corresponding to the torque control function in the vehicle is turned on in response to the user's operation, the torque control function is in an activated or turned-on state. After that, the vehicle can execute the above torque control method when certain conditions are met.

[0065] The inertial sensor is used to obtain vehicle posture information or posture change information, and send the corresponding vehicle posture information or vehicle posture change information to the torque controller. The vehicle posture information obtained by the inertial sensor may include lateral acceleration information (or lateral jerk information) and yaw rate information (or yaw acceleration information), or may also include vehicle speed information, etc.

[0066] The steering wheel can send the current steering angle information to the torque controller, wherein the steering angle information includes information such as the steering direction and the steering angle of the steering wheel, and the torque controller can determine the wheel steering angle of the vehicle according to the steering wheel steering angle information. Alternatively, the steering angle information sent by the steering wheel can also be the wheel steering angle information converted according to the steering wheel steering angle information.

[0067] In some possible application scenarios, the torque controller can determine whether the vehicle meets the requirements for executing the above-mentioned torque control method based on the vehicle's posture information, turning angle information, etc. For example, the torque controller determines whether the vehicle starts turning based on the vehicle's posture information, determines whether the vehicle starts turning based on the turning angle information, etc.

[0068] The accelerator pedal sends acceleration intention information to the torque controller, which may be pedal stroke information, i.e., the distance the accelerator pedal moves when it is pressed, etc. The torque controller may determine the requested torque when the vehicle is driven according to the pedal stroke information. Alternatively, the accelerator pedal may first determine the requested torque information according to the pedal stroke information, and then send the requested torque information to the torque controller.

[0069] The brake pedal sends braking intention information to the torque controller, which may be pedal stroke information, brake push rod stroke information, or master cylinder pressure information, etc. The torque controller may determine the requested torque during vehicle braking or the recovery torque requested by the vehicle based on the pedal stroke information, brake push rod stroke information, or master cylinder pressure information, etc. Alternatively, the brake pedal may first determine the requested torque information based on the pedal stroke information, brake push rod stroke information, or master cylinder pressure information, etc., and send the requested torque information to the torque controller.

[0070] In some possible application scenarios, when the vehicle is turning, the torque controller can calculate the compensation torque of the vehicle's entire torque and the compensation torque of the front and rear axle torques based on the lateral acceleration information and yaw angular acceleration information of the vehicle sent by the inertial sensor. And based on the lateral acceleration and the compensated vehicle demand torque after the vehicle torque compensation, determine the transfer torque transferred from the front axle to the rear axle, or determine the transfer torque transferred from the rear axle to the front axle, so as to achieve secondary compensation of the front and rear axle torques or secondary transfer of the front and rear axle torques after the front and rear axle torque compensation.

[0071] In some possible application scenarios, when the vehicle is turning, the torque controller can also determine the requested torque of the vehicle (i.e., the above-mentioned vehicle torque) according to the pedal travel information sent by the brake pedal or the accelerator pedal, and determine the original distributed torque of the front axle and the original distributed torque of the rear axle according to the vehicle speed information and the requested torque sent by the inertial sensor. Afterwards, the torque controller compensates the original distributed torque of the front axle and the original distributed torque of the rear axle according to the determined front axle compensation torque and rear axle compensation torque, respectively, to obtain the first torque corresponding to the front and rear axles and the second torque corresponding to the rear axle, respectively.

[0072] In some other possible application scenarios, the original distributed torque of the front axle and the original distributed torque of the rear axle may not be determined by the torque controller, but may be obtained by the torque controller from other units or modules.

[0073] In some possible application scenarios, after determining the transfer torque transferred from the front axle to the rear axle, or determining the transfer torque transferred from the rear axle to the front axle, the torque controller determines the required torque after the front axle transfer torque and the required torque after the rear axle transfer torque, and sends corresponding torque control requests to the front axle motor and the rear axle motor. The front axle motor and the rear axle motor can respectively respond to the torque control requests in real time, output corresponding torques, and then change the front axle torque and the rear axle torque. For example, the front axle motor outputs the required torque of the front axle, and the rear axle motor outputs the required torque of the rear axle.

[0074] In addition, the front axle motor and the rear axle motor can also provide real-time feedback of the vehicle's current actual torque to the torque controller, and the torque controller can also determine whether the vehicle is currently in a driving state and a braking state (or a recovery state) based on the actual torque.

[0075] See also Figure 3 As shown in (a) in the figure, when the vehicle starts to turn, it needs to apply centripetal force to the inside of the curve, thereby generating lateral acceleration to the inside, indicating that the lateral jerk of the lateral acceleration change rate is positive, and during the turning process, the yaw angle (the angle of rotation of the vehicle around the Z axis perpendicular to the ground) increases, and the yaw angular velocity also increases, indicating that the yaw acceleration of the yaw velocity change rate is positive.

[0076] See also Figure 3 As shown in (b) in the figure, during the process of the vehicle returning to center at the end of a turn, the centripetal force applied to the inner side of the curve decreases, and the lateral acceleration toward the inner side decreases, indicating that the lateral jerk of the lateral acceleration change rate is a negative value. In addition, during the process of the vehicle returning to center, the yaw angle decreases, and the yaw angular velocity also decreases, indicating that the yaw angular acceleration of the yaw angular velocity change rate is a negative value.

[0077] The torque controller can regard the steering process and the returning process of the vehicle as the steady-state working process of the vehicle, that is, the steering state and the returning state of the vehicle are steady-state.

[0078] See also Figure 3 As shown in (c) in the figure, the vehicle is prone to "pushing the head" and "swinging the tail" during the turning process. Among them, excessive braking strength when the vehicle is turning, excessive adjustment of the turning direction, unreasonable load (load) distribution, changes in the road environment, etc. can all cause "pushing the head", that is, understeering. In the "pushing the head" situation, although the front wheels of the vehicle turn according to the expected route when turning, they do not follow the expected route due to insufficient grip, but are driven by the body to slip. In this case, the vehicle's yaw angular velocity decreases, indicating that the yaw acceleration of the yaw angular velocity change rate is a negative value, while the vehicle's lateral acceleration increases, indicating that the lateral jerk of the lateral acceleration change rate is a positive value.

[0079] See also Figure 3 As shown in (d) in the figure, the vehicle speed is too fast when turning, the turning direction is adjusted too much, etc., which can cause "tail swing", that is, oversteering. In the case of "tail swing", the rear wheels of the vehicle have insufficient grip and do not turn according to the expected turning angle, but turn a greater angle. In this case, the yaw rate of the vehicle increases, indicating that the yaw acceleration of the yaw rate change rate is a positive value, while the lateral acceleration of the vehicle decreases, indicating that the lateral jerk of the lateral acceleration change rate is a negative value.

[0080] The torque controller can regard the vehicle's "pushing head" and "swinging tail" states as the vehicle's unstable state.

[0081] Based on the above content, the torque controller can determine the current working state of the vehicle according to the positive and negative conditions of the values ​​of the lateral jerk and the yaw angular acceleration. For example, when the values ​​of the lateral jerk and the yaw angular acceleration are both negative values, the torque controller can determine that the vehicle is in a steady state, and when the values ​​of the lateral jerk and the yaw angular acceleration are both positive values, the torque controller can determine that the vehicle is in a steady state.

[0082] Afterwards, the torque controller determines the torque control strategy according to the working state of the vehicle, and determines the required torque of the front axle and the required torque of the rear axle after the secondary torque transfer according to the torque control strategy. The torque control strategy includes the compensation strategy of the vehicle's whole vehicle torque (or requested torque) and the transfer strategy of the front and rear axle torque.

[0083] The vehicle can accelerate or decelerate under different working conditions. Accordingly, the vehicle torque (or requested torque) that the torque controller can obtain may include driving torque or recovery torque (or braking torque). Therefore, the compensation strategy for the vehicle torque (or requested torque) includes reducing the driving torque, increasing the driving torque, reducing the recovery torque, increasing the recovery torque, etc. The transfer strategy includes transferring the transfer torque from the rear axle to the front axle, transferring the transfer torque from the front axle to the rear axle, etc. Exemplarily, when the vehicle is in a steering state, if the vehicle requests the driving torque, the torque controller reduces the driving torque and transfers the transfer torque from the front axle to the rear axle, thereby reducing the front axle torque, changing the utilization rate of the front axle tire, reducing the front wheel slip, and avoiding understeering; if the vehicle requests the recovery torque, the torque controller increases the recovery torque and transfers the transfer torque from the front axle to the rear axle, which can also reduce the front axle torque, improve the grip of the front axle tire, and reduce the understeering situation.

[0084] When the vehicle is in the return state, if the vehicle requests driving torque, the torque controller increases the driving torque and transfers the torque from the rear axle to the front axle, thereby reducing the rear axle torque, changing the rear axle tire utilization, reducing rear axle slippage, and avoiding oversteer; if the vehicle requests recovery torque, the torque controller reduces the recovery torque and transfers the torque from the rear axle to the front axle, which can also reduce oversteer.

[0085] When the vehicle is in the "push head" state, regardless of whether the vehicle requests driving torque or recovery torque, the torque controller will reduce the torque and transfer the torque from the front axle to the rear axle, thereby reducing the front axle torque, changing the front axle tire utilization, reducing front wheel slippage, and reducing the impact of understeer.

[0086] When the vehicle is in a "drifting" state, regardless of whether the vehicle requests driving torque or recovery torque, the torque controller will reduce the torque and transfer the torque from the rear axle to the front axle, thereby reducing the rear axle torque, changing the rear axle tire utilization, reducing rear axle slippage, and reducing the impact of oversteer.

[0087] In some possible application scenarios, after obtaining the required torque of the front and rear axles after the secondary torque transfer, the torque controller can also limit the required torque to avoid excessive adjustment or change of the torque behind the front axle, which affects the safe driving of the vehicle. The limiting process can include gradient processing and filtering processing, etc., to ensure the controllability of the vehicle.

[0088] In some possible application scenarios, the process of the torque controller obtaining the original torque distribution of the axle and the original torque distribution of the rear axle can be regarded as a pre-processing process, while the process of limiting, gradient processing, filtering, etc. of the required torque of the front and rear axles can be regarded as a post-processing process.

[0089] Combined with the above content, it can be known that the torque control method in the embodiment of the present application can first compensate the original distributed torque of the front axle and the original distributed torque of the rear axle of the vehicle respectively, and on this basis, the torque transfer is performed using the compensated vehicle demand torque, that is, the first torque and the second torque after the front and rear axles are further intervened by the transfer torque, so as to realize the torque control of the vehicle. In this method, on the basis of compensating the original distributed torque of the front and rear axles, the torque of the front axle after compensation is further transferred. The range of the demanded torque of the whole vehicle after compensation is larger, so the range of the torque that can be transferred by the front and rear axles is also larger, so that the torque transfer can increase the torque adjustment range of the front and rear axles, so that the adjusted front and rear axle torque can meet the turning requirements of the vehicle as much as possible, and improve the steering performance or ability of the vehicle. Moreover, after the torque adjustment range is increased, it can also ensure that the actual torque of the front and rear axles after the transfer torque intervention is closer to the expected torque that meets the turning requirements of the vehicle, improve the controllability of the vehicle driving, and also improve the safety of the vehicle driving.

[0090] In addition, in the above method, the curvature of the curve is not used, so there is no need to predict the curvature of the curve based on data collected by road preview sensors and other equipment. This can also reduce the complexity of the torque control method and reduce the difficulty of implementation. Moreover, the above method not only performs separate torque compensation for the front and rear axle torques, but on this basis, it can further transfer the torque of the front axle to the rear axle, or the torque of the rear axle to the front axle according to the working state of the vehicle. Especially in the "pushing head" and "tail drifting" states, it can well ensure the grip of the front and rear axle tires and reduce the impact of understeer or oversteer on the vehicle.

[0091] Take the torque control method in the embodiment of the present application applied to the vehicle when turning as an example, see Figure 4 As shown, the method may include the following steps S401-S404.

[0092] S401. The vehicle obtains yaw angular acceleration, lateral acceleration, original distributed torque of the front axle, and original distributed torque of the rear axle.

[0093] The yaw acceleration is related to the yaw angle of the vehicle, and represents the rate of change of the yaw angle over time. Specifically, it can be obtained by taking the derivative of the yaw angle of the vehicle. Also, the vehicle can determine the lateral jerk of the vehicle according to the lateral acceleration. The lateral jerk represents the rate of change of the lateral acceleration. Specifically, it can be obtained by taking the derivative of the lateral acceleration of the vehicle.

[0094] In some embodiments, the original front axle torque and the original rear axle torque may be determined when the vehicle executes the torque control method. For example, when the vehicle obtains the original front axle torque and the original rear axle torque, the vehicle may first obtain the current pedal travel information and the current vehicle speed information. The pedal travel information may include the travel information of the brake pedal or the travel information of the accelerator pedal, which is used to indicate the distance moved when the brake pedal is pressed or the distance moved when the accelerator pedal is pressed.

[0095] After that, the vehicle determines the vehicle's requested torque Tq based on the pedal travel information. Req . In some possible application scenarios, since the pedal travel information indicates the distance the pedal moves when it is pressed, the vehicle can convert the pedal's movement distance into the corresponding requested torque. When the pedal travel information indicates the travel information of the accelerator pedal, it indicates that the vehicle requests acceleration, and the requested torque determined by the vehicle may be the driving torque; when the pedal travel information indicates the travel information of the brake pedal, it indicates that the vehicle requests deceleration or braking, and the requested torque determined by the vehicle may be the braking torque or the recovery torque.

[0096] Determine the requested torque Tq Req After that, the vehicle obtains the requested torque Tq Req The original torque distribution rate k corresponding to the vehicle speed information 0 , and, according to the requested torque Tq Req and the original torque distribution rate k 0 , determine the original distributed torque Tq of the front axle F0 and the original torque distributed to the rear axle Tq R0 The requested torque may represent the requested torque of the vehicle. When driving the vehicle, the requested torque of the vehicle may be allocated to the front axle and the rear axle respectively, so as to apply driving force or braking force to the front axle and the rear axle respectively to achieve acceleration or deceleration of the vehicle. In addition, the original torque distribution rate may represent the proportion of the torque allocated to the front axle in the total requested torque of the vehicle.

[0097] In some possible application scenarios, the vehicle can determine a preset table based on the motor capacity and motor efficiency of the front axle motor and the rear axle motor, etc. The preset table stores the requested torque Tq Req -Vehicle speed-Original torque distribution ratio k 0 The corresponding relationship is that, in this preset table, the vehicle can be driven according to a request torque Tq Req and a vehicle speed, determine the corresponding original torque distribution rate k 0 .

[0098] It is understandable that the original front axle torque and the original rear axle torque are torques that support normal driving of the vehicle. The original front axle torque and the original rear axle torque can be preset by the vehicle and determine the handling characteristics of the vehicle under the nominal state. If the torque control method in the embodiment of the present application is not executed, the vehicle will also obtain the original front axle torque and the original rear axle torque, and control the front axle motor to output the original front axle torque, and control the rear axle motor to output the original rear axle torque, so that the vehicle can travel according to the current driving needs.

[0099] And, exemplarily, the front axle original distribution torque Tq F0 It can be determined according to the following formula (1), and the original distributed torque Tq of the rear axle is R0 It can be determined according to the following formula (2).

[0100] Tq F0 =Tq Req *k 0 (1)

[0101] Tq R0＝ Tq Req *(1-k 0 ) (2)

[0102] S402: The vehicle determines the compensated vehicle required torque, the first torque after compensating the original distributed torque of the front axle, and the second torque after compensating the original distributed torque of the rear axle according to the yaw angular acceleration and the lateral acceleration.

[0103] In some embodiments, in order to reduce understeering or oversteering when the vehicle turns, the vehicle can also obtain the yaw angular acceleration when turning. and lateral acceleration a Y , determine the vehicle's full vehicle compensation torque Tq Ctl . Vehicle compensation torque Tq Ctl The requested torque Tq for the vehicle Req Compensation is performed, for example, when the requested torque Tq Req The vehicle compensation torque Tq is superimposed on the Ctl Among them, if the vehicle compensation torque Tq Ctl If the vehicle compensation torque Tq is negative, it means that the requested torque of the vehicle is reduced. Ctl If it is a positive value, it means that the requested torque of the whole vehicle is increased. And, the whole vehicle compensation torque Tq is used Ctl For the requested torque Tq Req After compensation, the vehicle's compensated vehicle demand torque Tq can be obtained Req1 .

[0104] Exemplarily, the vehicle compensation torque Tq CtlAnd the vehicle demand torque after compensation Tq Req1 It can be determined according to the following formula (3).

[0105]

[0106] Among them, C ωx is the gain coefficient for torque calculation (the coefficient is set as a constant for linear gain and as a function related to vehicle posture parameters for nonlinear gain), μ is the current reference road adhesion coefficient, g is 9.8 m / s^2, [Tq min ,Tq max ] is the preset vehicle compensation torque value range.

[0107] In the above-mentioned compensation process for the requested torque of the vehicle, the yaw angular acceleration of the vehicle when turning To a certain extent, it can characterize the working state of the vehicle when turning, and the yaw angular acceleration The positive or negative value can affect the vehicle's vehicle compensation torque Tq when turning. Ctl The positive or negative value of the value affects the type of torque compensation for the vehicle's requested torque. For example, when When the vehicle compensation torque Tq Ctl is a negative value, and the vehicle demand torque after compensation is Tq Req1 Decrease, indicating that the requested torque is reduced; when When the vehicle compensation torque Tq Ctl is a positive value, and the vehicle demand torque after compensation is Tq Req1 An increase indicates that the requested torque is being increased.

[0108] In addition, when turning, the yaw angular acceleration Indicates that the vehicle's understeer tendency is increasing. In this case, the requested torque of the vehicle can be reduced, and the front axle load and rear axle load can be increased to improve the grip of the front axle tire and improve the understeer situation. It indicates that the vehicle's tendency to oversteer is increasing. In this case, the requested torque of the vehicle can be increased to reduce the load on the front axle, increase the load on the rear axle, improve the grip of the rear axle tire, and improve the oversteer situation.

[0109] In some embodiments, regardless of the requested torque Tq Req How to compensate (increase torque or reduce torque), the vehicle will compensate the torque Tq of the whole vehicle according to a certain ratio Ctl Distribute to the front and rear axles, thereby achieving the purpose of changing the load on the front and rear axles. Ctl Distributing to the front axle and the rear axle can also be understood as compensating the original distributed torque of the front axle and compensating the original distributed torque of the rear axle.

[0110] Furthermore, the vehicle can first be based on the yaw angular acceleration Determine the compensation torque distribution rate k 1 . Compensation torque distribution rate k 1 Indicates the vehicle compensation torque Tq Ctl The proportion of the front axle in the compensation torque distribution rate k 1 and vehicle compensation torque Tq Ctl , respectively determine the front axle compensation torque Tq of the vehicle CtF and rear axle compensation torque Tq CtR . Then use the front axle compensation torque Tq CtF Original distribution torque Tq to the front axle F0 Compensation is performed to obtain the first torque Tq of the front axle after compensation F1 , for example, the original distributed torque Tq on the front axle F0 On the basis of the front axle compensation torque Tq CtF , and, using the rear axle compensation torque Tq CtR Original distribution torque Tq to the rear axle R0 Compensation is performed to obtain the second torque Tq of the rear axle after compensation R1 , for example, the original distribution torque Tq at the rear axle R0 On the basis of the superimposed rear axle compensation torque Tq CtR .

[0111] And, exemplarily, the compensation torque distribution ratio k 1 It can be determined according to the following formula (4).

[0112]

[0113] Among them, C ω is the gain coefficient of the compensation torque distribution. Among them, the yaw angular acceleration The bigger, or It can indicate that the understeering tendency of the vehicle increases. In this case, the compensation torque distribution rate k 1 The smaller the yaw angular acceleration is, the less the vehicle compensation torque is distributed to the front axle, thereby increasing the load on the front axle, improving the grip of the front axle tire, and improving understeer. The smaller, or It can indicate that the tendency of vehicle oversteering increases. In this case, the compensation torque distribution rate k 1 The larger it is, the less the vehicle compensation torque is distributed to the rear axle, thereby increasing the load on the rear axle, improving the grip of the rear axle tire, and improving oversteer.

[0114] and, exemplarily, the front axle compensation torque Tq CtFand rear axle compensation torque Tq CtR It can be determined according to the following formula (5).

[0115]

[0116] For example, the first torque Tq F1 and the second torque Tq R1 It can be determined according to the following formula (6).

[0117]

[0118] S403: The vehicle determines a transfer torque according to the lateral acceleration and the compensated vehicle required torque.

[0119] The transfer torque refers to the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle.

[0120] In some embodiments, the vehicle can be adjusted according to the lateral acceleration a Y , determine the lateral jerk of the vehicle After that, according to the lateral jerk Determine the torque transfer rate k 2 Among them, the torque transfer rate k 2 Indicates the torque Tq transferred from the front axle to the rear axle or from the rear axle to the front axle Trans The vehicle demand torque after compensation is Tq Req1 proportion.

[0121] And, the vehicle is based on the torque transfer rate k 2 And the vehicle demand torque after compensation Tq Req1 , determine the transfer torque Tq Trans .

[0122] and, illustratively, the torque transfer rate k 2 and transfer torque Tq Trans It can be determined according to the following formula (7).

[0123]

[0124] Among them, C ay is the gain coefficient for calculating the torque transfer coefficient (a linear gain is obtained when it is set as a constant, or a nonlinear gain is obtained when it is set as a function related to the vehicle posture parameters), [k 2min ,k 2max ] is the preset torque transfer rate value range.

[0125] In the above process of determining the transfer torque, the lateral jerk of the vehicle when turning To a certain extent, it affects the torque transfer rate k 2The size of the torque transfer rate k 2 The size of the transfer torque Tq Trans And, the lateral jerk To a certain extent, it can also indicate the state of the vehicle when turning, the lateral jerk The positive and negative value of the transfer torque Tq Trans For example, when When the lateral acceleration of the vehicle increases, the understeering tendency of the vehicle increases. In this case, the transfer torque Tq Trans Transfer from the front axle to the rear axle, reduce the front axle torque, increase the rear axle torque, change the front and rear axle tire utilization, reduce the front wheel slip, and further reduce the occurrence of understeer; When the lateral acceleration of the vehicle decreases, the oversteering tendency of the vehicle increases. In this case, the transfer torque Tq Trans Transfer from the rear axle to the front axle, increase the front axle torque, reduce the rear axle torque, change the front and rear axle tire utilization, reduce rear wheel slippage, and reduce oversteer.

[0126] S404: The vehicle determines a first required torque of a front axle of the vehicle according to the transfer torque and the first torque, and determines a second required torque of a rear axle of the vehicle according to the transfer torque and the second torque.

[0127] The transfer torque is used to intervene in the first torque and the second torque respectively, and the intervention method can be expressed as superimposing or reducing the transfer torque on the basis of the first torque, or reducing or superimposing the transfer torque on the basis of the second torque. In addition, whether the first torque is superimposed on the torque and whether the second torque is superimposed on the torque are determined according to the transfer direction of the transfer torque.

[0128] For example, when the transfer torque Tq Trans When the transfer torque Tq is transferred from the front axle to the rear axle, it means that the first torque is reduced, that is, the transfer torque is reduced on the basis of the first torque, and at the same time, the second torque is increased, that is, the transfer torque is superimposed on the basis of the second torque; when the transfer torque Tq Trans When the torque is transferred from the rear axle to the front axle, it means that the first torque increases, that is, the transferred torque is superimposed on the first torque, and at the same time, the second torque decreases, that is, the transferred torque is reduced on the basis of the second torque.

[0129] The above torque transfer process is equivalent to performing a secondary torque transfer using the vehicle's compensated vehicle demand torque on the basis of compensating the original front axle distribution torque and the original rear axle distribution torque respectively, that is, using the transfer torque to further intervene in the first torque and the second torque after the front and rear axles are compensated. The first compensation process of the original front and rear axles distribution torque is based on the vehicle compensation torque, and the secondary torque transfer process is based on the compensated vehicle demand torque. The previous compensation of the original front and rear axles distribution torque can initially achieve the purpose of changing the load of the front and rear axles and ensuring the steering performance of the vehicle when the vehicle is understeering or oversteering, and the secondary torque transfer can further change the torque of the front and rear axles while considering the vehicle demand torque, thereby better improving the understeering or oversteering situation.

[0130] In some embodiments, when the transfer torque is transferred from the front axle to the rear axle, the vehicle is at a first torque Tq F1 and above to reduce the transfer torque Tq Trans , get the first required torque Tq F2 , and, at the second torque Tq R1 The superimposed transfer torque Tq Trans , obtain the second required torque Tq R2 .

[0131] And, exemplarily, the first required torque Tq F2 and the second required torque Tq R2 It can be determined according to the following formula (8).

[0132]

[0133] In other embodiments, when the transfer torque is transferred from the rear axle to the front axle, the vehicle is at a first torque Tq F1 And the superimposed transfer torque Tq Trans , get the first required torque Tq F2 , and, at the second torque Tq R1 Reduce the transfer torque Tq Trans , obtain the second required torque Tq R2 .

[0134] And, exemplarily, the first required torque Tq F2 and the second required torque Tq R2 It can be determined according to the following formula (9).

[0135]

[0136] In some embodiments, when the vehicle is turning, it can be in different working states at different stages. And the working state can be determined by the aforementioned lateral jerk. and yaw angular acceleration For example, see Figure 5 As shown in the figure, the working states of the vehicle when turning include steering state, return state, head-pushing state and tail-swinging state. is greater than zero, and the lateral jerk When it is greater than zero, as the vehicle's turning angle gradually builds, the lateral acceleration and yaw rate both increase, and the working state at this time is the steering state; when the yaw rate is Less than zero, and the lateral jerk When the lateral acceleration and yaw rate decrease as the vehicle turns gradually back to the center, the working state is the return state. Less than zero, and the lateral jerk When it is greater than zero, the lateral acceleration of the vehicle increases and the yaw rate decreases, indicating that the lateral force increases and the steering curvature decreases, and the front axle tire has poor grip. At this time, the working state is the push head state; when the yaw rate is greater than zero, and the lateral jerk When it is less than zero, the vehicle's lateral acceleration decreases and the yaw angular velocity increases, indicating that the lateral force decreases and the steering curvature increases, and the rear axle tire has poor grip. At this time, the working state is a tail-swinging state.

[0137] Since the vehicle will have the above-mentioned different working states when turning, in order to ensure that the vehicle can maintain good steering performance in each working state, in some embodiments, the vehicle can also obtain the current working state of the vehicle, and determine the torque control strategy according to the working state, and, according to the torque control strategy, use the transfer torque and the first torque to determine the first required torque, and use the transfer torque and the second torque to determine the second required torque.

[0138] And, in some possible application scenarios, the working state of the vehicle can be divided into steady state and unstable state. The steady state further includes Figure 5 The turning state and the return state shown in the figure, and the unstable state further includes Figure 5 The push head state and tail swing state shown in .

[0139] Refer to Table 1 below. When the vehicle is in a steady state, when the yaw angular acceleration The value and lateral jerk If the values ​​of are all positive, the vehicle is in a steady-state steering state. In this case, the vehicle can further determine the corresponding torque control strategy according to the type of requested torque.

[0140] The type of torque requested can be determined according to the state of the accelerator pedal or brake pedal of the vehicle, and the state of the accelerator pedal or brake pedal can be determined according to the stroke information of the accelerator pedal and the stroke information of the brake pedal, for example, the accelerator pedal is determined to be pressed or the brake pedal is released according to the stroke information of the pedal, or the brake pedal is determined to be pressed or the accelerator pedal is released according to the stroke information of the pedal. When the accelerator pedal is pressed or the brake pedal is released, it means that the vehicle requests acceleration, and at this time, the type of torque requested by the vehicle is driving torque; when the brake pedal is pressed or the accelerator pedal is released, it means that the vehicle requests deceleration or braking, and at this time, the type of torque requested by the vehicle is recovery torque. And the torque control strategy includes a compensation strategy for the requested torque and a transfer strategy for the transferred torque.

[0141] Exemplarily, when the requested torque is the driving torque, the torque control strategy determined by the vehicle includes a torque reduction compensation operation for the requested torque and a transfer torque from the front axle to the rear axle. When the requested torque is the recovery torque, the torque control strategy determined by the vehicle includes a torque increase compensation operation for the requested torque and a transfer torque from the front axle to the rear axle.

[0142] In this way, when the vehicle itself is in a stable steering state, in order to maintain the current stable state of the vehicle, the driving torque requested by the vehicle is reduced, and the torque compensated to the front and rear axles will reduce the driving torque of the front and rear axles, so that the vehicle load (or vertical load) moves forward, and the front axle tire adhesion, grip, etc. are improved; and the transfer torque is transferred from the front axle to the rear axle, which can also reduce the front axle torque, change the front axle tire utilization rate, reduce the front wheel slip, and reduce the occurrence of understeering. Alternatively, when the vehicle itself is in a stable steering state, in order to maintain the current steering state of the vehicle, the recovery torque requested by the vehicle is increased, which can also be equivalent to reducing the driving torque. At the same time, the torque compensated to the front and rear axles will increase the recovery torque of the front and rear axles, and can also move the vehicle load (or vertical load) forward, improve the front axle tire adhesion, grip, etc.; and the transfer torque is transferred from the front axle to the rear axle, which can also reduce the front axle torque, change the front axle tire utilization rate, reduce the front wheel slip, and reduce the occurrence of understeering.

[0143] When the vehicle is in a steady state, the yaw angular acceleration The value and lateral jerk If the values ​​of are all negative, the vehicle is in a steady-state return state. In this case, the vehicle can further determine the corresponding torque control strategy according to the type of requested torque.

[0144] Exemplarily, when the requested torque is the driving torque, the torque control strategy determined by the vehicle includes performing a torque-up compensation operation on the requested torque and transferring the transfer torque from the rear axle to the front axle. When the requested torque is the recovery torque, the torque control strategy determined by the vehicle includes performing a torque-down compensation operation on the requested torque and transferring the transfer torque from the rear axle to the front axle.

[0145] Thus, when the vehicle itself is in a stable return state, in order to maintain the current stable state of the vehicle, the requested drive torque of the vehicle is increased, and the torque compensated to the front and rear axles will increase the drive torque of the front and rear axles, so that the vehicle load (or vertical load) moves backward, and the adhesion and grip of the rear axle tire are improved; and the transfer torque is transferred from the rear axle to the front axle, which can also reduce the rear axle torque, change the tire utilization rate, reduce the rear wheel slip, and reduce the occurrence of oversteering. Alternatively, when the vehicle itself is in a stable return state, in order to maintain the current stable state of the vehicle, the requested recovery torque of the vehicle is reduced, which can also be equivalent to increasing the drive torque. At the same time, the torque compensated to the front and rear axles will reduce the recovery torque of the front and rear axles, so that the vehicle load (or vertical load) moves backward, and the adhesion and grip of the rear axle tire are improved; and the transfer torque is transferred from the rear axle to the front axle, which can also reduce the rear axle torque, change the tire utilization rate, reduce the rear wheel slip, and reduce the occurrence of oversteering.

[0146] And, corresponding to the torque control in the steady state of the vehicle, the vehicle can achieve the following when turning: Figure 6 The overall stable driving process shown.

[0147] Figure 6 In the figure, the solid arrow on the right side of the vehicle indicates the first demand request Tq allocated to the front axle by the torque control method in the embodiment of the present application. F2 , and the second required torque Tq distributed to the rear axle R2 , the black arrow at the center of the vehicle represents the lateral acceleration a of the vehicle Y , the lateral acceleration a Y is the sum of the lateral accelerations of the front and rear axles. Figure 6 The coordinate diagram at the center is the phase diagram of the vehicle motion state changing with the acceleration friction circle, and the horizontal axis represents the longitudinal acceleration a X , positive values ​​indicate acceleration, negative values ​​indicate deceleration, and the vertical axis indicates the lateral acceleration a Y , the positive direction is pointing to the center of curvature. Figure 6 The numbers (0)-(8) in the figure represent different positions of the vehicle.

[0148] (0)-(1) indicates the pre-curve stage, when the vehicle is traveling in a straight line and requests deceleration based on the driver pressing the deceleration pedal;

[0149] (1)-(2)-(3) represent the steering phase. As the yaw angle increases, the vehicle performs torque reduction operation, and as the lateral acceleration increases, more torque is allocated to the rear axle to reduce the impact of the vehicle's current understeering and improve the steering sensitivity. Furthermore, if the yaw angle increases while the lateral acceleration decreases, the vehicle is in a drifting state. At this time, the vehicle performs torque reduction operation and allocates more torque to the front axle, which can also alleviate the impact of the drifting state.

[0150] (3)-(4)-(5) represents the stable cornering stage. In this stage, there is no load transfer and front and rear axle torque distribution in the vehicle, and the vehicle maintains stable steering performance;

[0151] (5)-(6)-(7) represent the return-to-center stage. As the yaw angle decreases, the vehicle performs a torque-up operation, and as the lateral acceleration decreases, more torque is allocated to the front axle to increase the impact of the vehicle's current oversteering and improve the stability of the vehicle's return-to-center state. Furthermore, if the yaw angle decreases while the lateral acceleration increases, the vehicle is in a push-head state. At this time, the vehicle performs a torque-down operation and allocates more torque to the rear axle, which can also alleviate the impact of the push-head state.

[0152] (7)-(8) indicate the post-curve phase, where the vehicle is traveling in a straight line and acceleration is requested by the driver pressing the accelerator pedal.

[0153] As shown in Table 1, when the vehicle is in an unstable state, when the yaw angular acceleration Negative values ​​and lateral jerk If the value of is positive, the vehicle is in a push-head state in an unstable state. In this case, the vehicle can further determine the corresponding torque control strategy according to the type of requested torque.

[0154] Exemplarily, when the requested torque is the driving torque, the torque control strategy determined by the vehicle includes a torque reduction compensation operation for the requested torque, and transferring the transfer torque from the front axle to the rear axle. When the requested torque is the recovery torque, the torque control strategy determined by the vehicle includes a torque reduction compensation operation for the requested torque, and transferring the transfer torque from the front axle to the rear axle.

[0155] In this way, when the vehicle is in a push-head state, the drive torque requested by the vehicle is reduced, and the torque compensated to the front and rear axles will reduce the drive torque of the front and rear axles, avoiding excessive speed when the vehicle turns, and at the same time, the vehicle load is moved forward to improve the front axle tire adhesion, grip, etc.; and the transfer torque is transferred from the front axle to the rear axle, which can also reduce the front axle torque, change the tire utilization rate, reduce the front wheel slip, and reduce the occurrence of push-head situations. Alternatively, when the vehicle is in an unstable state, the recovery torque requested by the vehicle is reduced, which is equivalent to increasing the drive torque, and the torque compensated to the front and rear axles will reduce the recovery torque of the front and rear axles, while the drive torque is increased, so that the vehicle load is moved forward, improving the front axle tire adhesion, grip, etc.; and the transfer torque is transferred from the front axle to the rear axle, which can also reduce the front axle torque, change the tire utilization rate, reduce the front wheel slip, and reduce the occurrence of push-head situations.

[0156] When the vehicle is in an unstable state, when the yaw angular acceleration The value is positive and the lateral jerk If the value of is negative, the vehicle is in a drifting state in an unstable state. In this case, the vehicle can further determine the corresponding torque control strategy according to the type of requested torque.

[0157] Exemplarily, when the requested torque is the driving torque, the torque control strategy determined by the vehicle includes a torque reduction compensation operation for the requested torque, and transferring the transfer torque from the front axle to the rear axle. When the requested torque is the recovery torque, the torque control strategy determined by the vehicle includes a torque reduction compensation operation for the requested torque, and transferring the transfer torque from the front axle to the rear axle.

[0158] In this way, when the vehicle is in a tail-pushing state, the driving torque requested by the vehicle is reduced, and the torque compensated to the front and rear axles will reduce the driving torque of the front and rear axles, thereby avoiding excessive speed when the vehicle is returning to the center position, and at the same time, the vehicle load is shifted backwards, improving the adhesion and grip of the rear axle tires, etc.; and the transfer torque is transferred from the rear axle to the front axle, which can also reduce the rear axle torque, change the tire utilization rate, reduce the rear wheel slip, and reduce the occurrence of tail swing. Alternatively, when the vehicle is in an unstable state, the recovery torque requested by the vehicle is reduced, which is equivalent to the driving torque increase, and the torque compensated to the front and rear axles will reduce the recovery torque of the front and rear axles, while the driving torque is increased, so that the vehicle load is shifted backwards, improving the adhesion and grip of the rear axle tires, etc.; and the transfer torque is transferred from the rear axle to the front axle, which can also reduce the rear axle torque, change the tire utilization rate, reduce the rear wheel slip, and reduce the occurrence of tail swing.

[0159] Table 1

[0160]

[0161] It can be understood that when the vehicle is in the above-mentioned steady state, the total torque requested by the vehicle (i.e., the requested torque) can be compensated by increasing or decreasing the torque to change the load of the front and rear axles. For example, the requested driving torque is reduced in the steering state, and the original distributed torque allocated to the front and rear axles is also the driving torque, and the driving torque allocated to the front axle is reduced more, and the driving torque allocated to the rear axle is reduced less, thereby increasing the grip of the front axle tire. When the unexpected understeer of the vehicle is more obvious, the torque reduction is greater; and, the requested driving torque is increased in the return state, which can also change the load of the front and rear axles, and the original distributed torque allocated to the front and rear axles is also the driving torque, and the driving torque allocated to the front axle is increased more, and the driving torque allocated to the rear axle is increased less, thereby increasing the grip of the rear axle tire. When the unexpected oversteer of the vehicle is more obvious, the torque increase is greater.

[0162] When the vehicle is in the above-mentioned unstable state, the total torque requested by the vehicle (i.e., the requested torque) can be reduced, and the original distributed torques allocated to the front and rear axles are also reduced. The more obvious the unexpected understeer or oversteer of the vehicle is, the more the torque is reduced. However, after the original distributed torques of the front and rear axles are reduced and the torque is transferred, the torque of the front axle motor and the torque of the rear axle motor do not exceed zero, that is, the positive and negative ranges of the compensated front axle motor and rear axle motor torques are not changed, thereby ensuring that the vehicle will not be forcibly changed in working state under the action of torque control, affecting the safety of vehicle driving.

[0163] For example, if the vehicle requests driving torque, then after torque control to reduce the driving torque and torque transfer, the minimum torque output by the front and rear axle motors is reduced to 0 and cannot be less than 0; and if the vehicle requests recovery torque, then after torque control to reduce the recovery torque and torque transfer, the maximum value of the torque output by the front and rear axle motors is 0 and cannot be greater than 0.

[0164] When the vehicle requests driving torque and requesting recovery torque, vehicle torque reduction refers to a decrease in the absolute value of the torque, that is, approaching zero torque is a reduction, and torque increase refers to an increase in the absolute value of the torque, that is, moving away from zero torque is a torque increase.

[0165] In other embodiments, the vehicle can further determine the type of requested torque based on the sum of the actual torques output by the front and rear axle motors. For example, the actual torques output by the front and rear axles can be positive or negative, with a positive value indicating a driving torque and a negative value indicating a recovery torque. If the sum of the actual torques output by the front and rear axle motors is a positive value, it indicates that the vehicle is requesting a driving torque; if the sum of the actual torques output by the front and rear axle motors is a negative value, it indicates that the vehicle is requesting a recovery torque.

[0166] The torque control strategy can be determined according to the working state of the vehicle. After the torque control strategy is determined, the vehicle uses the transfer torque to intervene in the first torque and the second torque based on the torque control strategy, thereby obtaining the first required torque and the second required torque. And, it can be understood that the vehicle can control the front axle motor to output the first required torque and the rear axle motor to output the second required torque, thereby realizing the torque control of the front and rear axle motors, changing the load and torque of the front and rear axles, and improving the steering performance of the vehicle when turning.

[0167] The torque control method of the embodiment of the present application can first compensate the original distributed torque of the front axle and the original distributed torque of the rear axle of the vehicle respectively, and then use the compensated vehicle demand torque to transfer the torque, that is, use the transferred torque to further intervene the first torque and the second torque after the front and rear axles are compensated, so as to achieve the torque control of the vehicle. In this method, on the basis of compensating the original distributed torque of the front and rear axles, the torque of the front axle after compensation is further transferred. The range of the demanded torque of the vehicle after compensation is large, so the range of the torque that can be transferred by the front and rear axles is also large, so that the torque transfer can increase the torque adjustment range of the front and rear axles, so that the adjusted front and rear axle torque can meet the turning requirements of the vehicle as much as possible, and improve the steering performance or ability of the vehicle. Moreover, after the torque adjustment range is increased, it can also ensure that the actual torque of the front and rear axles after the transfer torque intervention is closer to the expected torque that meets the turning requirements of the vehicle, improve the controllability of the vehicle driving, and also improve the safety of the vehicle driving.

[0168] In addition, the above-mentioned torque control method can also divide the vehicle's working state into steady state (such as steering, returning to the center state), unstable state (such as pushing the head, drifting the tail) and other working states in more detail. Different torque control strategies can be adopted for different working states, thereby covering a variety of steady and unstable state situations, so that the vehicle can perform torque control well in different working states, reduce the impact of understeer or oversteer, and ensure the vehicle's controllability and stability.

[0169] In addition, in the above method, there is no need to predict the curvature of the curve based on the data collected by the road preview sensor and other equipment, which can also reduce the complexity of the torque control method and reduce the difficulty of implementation. Moreover, the above method not only performs separate torque compensation for the front and rear axle torques, but on this basis, it can further transfer the torque of the front axle to the rear axle, or transfer the torque of the rear axle to the front axle according to the working state of the vehicle. For example, when the vehicle is in a steering state, the front and rear torques are transferred to the rear axle. On the basis of reducing the front axle torque and improving the grip of the front axle tire, the tire utilization rate of the front axle is further changed, reducing the front wheel slippage of the vehicle when turning, and improving the steering performance of the vehicle.

[0170] In some embodiments, the vehicle obtains the first required torque Tq F2 and the second required torque Tq R2 After that, the front axle load (or load) m of the vehicle can also be obtained. F and rear axle load (or load) m R , and according to the lateral acceleration a Y and front axle load m F , determine the front axle torque limit range of the vehicle, and according to the lateral acceleration a Y and rear axle load m R , determine the rear axle torque limit range of the vehicle. The front axle torque limit range is used to determine the first required torque Tq F2 The rear axle torque limit range is used to limit the second required torque Tq R2 Limit the amplitude.

[0171] And, exemplarily, the front axle torque limit range and the rear axle torque limit range can be expressed by the following formula (10).

[0172]

[0173] Among them, p tF is the reduction ratio from the front axle motor to the front wheel, p tR is the reduction ratio from the rear axle motor to the rear wheel, and R is the radius of the front and rear wheels.

[0174] After limiting the amplitudes of the first required torque and the second required torque respectively, the vehicle can control the front axle motor to output the final first required torque, and control the rear axle motor to output the final second required torque.

[0175] This method of limiting the amplitude of the first required torque and the second required torque can ensure the steering performance of the vehicle as much as possible while reducing the excessive variation in the amplitude of the torque output by the front and rear axle motors, thereby ensuring the stability of the vehicle's driving.

[0176] In some other embodiments, the vehicle may also output a first required torque Tq of the front axle motor. F2 and the second required torque Tq output by the rear axle motor R2 Gradient processing, filtering processing, etc. can be performed to achieve the purpose of limiting the amplitude of the first required torque and the second required torque, thereby ensuring the smoothness of the output torque of the front and rear axle motors and improving the stability and controllability of the vehicle.

[0177] In some schemes, multiple embodiments of the present application can be combined, and the combined scheme can be implemented. Optionally, some operations in the process of each method embodiment are optionally combined, and / or the order of some operations is optionally changed. In addition, the execution order between the steps of each process is only exemplary and does not constitute a restriction on the execution order between the steps. There can also be other execution orders between the steps. It is not intended to show that the execution order is the only order in which these operations can be performed. A person of ordinary skill in the art will think of a variety of ways to reorder the operations described in the embodiments of the present application. In addition, it should be noted that the process details involved in a certain embodiment of the present application are also applicable to other embodiments in a similar manner, or different embodiments can be used in combination.

[0178] In addition, some steps in the method embodiment may be equivalently replaced by other possible steps. Alternatively, some steps in the method embodiment may be optional and may be deleted in certain usage scenarios. Alternatively, other possible steps may be added to the method embodiment.

[0179] Furthermore, the various method embodiments may be implemented separately or in combination.

[0180] It is understandable that in order to achieve the above functions, the aforementioned vehicle includes hardware and / or software modules corresponding to the execution of each function. In combination with the algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application in combination with the embodiments, but such implementation should not be considered to be beyond the scope of this application.

[0181] In this embodiment, the functional modules of the vehicle can be divided according to the above method example. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware. It should be noted that the division of modules in this embodiment is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0182] The present application also provides an electronic device, such as Figure 7 As shown, the electronic device may include one or more processors 701 , a memory 702 and a communication interface 703 .

[0183] The memory 702 and the communication interface 703 are coupled to the processor 701. For example, the memory 702, the communication interface 703 and the processor 701 may be coupled together via a bus 704.

[0184] The communication interface 703 is used for data transmission with other devices. The memory 702 stores computer program codes. The computer program codes include computer instructions. When the computer instructions are executed by the processor 701, the electronic device executes the torque control method in the embodiment of the present application.

[0185] Among them, the processor 701 can be a processor or a controller, for example, a central processing unit (CPU), a general processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It can implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the present disclosure. The processor can also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, and the like.

[0186] The bus 704 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus 704 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 7 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0187] The present application also provides a torque control system, which may include a processor, and an inertial sensor, a steering wheel, an accelerator pedal, a brake pedal, a front axle motor, and a rear axle motor respectively connected to the processor. Figure 2 The functions of the torque controller, inertial sensor, steering wheel, accelerator pedal, brake pedal, front axle motor and rear axle motor can be referred to the contents of the aforementioned embodiments and will not be repeated here.

[0188] Exemplarily, an inertial sensor is used to obtain the yaw acceleration and lateral acceleration of the vehicle and send the yaw acceleration and lateral acceleration to a processor, a processor is used to obtain steering wheel angle information, accelerator pedal pedal travel information and brake pedal pedal travel information, and the processor is also used to determine the original front axle distributed torque and the rear axle distributed torque of the vehicle according to the accelerator pedal travel information or the brake pedal travel information in response to the steering angle information; and, according to the yaw acceleration and lateral acceleration, determine the compensated vehicle demand torque, the first torque after compensating the original front axle distributed torque and the second torque after compensating the original rear axle distributed torque; determine the transfer torque according to the lateral acceleration and the compensated vehicle demand torque; the transfer torque represents the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle; determine the first required torque of the front axle of the vehicle according to the transfer torque and the first torque, and determine the second required torque of the rear axle of the vehicle according to the transfer torque and the second torque; wherein the transfer torque is used to intervene in the first torque and the second torque, respectively.

[0189] In some possible application scenarios, the torque control system may further include a function switch. The function of the function switch may refer to the contents of the aforementioned embodiments and will not be described in detail here.

[0190] The present application also provides a torque control device, see Figure 8 As shown, the device includes an information acquisition unit 801 , a torque compensation unit 802 , a torque transfer unit 803 and a processing unit 804 .

[0191] The information acquisition unit 801 is used to acquire the yaw angular acceleration, lateral acceleration, front axle original distributed torque and rear axle original distributed torque of the vehicle.

[0192] The torque compensation unit 802 is used to determine the compensated vehicle required torque, the first torque after compensating the original distributed torque of the front axle, and the second torque after compensating the original distributed torque of the rear axle according to the yaw angular acceleration and the lateral acceleration.

[0193] The torque transfer unit 803 is used to determine the transfer torque according to the lateral acceleration and the required torque of the whole vehicle after compensation; wherein the transfer torque represents the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle.

[0194] The processing unit 804 is used to determine a first required torque of the front axle of the vehicle according to the transfer torque and the first torque, and to determine a second required torque of the rear axle of the vehicle according to the transfer torque and the second torque; the transfer torque is used to intervene in the first torque and the second torque respectively.

[0195] In some embodiments, the torque transfer unit 803 is also used to determine the lateral jerk of the vehicle based on the lateral acceleration; determine the torque transfer rate based on the lateral jerk; and determine the transfer torque based on the torque transfer rate and the compensated vehicle required torque.

[0196] In some embodiments, the torque compensation unit 802 is also used to determine the compensation torque distribution rate according to the yaw angular acceleration; determine the front axle compensation torque and the rear axle compensation torque of the vehicle according to the compensation torque distribution rate and the whole vehicle compensation torque, respectively; determine the first torque of the front axle according to the front axle compensation torque and the original distributed torque of the front axle, and determine the second torque to compensate the rear axle according to the rear axle compensation torque and the original distributed torque of the rear axle; the front axle compensation torque is used to compensate the original distributed torque of the front axle, and the rear axle compensation torque is used to compensate the original distributed torque of the rear axle.

[0197] In some embodiments, the torque compensation unit 802 is also used to determine the vehicle's whole vehicle compensation torque based on the yaw angular acceleration and the lateral acceleration; determine the vehicle's compensated whole vehicle required torque based on the whole vehicle compensation torque and the requested torque; and the whole vehicle compensation torque is used to compensate for the requested torque.

[0198] In some embodiments, the processing unit 804 is also used to obtain the current working state of the vehicle; the working state is related to the yaw angular acceleration and the lateral jerk; the lateral jerk is used to characterize the rate of change of the lateral acceleration; according to the working state, the torque control strategy is determined; based on the torque control strategy, the first required torque of the front axle of the vehicle is determined according to the transfer torque and the first torque, and the second required torque of the rear axle of the vehicle is determined according to the transfer torque and the second torque.

[0199] In some embodiments, the information acquisition unit 801 includes an inertial sensor; the inertial sensor is used to acquire the yaw angular acceleration and lateral acceleration of the vehicle.

[0200] The functions that can be implemented by the above-mentioned information acquisition unit 801, torque compensation unit 802, torque transfer unit 803 and processing unit 804 are only examples. In some other embodiments, the information acquisition unit 801, torque compensation unit 802, torque transfer unit 803 and processing unit 804 can also respectively implement other related steps as described in the above-mentioned embodiments.

[0201] An embodiment of the present application also provides a chip, a memory, and one or more processors; the memory is coupled to the processor; wherein the memory stores computer program code, and the computer program code includes computer instructions, and when the computer instructions are executed by the processor, the chip executes the relevant method steps in the above method embodiment.

[0202] An embodiment of the present application also provides a vehicle, which includes the torque control device in the above embodiment, or includes the chip in the above embodiment.

[0203] An embodiment of the present application also provides a computer-readable storage medium, which includes computer instructions. When the computer instructions are in a chip, the chip executes the relevant method steps in the above method embodiment.

[0204] The embodiment of the present application also provides a computer program product. When the computer program product is run on a computer, it enables the computer to execute the relevant method steps in the above method embodiment.

[0205] Among them, the vehicle, torque control device, electronic device, computer storage medium or computer program product provided in the present application are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding methods provided above and will not be repeated here.

[0206] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0207] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0208] The units described as separate components may or may not be physically separated, and the components shown as units may be one physical unit or multiple physical units, that is, they may be located in one place or distributed in multiple different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0209] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0210] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium, including several instructions to enable a device (which can be a single-chip microcomputer, chip, etc.) or a processor (processor) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read only memory (ROM), random access memory (RAM), disk or optical disk and other media that can store program code.

[0211] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application shall be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A torque control method, characterized in that: The method comprises: Obtaining the yaw angular acceleration, lateral acceleration, front axle original distributed torque, and rear axle original distributed torque of the vehicle; According to the yaw acceleration and the lateral acceleration, a compensated vehicle demand torque, a first torque after compensating the original distributed torque of the front axle, and a second torque after compensating the original distributed torque of the rear axle are determined; the compensated vehicle demand torque is a torque after compensating the requested torque with the vehicle compensation torque, the vehicle compensation torque is determined according to the yaw acceleration and the lateral acceleration, and the requested torque is determined according to the pedal stroke information of the vehicle; the first torque is determined according to the front axle compensation torque and the original distributed torque of the front axle, the second torque is determined according to the rear axle compensation torque and the original distributed torque of the rear axle, the front axle compensation torque and the rear axle compensation torque are both determined according to the vehicle compensation torque and the compensation torque distribution rate determined by the yaw acceleration; the front axle compensation torque is used to compensate the original distributed torque of the front axle, and the rear axle compensation torque is used to compensate the original distributed torque of the rear axle; Determine a transfer torque according to the lateral acceleration and the compensated vehicle required torque; the transfer torque represents a torque transferred from a front axle of the vehicle to a rear axle of the vehicle or a torque transferred from a rear axle of the vehicle to a front axle of the vehicle; the transfer torque is determined according to a torque transfer rate and the compensated vehicle required torque, and the torque transfer rate is determined according to a lateral jerk of the vehicle determined by the lateral acceleration; A first required torque of a front axle of the vehicle is determined based on the transfer torque and the first torque, and a second required torque of a rear axle of the vehicle is determined based on the transfer torque and the second torque; the transfer torque is used to intervene in the first torque and the second torque respectively.

2. The method according to claim 1, characterized in that The method of determining a first required torque of a front axle of a vehicle according to the transfer torque and the first torque, and determining a second required torque of a rear axle of a vehicle according to the transfer torque and the second torque, comprises: Acquiring a current working state of the vehicle; the working state is related to the yaw angular acceleration and the lateral jerk; the lateral jerk is used to characterize the rate of change of the lateral acceleration; Determining a torque control strategy according to the working state; Based on the torque control strategy, a first required torque of the front axle of the vehicle is determined according to the transfer torque and the first torque, and a second required torque of the rear axle of the vehicle is determined according to the transfer torque and the second torque.

3. The method according to claim 2, characterized in that The working state includes a steady state and an unstable state; when the values ​​of the yaw angular acceleration and the lateral jerk include positive values ​​or negative values, the working state is a steady state; when the values ​​of the yaw angular acceleration and the lateral jerk include positive values ​​and negative values, the working state is an unstable state.

4. The method according to claim 3, characterized in that: Determining the torque control strategy according to the working state includes: When the working state is steady state, If the value of the yaw acceleration and the value of the lateral jerk are both positive values, it is determined that the torque control strategy is that the transfer torque is transferred from the front axle to the rear axle, and if the type of the requested torque is driving torque, the compensation method for the requested torque is torque reduction, and if the type of the requested torque is recovery torque, the compensation method for the requested torque is torque increase; the type of the requested torque is determined according to the state of the accelerator pedal or the brake pedal of the vehicle; If the value of the yaw angular acceleration and the value of the lateral jerk are both negative values, it is determined that the torque control strategy is that the transfer torque is transferred from the rear axle to the front axle, and, if the type of the requested torque is driving torque, the compensation method for the requested torque is torque increase, and if the type of the requested torque is recovery torque, the compensation method for the requested torque is torque reduction.

5. The method according to claim 3, characterized in that: Determining the torque control strategy according to the working state includes: When the working state is an unstable state, If the value of the yaw acceleration is a negative value and the value of the lateral jerk is a positive value, determining that the torque control strategy is that the transfer torque is transferred from the front axle to the rear axle, and the compensation method for the requested torque is torque reduction; If the value of the yaw acceleration is a positive value and the value of the lateral jerk is a negative value, it is determined that the torque control strategy is to transfer the transfer torque from the rear axle to the front axle, and the compensation method for the requested torque is torque reduction.

6. The method according to claim 2, characterized in that The method of determining a first required torque of a front axle of a vehicle according to the transfer torque and the first torque based on the torque control strategy, and determining a second required torque of a rear axle of the vehicle according to the transfer torque and the second torque, comprises: When the torque control strategy is that the transfer torque is distributed from the front axle to the rear axle, the transfer torque is reduced on the first torque to obtain a first required torque, and the transfer torque is superimposed on the second torque to obtain a second required torque; or When the torque control strategy is that the transfer torque is distributed from the rear axle to the front axle, the transfer torque is superimposed on the first torque to obtain a first required torque, and the transfer torque is reduced on the second torque to obtain a second required torque.

7. The method according to claim 1, characterized in that The method further comprises: Obtaining the front axle load and the rear axle load of the vehicle; Determining a front axle torque limit range of the vehicle according to the lateral acceleration and the front axle load, and determining a rear axle torque limit range of the vehicle according to the lateral acceleration and the rear axle load; the front axle torque limit range is used to limit the amplitude of the first required torque, and the rear axle torque limit range is used to limit the amplitude of the second required torque; The method further comprises: The front axle motor is controlled to output a final first required torque after the first required torque is limited in amplitude, and the rear axle motor is controlled to output a final second required torque after the second required torque is limited in amplitude.

8. The method according to claim 1, characterized in that: Obtain the original distributed torque of the front axle and the original distributed torque of the rear axle, including: Acquiring current pedal travel information and current vehicle speed information of the vehicle; the pedal travel information is used to indicate the distance moved when the brake pedal is pressed or the distance moved when the accelerator pedal is pressed; determining a requested torque of the vehicle according to the pedal travel information; acquiring a torque original distribution rate corresponding to the requested torque and the vehicle speed information; The front axle original distributed torque and the rear axle original distributed torque are determined according to the request torque and the torque original distributed rate.

9. A torque control device, characterized in that: include: An information acquisition unit, used for acquiring the yaw angular acceleration, lateral acceleration, original distributed torque of the front axle and original distributed torque of the rear axle of the vehicle; a torque compensation unit, configured to determine, according to the yaw angular acceleration and the lateral acceleration, a compensated vehicle required torque, a first torque compensated for the original distributed torque of the front axle, and a second torque compensated for the original distributed torque of the rear axle; The compensated vehicle demand torque is a torque obtained by compensating the request torque with the vehicle compensation torque, the vehicle compensation torque is determined according to the yaw acceleration and the lateral acceleration, and the request torque is determined according to the pedal stroke information of the vehicle; The first torque is determined according to the front axle compensation torque and the front axle original distribution torque, the second torque is determined according to the rear axle compensation torque and the rear axle original distribution torque, and both the front axle compensation torque and the rear axle compensation torque are determined according to the whole vehicle compensation torque and the compensation torque distribution rate determined by the yaw angular acceleration; The front axle compensation torque is used to compensate the front axle original distribution torque, and the rear axle compensation torque is used to compensate the rear axle original distribution torque; a torque transfer unit, configured to determine a transfer torque according to the lateral acceleration and the compensated vehicle required torque; the transfer torque represents a torque transferred from a front axle of the vehicle to a rear axle of the vehicle or a torque transferred from a rear axle of the vehicle to a front axle of the vehicle; the transfer torque is determined according to a torque transfer rate and the compensated vehicle required torque, the torque transfer rate being determined according to a lateral jerk of the vehicle determined by the lateral acceleration; A processing unit is used to determine a first required torque of a front axle of the vehicle based on the transfer torque and the first torque, and to determine a second required torque of a rear axle of the vehicle based on the transfer torque and the second torque; the transfer torque is used to intervene in the first torque and the second torque respectively.

10. The device according to claim 9, characterized in that The processing unit is further used to obtain the current working state of the vehicle; the working state is related to the yaw angular acceleration and the lateral jerk; the lateral jerk is used to characterize the rate of change of the lateral acceleration; and determine the torque control strategy according to the working state; Based on the torque control strategy, a first required torque of the front axle of the vehicle is determined according to the transfer torque and the first torque, and a second required torque of the rear axle of the vehicle is determined according to the transfer torque and the second torque.

11. The device according to claim 9, characterized in that The information acquisition unit includes an inertial sensor; the inertial sensor is used to acquire the yaw angular acceleration and the lateral acceleration of the vehicle.

12. A torque control system, characterized in that: The vehicle comprises a processor, and an inertial sensor, a steering wheel, an accelerator pedal, a brake pedal, a front axle motor and a rear axle motor respectively connected to the processor; the inertial sensor is used to obtain the yaw angular acceleration and the lateral acceleration of the vehicle, and send the yaw angular acceleration and the lateral acceleration to the processor; The processor is used to obtain the steering wheel angle information, the pedal stroke information of the accelerator pedal and the pedal stroke information of the brake pedal; The processor is further configured to determine a front axle original distributed torque and a rear axle original distributed torque of the vehicle according to pedal travel information of the accelerator pedal or pedal travel information of the brake pedal in response to the rotation angle information; and, determining, according to the yaw angular acceleration and the lateral acceleration, a compensated vehicle demand torque, a first torque compensated for the original distributed torque of the front axle, and a second torque compensated for the original distributed torque of the rear axle; The compensated vehicle demand torque is a torque obtained by compensating the request torque with the vehicle compensation torque, the vehicle compensation torque is determined according to the yaw acceleration and the lateral acceleration, and the request torque is determined according to the pedal stroke information of the vehicle; The first torque is determined according to the front axle compensation torque and the original front axle distribution torque, the second torque is determined according to the rear axle compensation torque and the original rear axle distribution torque, the front axle compensation torque and the rear axle compensation torque are both determined according to the vehicle compensation torque and the compensation torque distribution rate determined by the yaw angular acceleration; the front axle compensation torque is used to compensate the front axle original distribution torque, and the rear axle compensation torque is used to compensate the rear axle original distribution torque. The transfer torque is determined according to the lateral acceleration and the compensated vehicle required torque; the transfer torque represents the torque transferred from the front axle of the vehicle to the rear axle of the vehicle or the torque transferred from the rear axle of the vehicle to the front axle of the vehicle; the transfer torque is determined according to the torque transfer rate and the compensated vehicle required torque, and the torque transfer rate is determined according to the lateral jerk of the vehicle determined by the lateral acceleration; the first required torque of the front axle of the vehicle is determined according to the transfer torque and the first torque, and the second required torque of the rear axle of the vehicle is determined according to the transfer torque and the second torque; the transfer torque is used to intervene in the first torque and the second torque respectively.

13. A chip, characterized in that: It comprises a memory and one or more processors; the memory is coupled to the processor; wherein the memory stores computer program code, the computer program code comprises computer instructions, and when the computer instructions are executed by the processor, the chip executes the torque control method as described in any one of claims 1-8.

14. A vehicle, characterized in that: The vehicle comprises the torque control device as described in any one of claims 9 to 11, or comprises the chip as described in claim 13.

15. A computer-readable storage medium, characterized in that: The invention comprises computer instructions, and when the computer instructions are executed on a chip, the chip executes the torque control method as claimed in any one of claims 1 to 8.

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