Electric four-wheel drive vehicle motor torque control method and device

Abstract

This application relates to the field of electric drive system technology for electric vehicles, and particularly to a method and apparatus for controlling motor torque in an electric four-wheel drive vehicle. The method includes: when the electric drive differential of any axle enters an active protection mode, acquiring the difference between the actual torque of that axle and the currently required torque; superimposing the difference with an initial torque requirement value to obtain the final required torque for the remaining axles (excluding the first axle); and controlling the motors of the remaining axles to output torque according to the final required torque when the electric drive differential of any axle enters an active protection mode. This application's embodiment can acquire the final required torque for the remaining axles when the electric drive differential of any axle enters an active protection mode, and control the motors of the remaining axles to output torque according to the final required torque when the motor differentials of the remaining axles do not enter an active protection mode, thereby ensuring that the electric drive output torque meets the driver's torque requirements, thus improving the user's driving experience and enhancing vehicle safety.

Description

Technical Field

[0001] This application relates to the field of electric vehicle electric drive system technology, and in particular to a method and device for controlling the motor torque of an electric four-wheel drive vehicle. Background Technology

[0002] In related technologies, control is achieved by designing an active protection function for the electric drive differential. When an excessive speed difference between the left and right wheels is detected, the motor output torque is limited to a safe range through the differential protection control of the electric drive system itself.

[0003] However, in related technologies, such as patent CN115143259A "Differential Protection Control Method, Device and Electronic Equipment", the excessive speed difference between the left and right wheels causes the active protection function of the electric drive differential to limit the output torque of the motor. As a result, the output torque of the electric drive cannot meet the driver's torque requirements, which reduces the user's driving experience and reduces the safety and reliability of the vehicle. This issue urgently needs to be addressed. Summary of the Invention

[0004] This application provides a method and device for controlling the motor torque of an electric four-wheel drive vehicle, in order to solve the problems in the related technology where the active protection function of the electric drive differential limits the motor output torque due to the excessive speed difference between the left and right wheels, resulting in the electric drive output torque failing to meet the driver's torque requirements, reducing the user's driving experience, and reducing the safety and reliability of the vehicle.

[0005] The first aspect of this application provides a motor torque control method for an electric four-wheel drive vehicle, comprising the following steps: when the electric drive differential of any axle enters an active protection mode, obtaining the difference between the actual torque of the any axle and the current required torque; superimposing the difference with the initial torque requirement value to obtain the final required torque for the remaining axles other than the any axle; when the motor differentials of the remaining axles do not enter the active protection mode, controlling the motors of the remaining axles to output torque according to the final required torque.

[0006] Based on the above technical means, the embodiments of this application can obtain the final required torque of the other shafts when the electric drive differential of any shaft enters the active protection mode, and control the motors of the other shafts to output torque according to the final required torque when the motor differentials of the other shafts do not enter the active protection mode, so that the electric drive output torque meets the torque required by the driver, thereby improving the user's driving experience and improving the safety of the vehicle.

[0007] Optionally, in one embodiment of this application, the method further includes: when the motor differential of the other shaft enters the active protection mode, determining whether the maximum allowable torque under the current wheel speed difference of the other shaft is greater than the final required torque; if the maximum allowable torque is greater than the final required torque, controlling the motor of the other shaft to output torque based on the maximum allowable torque, otherwise outputting torque according to the final required torque.

[0008] Based on the above technical means, the embodiments of this application can control the motors of the other shafts to output torque based on the maximum allowable torque when the maximum allowable torque under the current wheel speed difference of the other shafts is greater than the final required torque, thereby improving the reliability of motor torque control.

[0009] Optionally, in one embodiment of this application, after controlling the remaining shafts to output torque based on the final allowable torque, the method further includes: determining the maximum allowable torque of each shaft based on the current wheel speed difference of each shaft after every preset time interval, so as to control the motor of each shaft to output torque based on the maximum allowable torque.

[0010] Based on the above-mentioned technical means, the embodiments of this application can determine the maximum allowable torque of each axle according to the current wheel speed difference of each axle at regular intervals, thereby reducing the risk of differential failure.

[0011] Optionally, in one embodiment of this application, the method further includes: receiving a user's differential lock command; and controlling the vehicle to enter a differential lock state based on the differential lock command, so as to distribute all the motor output torque of each axle to the wheel end torque output on the side with a higher coefficient of adhesion.

[0012] Based on the above-mentioned technical means, the embodiments of this application can control the vehicle to enter the differential lock state, and distribute all the motor output torque of each axle to the wheel end torque output on the side with a higher coefficient of adhesion, thereby improving the safety and stability of the vehicle and meeting the user's vehicle usage needs.

[0013] Optionally, in one embodiment of this application, the method further includes: when the electric drive differential of any shaft does not enter the active protection mode, controlling the motor of any shaft to output torque based on the current required torque.

[0014] Based on the above-mentioned technical means, the embodiments of this application can control the motor of any shaft to output torque based on the current required torque to achieve differential protection, reduce the risk of differential failure, and improve the safety and reliability of the vehicle.

[0015] A second aspect of this application provides a motor torque control device for an electric four-wheel drive vehicle, comprising: an acquisition module, configured to acquire the difference between the actual torque and the current required torque of any axle when the electric drive differential of any axle enters an active protection mode; an overlay module, configured to overlay the difference and an initial torque requirement value to obtain the final required torque of the remaining axles other than the aforementioned axle; and a control module, configured to control the motors of the remaining axles to output torque according to the final required torque when the motor differentials of the remaining axles do not enter the active protection mode.

[0016] Optionally, in one embodiment of this application, the apparatus further includes: a judgment module, configured to determine whether the maximum allowable torque under the current wheel speed difference of the remaining shaft is greater than the final required torque when the motor differential of the remaining shaft enters the active protection mode; and a processing module, configured to control the motor of the remaining shaft to output torque based on the maximum allowable torque if the maximum allowable torque is greater than the final required torque, otherwise output torque based on the final required torque.

[0017] Optionally, in one embodiment of this application, the apparatus of this application embodiment further includes: a determining module, configured to, after controlling the remaining shafts to output torque based on the final allowable torque, determine the maximum allowable torque of each shaft based on the current wheel speed difference of each shaft after every preset time interval, so as to control the motor of each shaft to output torque based on the maximum allowable torque.

[0018] Optionally, in one embodiment of this application, the apparatus further includes: a receiving module for receiving a user's differential lock command; and a control module for controlling the vehicle to enter a differential lock state based on the differential lock command, so as to distribute all the motor output torque of each axle to the wheel end torque output on the side with a higher coefficient of adhesion.

[0019] Optionally, in one embodiment of this application, the apparatus of this application embodiment further includes: a control module, configured to control the motor of the any shaft to output torque based on the current required torque when the electric drive differential of the any shaft has not entered the active protection mode.

[0020] A third aspect of this application provides a vehicle, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the motor torque control method for an electric four-wheel drive vehicle as described in the above embodiments.

[0021] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for controlling the motor torque of an electric four-wheel drive vehicle.

[0022] The beneficial effects of this application are:

[0023] (1) In this embodiment of the application, when the maximum allowable torque under the current wheel speed difference of the other shafts is greater than the final required torque, the motors of the other shafts can be controlled to output torque based on the maximum allowable torque, thereby improving the reliability of motor torque control.

[0024] (2) The embodiments of this application can control the vehicle to enter the differential lock state, and distribute all the motor output torque of each axle to the wheel end torque output on the side with higher adhesion coefficient, thereby improving the safety and stability of the vehicle and meeting the user's vehicle use needs.

[0025] (3) In this embodiment, when the electric drive differential of any axle enters the active protection mode, the final required torque of the other axles can be obtained, and when the motor differential of the other axles does not enter the active protection mode, the motors of the other axles can be controlled to output torque according to the final required torque, so that the electric drive output torque meets the driver's required torque, thereby improving the user's driving experience and improving the vehicle's safety.

[0026] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0027] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0028] Figure 1 This is a flowchart of a motor torque control method for an electric four-wheel drive vehicle according to an embodiment of this application;

[0029] Figure 2 A flowchart of a motor torque control method for an electric four-wheel drive vehicle according to a specific embodiment of this application;

[0030] Figure 3 This is a schematic diagram of the structure of the motor torque control device for an electric four-wheel drive vehicle according to an embodiment of this application;

[0031] Figure 4 This is a structural schematic diagram of the vehicle provided in this application.

[0032] Among them, 10-motor torque control device for electric four-wheel drive vehicles; 100-acquisition module, 200-overlay module and 300-control module; 401-memory, 402-processor and 403-communication interface. Detailed Implementation

[0033] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0034] The following description, with reference to the accompanying drawings, illustrates a method and apparatus for controlling the motor torque of an electric four-wheel drive vehicle according to embodiments of this application. Addressing the problem mentioned in the background section of the related art where excessive speed difference between the left and right wheels leads to the electric drive differential's active protection function limiting the motor output torque, resulting in the electric drive output torque failing to meet the driver's torque requirements, thus reducing the user's driving experience and lowering vehicle safety and reliability, this application provides a method for controlling the motor torque of an electric four-wheel drive vehicle. In this method, when the electric drive differential of any axle enters active protection mode, the difference between the actual torque of that axle and the current required torque is obtained. This difference is then superimposed with the initial torque requirement value to obtain the final required torque for the remaining axles (excluding that axle). When the motor differentials of the remaining axles are not in active protection mode, the motors of the remaining axles are controlled to output torque according to the final required torque, effectively meeting the driver's torque requirements, thereby improving the user's driving experience and enhancing vehicle safety. This solves the problem in related technologies where excessive speed difference between the left and right wheels causes the active protection function of the electric drive differential to limit the motor output torque, resulting in the electric drive output torque failing to meet the driver's torque requirements, reducing the user's driving experience, and lowering the vehicle's safety and reliability.

[0035] Specifically, Figure 1 This is a schematic flowchart illustrating a motor torque control method for an electric four-wheel drive vehicle provided in an embodiment of this application.

[0036] like Figure 1 As shown, the motor torque control method for this electric four-wheel drive vehicle includes the following steps:

[0037] In step S101, when the electric drive differential of any shaft enters the active protection mode, the difference between the actual torque of any shaft and the current required torque is obtained.

[0038] It is understood that, in the embodiments of this application, when the electric drive differential of any axis enters the active protection mode, for example, when the electric drive system controller detects that the speed difference between the left and right wheels is higher than a certain speed difference threshold, the electric drive system controller of any axis enters the differential active protection mode and obtains the difference between the actual torque of any axis and the current required torque, thereby improving the executability of motor torque control.

[0039] For example, when one wheel of an electric four-wheel drive vehicle is on a normal road surface with a high coefficient of friction and the other wheel is on an icy road surface with a low coefficient of friction, the speed of the wheel on the icy road surface will increase sharply, the speed difference between the wheel and the normal road surface will increase, and the wheel speed will increase sharply, causing the differential planetary gears to rotate at high speed around the planetary shaft.

[0040] Next, in any of the embodiments of this application, the electric drive system controller of any axle can receive the wheel speed difference signal and determine whether to enter the differential active protection mode. When the wheel speed difference is detected to be higher than a certain speed difference threshold, the electric drive system controller of any axle enters the differential active protection mode. When entering the differential active protection mode, the electric drive differential active protection function will limit the motor torque output to no more than the maximum allowable torque of the differential according to the wheel speed difference at this time, so as to avoid the electric drive differential from burning out due to excessive left and right wheel speed difference.

[0041] Secondly, to avoid vehicle impact caused by excessively rapid torque change rates, the motor controller can determine the optimal torque change rate based on the current acceleration and control the motor torque to vary with different wheel speed differences. The optimal torque change rate corresponding to different vehicle accelerations is obtained through calibration, and the calibration results are then stored in the controller in the form of a data table. Table 1 is a data table of the optimal torque change rate corresponding to different vehicle accelerations, as detailed in Table 1 below:

[0042] Table 1

[0043] Vehicle acceleration <![CDATA[a1]]> <![CDATA[a2]]> <![CDATA[a3]]> <![CDATA[a4]]> <![CDATA[a5]]> ... Optimal Torque Variation Rate <![CDATA[ΔT1]]> <![CDATA[ΔT2]]> <![CDATA[ΔT3]]> <![CDATA[ΔT4]]> <![CDATA[ΔT5]]> ...

[0044] In addition, the maximum allowable torque of the differential under different wheel speed differences can be obtained through differential testing or simulation and pre-stored in the motor controller. Table 2 shows the maximum allowable torque data under different wheel speed differences, as detailed in Table 2 below:

[0045] Wheel speed difference V1 V2 V3 V4 V5 ... Maximum allowable torque T1 T2 T3 T4 T5 ...

[0046] Finally, since the actual output torque of any one-axis motor is limited and cannot meet the torque requirements of the whole vehicle, the embodiments of this application can calculate the difference between the actual output torque under the corresponding speed difference and the required torque sent by the whole vehicle controller according to the controller of any one-axis motor, and send the torque difference to the whole vehicle controller, thereby improving the feasibility of motor torque control and improving the safety and reliability of the vehicle.

[0047] It should be noted that the speed difference threshold is set by those skilled in the art based on the actual situation, and no specific limitation is made here.

[0048] In step S102, the final required torque for the remaining shafts (excluding any one shaft) is obtained by superimposing the difference and the initial torque requirement value.

[0049] It is understood that the embodiments of this application can be based on the superposition of the difference and the initial torque requirement value. For example, the vehicle controller in the embodiments of this application can use the difference as compensation and superimpose it with the initial torque requirement value sent to the other axle motors to obtain the final required torque of the other axle motors, and send it to the other axle motor controller. The other axle motor controller can collect the speed difference between the left and right wheels of the other axles, thereby determining the maximum torque that can be output under the current wheel speed difference, and then increasing the torque output of the other axle motors to meet the torque requirements of the vehicle, reducing the risk of differential failure and improving vehicle safety.

[0050] In step S103, when the motor differentials of the other shafts have not entered the active protection mode, the motors of the other shafts are controlled to output torque according to the final required torque.

[0051] It is understood that, in the embodiments of this application, when the differential of the motors on the other axles has not entered the active protection mode, for example, the motor controller of the other axles collects the speed difference between the left and right wheels of the other axles in real time, and determines whether to enter the active protection mode of the differential based on the speed difference between the left and right wheels. When the torque demand value is less than the maximum torque allowed to be output under the current wheel speed difference, the motor controller of the other axles controls the motor to output a torque equal to the torque demand value, so that the torque generated by any axle motor and the other axle motors still meets the torque demand of the whole vehicle, thereby effectively improving the stability of the vehicle and improving the user's driving experience.

[0052] Optionally, in one embodiment of this application, the method further includes: when the motor differential of the other shafts enters the active protection mode, determining whether the maximum allowable torque under the current wheel speed difference of the other shafts is greater than the final required torque; if the maximum allowable torque is greater than the final required torque, controlling the motors of the other shafts to output torque based on the maximum allowable torque, otherwise outputting torque based on the final required torque.

[0053] For example, the controller of the other axle motors collects the speed difference between the left and right wheels of the other axle in real time. Based on the speed difference, it determines whether to enter the differential active protection mode. When the speed difference between the left and right wheels is greater than a threshold, the motor differential of the other axle enters the active protection mode. It looks up a table to determine the maximum allowable output torque under the current wheel speed difference. It compares the maximum allowable output torque under the current left and right wheel speed difference with the final required torque signal of the other axle motor received from the vehicle controller. When the torque requirement value is greater than the maximum allowable output torque under the current wheel speed difference, the actual output torque of the other axle electric drive control is the maximum allowable output torque under the current wheel speed difference. Otherwise, it outputs torque according to the final required torque, thereby improving the reliability of motor torque control.

[0054] It should be noted that the threshold is set by those skilled in the art based on the actual situation, and no specific limitation is made here.

[0055] Optionally, in one embodiment of this application, after controlling the other shafts to output torque based on the final allowable torque, the method further includes: determining the maximum allowable torque of each shaft based on the current wheel speed difference of each shaft after every preset time interval, so as to control the motor of each shaft to output torque based on the maximum allowable torque.

[0056] For example, since any one axis motor and the other axis motors enter the differential active protection mode, the motor controller can re-determine the maximum allowable output torque at regular intervals based on the speed difference between the left and right wheels of each axis by consulting Table 2 in the above steps. This controls the torque of each axis motor to change at the optimal rate and output the maximum torque, thereby reducing the risk of differential failure.

[0057] It should be noted that the preset duration is set by those skilled in the art based on the actual situation, and no specific limitation is made here.

[0058] Optionally, in one embodiment of this application, the method further includes: receiving a user's differential lock command; controlling the vehicle to enter a differential lock state based on the differential lock command, so as to distribute all the motor output torque of each axle to the wheel end torque output of the side with a higher coefficient of adhesion.

[0059] In actual implementation, this application embodiment can receive differential lock commands from users. For example, when the required torque of the whole vehicle is greater than the sum of the output torque of any axle and the motors of the other axles, the user can initiate a differential lock command through a physical button in the vehicle. This application embodiment can control the vehicle to lock the output shaft on the side with higher speed based on the differential lock command, and distribute all the output torque of the motors on each axle to the torque output of the wheel end on the side with higher adhesion coefficient. The driver can continue to increase the opening of the accelerator pedal to increase the torque demand of the whole vehicle, thereby improving the safety and stability of the vehicle and meeting the user's vehicle use needs.

[0060] Optionally, in one embodiment of this application, the method further includes: when the electric drive differential of any axis does not enter the active protection mode, controlling the motor of any axis to output torque based on the current required torque.

[0061] In actual operation, when the electric drive differential of any axle does not enter the active protection mode, it is recognized that the wheel speed difference is not higher than a certain speed difference threshold. In this embodiment, the motor of any axle can be controlled to output torque based on the current required torque to achieve differential protection, reduce the risk of differential failure, and improve the safety and reliability of the vehicle.

[0062] For example, such as Figure 2 As shown, the working principle of the embodiments of this application will be described in detail below with a specific example.

[0063] Step S201: The first shaft motor receives the speed difference signal between the left and right wheels.

[0064] Step S202: The first axis motor controller determines whether to enter the differential active protection mode. If it enters the differential active protection mode, then execute step S204; otherwise, execute step S203.

[0065] Step S203: The first shaft motor outputs the actual torque at the required torque value.

[0066] Step S204: Limit the actual rate of change of the motor to no more than the maximum allowable torque under the current wheel speed difference.

[0067] Step S205: Calculate the difference between the actual and required torque and send it to the vehicle controller.

[0068] Step S206: The vehicle controller adds the difference to the initial torque requirement value of the second shaft motor to obtain the final required torque and sends it to the second shaft motor.

[0069] Step S207: The second axis motor controller determines whether to enter the differential active protection mode. If it enters the differential active protection mode, then execute step S208; otherwise, execute step S209.

[0070] Step S208: Determine whether the maximum allowable torque under the current left and right wheel speed difference is greater than the final required torque. If it is greater than the final required torque, proceed to step S210; otherwise, proceed to step S209.

[0071] Step S209: The second shaft motor outputs a torque equal to the torque requirement, and the combined torque of the two shaft motors meets the torque requirements of the entire vehicle.

[0072] Step S210: The second shaft motor outputs the maximum allowable torque under the current wheel speed difference.

[0073] Step S211: The two-axis motors re-determine the maximum allowable torque based on the speed difference between the left and right wheels after a certain period of time, and output the maximum allowable torque at the newly determined maximum allowable torque.

[0074] Step S212: Enter the differential lock state, and the motor output torque is fully distributed to the side with the higher coefficient of friction. The driver can continue to increase the torque demand of the whole vehicle and drive out of the icy road surface, which improves the safety and stability of the vehicle.

[0075] The motor torque control method for an electric four-wheel drive vehicle proposed in this application can obtain the difference between the actual torque and the current required torque of any axle when the electric drive differential of any axle enters the active protection mode. This difference is then superimposed with the initial torque requirement value to obtain the final required torque for the remaining axles. When the motor differentials of the remaining axles are not in the active protection mode, the motors of the remaining axles are controlled to output torque according to the final required torque. This ensures that the electric drive output torque effectively meets the driver's torque requirements, thereby improving the user's driving experience and enhancing vehicle safety. This solves the problems in related technologies where excessive speed differences between the left and right wheels cause the active protection function of the electric drive differential to limit the motor output torque, resulting in the electric drive output torque failing to meet the driver's torque requirements, reducing the user's driving experience, and lowering vehicle safety and reliability.

[0076] Next, referring to the accompanying drawings, a motor torque control device for an electric four-wheel drive vehicle according to an embodiment of this application is described.

[0077] Figure 3 This is a block diagram of the motor torque control device of an electric four-wheel drive vehicle according to an embodiment of this application.

[0078] like Figure 3 As shown, the motor torque control device 10 of the electric four-wheel drive vehicle includes: an acquisition module 100, an overlay module 200, and a control module 300.

[0079] Specifically, the acquisition module 100 is used to acquire the difference between the actual torque and the current required torque of any shaft when the electric drive differential of any shaft enters the active protection mode.

[0080] The superposition module 200 is used to superimpose the difference and the initial torque requirement value to obtain the final required torque of the remaining shafts except for any one shaft.

[0081] The control module 300 is used to control the motors of the other shafts to output torque according to the final required torque when the motor differentials of the other shafts have not entered the active protection mode.

[0082] Optionally, in one embodiment of this application, the apparatus 10 of this application embodiment further includes: a judgment module and a processing module.

[0083] The judgment module is used to determine whether the maximum allowable torque under the current wheel speed difference of the other shafts is greater than the final required torque when the motor differential of the other shafts enters the active protection mode.

[0084] The processing module is used to control the motors of the remaining axes to output torque based on the maximum allowable torque if the maximum allowable torque is greater than the final required torque; otherwise, it outputs torque based on the final required torque.

[0085] Optionally, in one embodiment of this application, the apparatus 10 of this application embodiment further includes: a determining module.

[0086] The determining module is used to determine the maximum allowable torque of each shaft based on the current wheel speed difference of each shaft after controlling the output torque of the other shafts based on the final allowable torque, at preset time intervals, so as to control the motor of each shaft to output torque based on the maximum allowable torque.

[0087] Optionally, in one embodiment of this application, the apparatus 10 of this embodiment further includes a receiving module and a control module.

[0088] The receiving module is used to receive the user's differential lock command.

[0089] The control module is used to control the vehicle to enter the differential lock state based on the differential lock command, so as to distribute all the motor output torque of each axle to the wheel end torque output of the side with higher adhesion coefficient.

[0090] Optionally, in one embodiment of this application, the apparatus 10 of this application embodiment further includes a control module.

[0091] The control module is used to control the motor of any axis to output torque based on the current torque demand when the electric drive differential of any axis has not entered the active protection mode.

[0092] It should be noted that the explanation of the above-described embodiment of the motor torque control method for electric four-wheel drive vehicles also applies to the motor torque control device for electric four-wheel drive vehicles in this embodiment, and will not be repeated here.

[0093] The electric motor torque control device for an electric four-wheel drive vehicle proposed in this application can, when the electric drive differential of any axle enters the active protection mode, obtain the difference between the actual torque of that axle and the current required torque, and then superimpose the difference with the initial torque requirement value to obtain the final required torque for the remaining axles. When the motor differentials of the remaining axles are not in the active protection mode, the device controls the motors of the remaining axles to output torque according to the final required torque, so that the electric drive output torque effectively meets the driver's torque requirement, thereby improving the user's driving experience and enhancing vehicle safety. This solves the problems in related technologies where excessive speed difference between the left and right wheels causes the active protection function of the electric drive differential to limit the motor output torque, resulting in the electric drive output torque failing to meet the driver's torque requirement, reducing the user's driving experience, and decreasing vehicle safety and reliability.

[0094] Figure 4 A schematic diagram of the structure of a vehicle provided in an embodiment of this application. The vehicle may include:

[0095] The memory 401, the processor 402, and the computer program stored on the memory 401 and capable of running on the processor 402.

[0096] When the processor 402 executes the program, it implements the motor torque control method for the electric four-wheel drive vehicle provided in the above embodiments.

[0097] Furthermore, the vehicle also includes:

[0098] Communication interface 403 is used for communication between memory 401 and processor 402.

[0099] The memory 401 is used to store computer programs that can run on the processor 402.

[0100] The memory 401 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0101] If the memory 401, processor 402, and communication interface 403 are implemented independently, then the communication interface 403, memory 401, and processor 402 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be divided into address buses, data buses, control buses, etc. For ease of representation, Figure 4 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0102] Optionally, in a specific implementation, if the memory 401, processor 402, and communication interface 403 are integrated on a single chip, then the memory 401, processor 402, and communication interface 403 can communicate with each other through an internal interface.

[0103] Processor 402 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0104] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described method for controlling the motor torque of an electric four-wheel drive vehicle.

[0105] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0106] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0107] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0108] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0109] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0110] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0111] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0112] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A method for controlling the motor torque of an electric four-wheel drive vehicle, characterized in that, Includes the following steps: When the electric drive differential of any shaft enters the active protection mode, the difference between the actual torque of that shaft and the current required torque is obtained. The final required torque for the remaining shafts, excluding any one of the shafts, is obtained by superimposing the difference and the initial torque requirement value. as well as When the motor differentials of the other shafts are not in the active protection mode, the motors of the other shafts are controlled to output torque according to the final required torque. When the motor differential of the other shafts enters the active protection mode, it is determined whether the maximum allowable torque under the current wheel speed difference of the other shafts is greater than the final required torque. If the maximum allowable torque is less than the final required torque, then the motors of the remaining shafts are controlled to output torque based on the maximum allowable torque; otherwise, the torque is output based on the final required torque.

2. The method according to claim 1, characterized in that, After controlling the remaining shafts to output torque based on the maximum allowable torque, the method further includes: After a preset time interval, the updated maximum allowable torque of each axle is determined based on the current wheel speed difference of each axle, so as to control the motor of each axle to output torque based on the updated maximum allowable torque.

3. The method according to claim 2, characterized in that, Also includes: Receive differential lock command from user; Based on the differential lock command, the vehicle is controlled to enter the differential lock state, so that the motor output torque of each axle is fully distributed to the wheel end torque output on the side with a higher coefficient of adhesion.

4. The method according to claim 1, characterized in that, Also includes: When the electric differential of any axis does not enter the active protection mode, the motor of any axis is controlled to output torque based on the current required torque.

5. A motor torque control device for an electric four-wheel drive vehicle, characterized in that, include: The acquisition module is used to acquire the difference between the actual torque and the current required torque of any shaft when the electric drive differential of any shaft enters the active protection mode. The superposition module is used to superimpose the difference and the initial torque requirement value to obtain the final required torque of the remaining shafts other than any of the shafts. as well as The control module is used to control the motors of the other shafts to output torque according to the final required torque when the motor differentials of the other shafts have not entered the active protection mode. The judgment module is used to determine whether the maximum allowable torque under the current wheel speed difference of the other shafts is greater than the final required torque when the motor differential of the other shafts enters the active protection mode. The processing module is configured to control the motors of the remaining shafts to output torque based on the maximum allowable torque if the maximum allowable torque is less than the final required torque, and otherwise output torque based on the final required torque.

6. The apparatus according to claim 5, characterized in that, Also includes: The determination module is used to determine the updated maximum allowable torque of each shaft based on the current wheel speed difference of each shaft after controlling the output torque of the remaining shafts based on the maximum allowable torque at preset time intervals, so as to control the motor of each shaft to output torque based on the updated maximum allowable torque.

7. A vehicle, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the motor torque control method for an electric four-wheel drive vehicle as described in any one of claims 1-4.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the motor torque control method for an electric four-wheel drive vehicle as described in any one of claims 1-4.

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