A torque control method and device for a dual-motor drive axle

Abstract

A torque control method and device for a dual-motor drive axle relates to the field of torque control for electric vehicles. The method includes: correcting the required torque of each motor based on the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle, and correcting the feedback torque of each motor based on the bus voltage, bus current, and speed of each motor. When the corrected required torque and feedback torque of any motor are in different directions, or the difference between the corrected required torque and feedback torque of any motor is greater than a first threshold, the vehicle enters a non-preparatory driving state and sets the safety required torque of each motor to zero. This method corrects the required torque and feedback torque of each motor while taking into account the torque distribution of each motor in the dual-motor drive axle. When the corrected required torque and feedback torque of each motor do not meet normal operating conditions, the vehicle state and the motor's safety required torque are controlled, thereby improving the safety of torque control.

Description

Technical Field

[0001] The present application relates to the field of torque control of electric vehicles, and specifically to a torque control method and device for a dual-motor drive axle. Background Art

[0002] With the advancement of electronic and electrical architecture technology, new energy commercial vehicle powertrains are gradually evolving from centralized drive to electric drive axles and distributed drive. Controlling torque from the demand side to the execution side of different power sources involves multiple calculation steps and interference from internal and external environments. Furthermore, the accuracy of torque at the execution side of the electric drive assembly can vary. Anomalies in any of these steps can lead to torque anomalies and unexpected acceleration and deceleration, endangering the safety of drivers and passengers. Therefore, safe torque control, especially the safety verification of multiple power sources, is crucial.

[0003] Existing torque safety control technology mainly compares the required torque and feedback torque of the motor to obtain the deviation value between the two, thereby determining whether there is any abnormality in the torque control and handling the abnormality.

[0004] However, the existing torque safety control technology only determines whether there is an abnormality in torque control by comparing the required torque and feedback torque of the motor, without verifying and correcting the required torque and feedback torque of the motor. At the same time, the torque distribution of each motor in the dual-motor drive axle is not taken into account during the torque control process, which seriously affects the safety of torque control. Summary of the Invention

[0005] The present application provides a torque control method and device for a dual-motor drive axle, which can verify and correct the required torque and feedback torque of the motor, while taking into account the torque distribution of each motor of the dual-motor drive axle during the torque control process, thereby improving the safety of torque control.

[0006] In a first aspect, an embodiment of the present application provides a torque control method for a dual-motor drive axle, the method comprising:

[0007] According to the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle, the required torque of each motor is corrected;

[0008] Controlling the dual-motor drive axle according to the corrected required torque of each motor to obtain feedback torque of each motor;

[0009] Correct the feedback torque of each motor according to the bus voltage, bus current and speed of each motor;

[0010] When the corrected required torque and feedback torque of any motor are in different directions, or the difference between the corrected required torque and feedback torque of any motor is greater than a first threshold, the vehicle enters a non-preparatory driving state and sets the safety required torque of each motor to zero.

[0011] In conjunction with the first aspect, in one embodiment, a method for obtaining the required torque of each motor includes:

[0012] Calculate the driver's required torque based on the vehicle's accelerator pedal opening, brake pedal opening and current speed;

[0013] Correcting the driver's required torque according to a preset required torque range;

[0014] The required torque of each motor is calculated based on the corrected driver's required torque and the preset torque distribution strategy.

[0015] In conjunction with the first aspect, in one embodiment, the step of correcting the driver's required torque according to a preset required torque range includes:

[0016] If the driver's demand torque is greater than the maximum value of the preset demand torque range, correcting the driver's demand torque to the maximum value of the preset demand torque range;

[0017] If the driver's demand torque is less than a minimum value of the preset demand torque range, the driver's demand torque is corrected to a maximum value of the preset demand torque range.

[0018] In conjunction with the first aspect, in one embodiment, the step of correcting the required torque of each motor according to the wheel speed difference between the follower steering axle and the rear axle of the dual-motor drive axle includes:

[0019] Integrating the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle within a preset time to obtain a first cumulative difference;

[0020] When the first cumulative difference is greater than a preset cumulative difference threshold, the required torque of each motor is corrected using a PI deviation control method.

[0021] In combination with the first aspect, in one embodiment, integrating the wheel speed difference between the follower steering axle and the rear axle of the dual-motor drive axle within a preset time to obtain the first cumulative difference includes:

[0022] Within a preset time, a first average wheel speed is calculated based on the wheel speeds of the left and right wheels corresponding to the follow-up steering axle of the dual-motor drive axle; a second average wheel speed is calculated based on the wheel speeds of the left and right wheels corresponding to the rear axle of the dual-motor drive axle;

[0023] Within a preset time, the difference between the first average wheel speed and the second average wheel speed is integrated to obtain a first cumulative difference.

[0024] In combination with the first aspect, in one embodiment, the correcting the feedback torque of each motor according to the bus voltage, bus current, and speed of each motor includes:

[0025] Calculate the estimated torque of each motor based on the bus voltage, bus current and speed of each motor;

[0026] For any motor, if the difference between the estimated torque and the feedback torque of the motor is greater than a preset first percentage value, the feedback torque of the motor is corrected to an average of the estimated torque and the feedback torque of the motor.

[0027] In combination with the first aspect, in one embodiment, the corrected required torque and feedback torque of any motor are in different directions, including:

[0028] The corrected required torque of any motor is greater than zero and the feedback torque is less than zero;

[0029] Alternatively, the corrected required torque of any motor is less than zero and the feedback torque is greater than zero.

[0030] In combination with the first aspect, in one embodiment, when the difference between the corrected required torque and the feedback torque of any motor is less than a first threshold, the method further includes:

[0031] Obtaining a first safety torque coefficient according to a ratio of the corrected required torque and feedback torque of the motor;

[0032] Obtaining a first product of the corrected required torque of the motor and a first safety torque coefficient;

[0033] Set the safety required torque of the motor to the first product.

[0034] In conjunction with the first aspect, in one embodiment, the method further includes:

[0035] Add counter and CRC information to the transmission instructions of each motor;

[0036] When the dual-motor drive bridge is working, E2E verification is performed on the transmission instructions of each motor.

[0037] In a second aspect, an embodiment of the present application provides a torque control device for a dual-motor drive axle based on any one of the methods described above, the device comprising:

[0038] a control module, configured to control the dual-motor drive axle according to the corrected required torque of each motor to obtain feedback torque of each motor;

[0039] A correction module is used to correct the required torque of each motor based on the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle; it is also used to correct the feedback torque of each motor based on the bus voltage, bus current and speed of each motor;

[0040] The processing module is used to, when the directions of the corrected required torque and the feedback torque of any motor are different, or the difference between the corrected required torque and the feedback torque of any motor is greater than a first threshold, cause the vehicle to enter a non-preparatory driving state and set the safety required torque of each motor to zero.

[0041] The beneficial effects of the technical solutions provided in the embodiments of the present application include:

[0042] This method corrects the required torque and feedback torque of each motor while taking into account the torque distribution of each motor in the dual-motor drive axle. When the required torque and feedback torque of each motor after correction do not meet normal working conditions, the vehicle state and the safe required torque of the motor are controlled, thereby improving the safety of torque control. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is a flow chart of a torque control method for a dual-motor drive axle according to an embodiment of the present application;

[0044] Figure 2 This is a schematic structural diagram of a torque control device for a dual-motor drive axle according to an embodiment of the present application;

[0045] Figure 3 This is a schematic diagram of the structure of the vehicle control system according to an embodiment of the present application;

[0046] Figure 4 This is a schematic diagram of the structure of the dual-motor drive axle according to an embodiment of the present application. DETAILED DESCRIPTION

[0047] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0048] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0049] First, please refer to Figure 1 , Figure 1The figure is a flow chart of the torque control method of the dual-motor drive axle according to the embodiment of the present application. The torque control method of the dual-motor drive axle provided in the embodiment of the present application includes the following steps:

[0050] Step S1: Correcting the required torque of each motor according to the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle.

[0051] Step S2: Control the dual-motor drive axle according to the corrected required torque of each motor to obtain the feedback torque of each motor.

[0052] Step S3: Correct the feedback torque of each motor according to the bus voltage, bus current and speed of each motor.

[0053] Step S4: When the corrected required torque and feedback torque of any motor are in different directions, or the difference between the corrected required torque and feedback torque of any motor is greater than a first threshold, the vehicle enters a non-preparatory driving state and sets the safety required torque of each motor to zero.

[0054] This method corrects the required torque and feedback torque of each motor while taking into account the torque distribution of each motor in the dual-motor drive axle. When the required torque and feedback torque of each motor after correction do not meet normal working conditions, the vehicle state and the safe required torque of the motor are controlled, thereby improving the safety of torque control.

[0055] In some embodiments, before step S1, obtaining the required torque of each motor includes the following steps:

[0056] First, the driver's required torque is calculated based on the vehicle's accelerator pedal opening, brake pedal opening, and current speed.

[0057] Thereafter, the driver's required torque is corrected according to the preset required torque range.

[0058] Finally, the required torque of each motor is calculated based on the corrected driver's required torque and the preset torque distribution strategy.

[0059] It should be noted that, in the above steps, the accelerator pedal opening, brake pedal opening and current speed of the vehicle are obtained through the PDCU (Power Domain Control Unit).

[0060] In some embodiments, when calculating the driver's required torque, it is necessary to take into account the vehicle's control mode, such as power mode, economy mode, smart mode, etc.

[0061] In some embodiments, the above-mentioned step of correcting the driver's required torque according to the preset required torque range includes the following steps:

[0062] If the driver's demand torque is greater than a maximum value of the preset demand torque range, the driver's demand torque is corrected to the maximum value of the preset demand torque range.

[0063] If the driver's demand torque is less than a minimum value of the preset demand torque range, the driver's demand torque is corrected to a maximum value of the preset demand torque range.

[0064] In a more specific embodiment, the driver's demand torque is corrected according to the following formula:

[0065]

[0066] In formula (1), T Q is the corrected driver's demand torque, T b is the driver's demand torque before correction, and the preset demand torque range is [λ1, λ2].

[0067] In this embodiment, T Q After that, the driver's required torque needs to be further adjusted according to the vehicle's fault conditions. PDCU classifies vehicle faults into three levels: minor faults, moderate faults, and severe faults, with corresponding torque limit thresholds T a They are 20%, 40% and 60% of the preset reference value respectively. Finally, the driver's demand torque T after the second correction is r =Min(T Q ,T a ).

[0068] In some embodiments, in the above step S1, the required torque of each motor is corrected according to the wheel speed difference between the follower steering axle and the rear axle of the dual-motor drive axle, including the following steps:

[0069] S11: Integrate the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle within a preset time to obtain a first cumulative difference.

[0070] S12: When the first cumulative difference is greater than a preset cumulative difference threshold, the required torque of each motor is corrected by a PI (Proportional-Integral) deviation control method.

[0071] In some embodiments, in the above step S11, integrating the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle within a preset time to obtain a first cumulative difference includes the following steps:

[0072] S111: Calculate a first average wheel speed according to the wheel speeds of the left and right wheels corresponding to the follower steering axle of the dual-motor drive axle within a preset time.

[0073] S112: Calculating a second average wheel speed according to the wheel speeds of the left and right wheels corresponding to the rear axle of the dual-motor drive axle within a preset time.

[0074] S113: Integrate the difference between the first average wheel speed and the second average wheel speed within a preset time to obtain a first cumulative difference.

[0075] In a more specific embodiment, in the above step S111, the formula for calculating the first average wheel speed is as follows:

[0076]

[0077] In formula (2), ω1 is the first average wheel speed, ω 1-L is the left wheel speed corresponding to the follower steering axle of the motor-driven axle, ω 1-R It is the right wheel speed corresponding to the follower steering axle of the motor-driven axle.

[0078] In a more specific embodiment, in the above step S112, the formula for calculating the second average wheel speed is as follows:

[0079]

[0080] In formula (3), ω3 is the second average wheel speed, ω 3-L is the left wheel speed corresponding to the rear axle of the dual-motor drive axle, ω 3-R It is the right wheel speed corresponding to the rear axle of the dual-motor drive axle.

[0081] In a more specific embodiment, in the above step S113, the formula for calculating the difference between the first average wheel speed and the second average wheel speed is as follows:

[0082] Δω=|ω1-ω3|Formula (4)

[0083] In formula (4), Δω is the difference between the first average wheel speed and the second average wheel speed.

[0084] In a more specific embodiment, in the above step S12, the required torque of each motor is corrected by the PI deviation control method, and the specific formula is as follows: r ′=T r +K p Δω+K i ∫Δωdt formula (5)

[0085] In formula (5), T r ′ is the corrected required torque of any motor, T r is the required torque of the motor before correction, K p is the error proportional factor, K i is the integration parameter. Kp and K i Both can be adjusted according to the actual calibration situation.

[0086] In some embodiments, in the above step S3, the feedback torque of each motor is corrected according to the bus voltage, bus current and speed of each motor, including the following steps:

[0087] S31: Calculate the estimated torque of each motor according to the bus voltage, bus current and speed of each motor.

[0088] S32: For any motor, if the difference between the estimated torque and the feedback torque of the motor is greater than a preset first percentage value, correct the feedback torque of the motor to an average of the estimated torque and the feedback torque of the motor.

[0089] In a more specific embodiment, in the above step S1, the formula for calculating the estimated torque of each motor is as follows based on the bus voltage, bus current and speed of each motor:

[0090]

[0091] In formula (6), T e is the estimated torque of a motor, η is the efficiency coefficient, which can be calibrated according to the bench data of the motor, U is the bus voltage of the motor, I is the bus current of the motor, and n is the speed of the motor.

[0092] In a more specific embodiment, in step S2, for any motor, if the difference between the estimated torque and the feedback torque of the motor is greater than a preset first percentage value, the feedback torque of the motor is corrected to the average of the estimated torque and the feedback torque of the motor. The specific process is as follows:

[0093] Assume that the estimated torque of a motor is T e , the feedback torque of the motor is T M .

[0094] when , the estimated torque of the motor is considered to be equal to the feedback torque and no correction is required.

[0095] when When the feedback torque of the motor is corrected to (T e +T M ) / 2.

[0096] In some embodiments, in the above step S4, the directions of the corrected required torque and the feedback torque of any motor are different, including the following situations:

[0097] The corrected required torque of any motor is greater than zero and the feedback torque is less than zero;

[0098] Alternatively, the corrected required torque of any motor is less than zero and the feedback torque is greater than zero.

[0099] In some embodiments, when the difference between the corrected required torque and the feedback torque of any motor is less than a first threshold, the method further includes:

[0100] First, obtain a first safety torque coefficient according to the ratio of the corrected required torque and the feedback torque of the motor.

[0101] After that, obtain the first product of the corrected required torque of the motor and the first safety torque coefficient.

[0102] Finally, set the safety required torque of the motor to the first product.

[0103] In a more specific embodiment, assume that the corrected required torque of a certain motor is T r ′, the corrected feedback torque of the motor is T m , the first threshold is b, the first safety torque coefficient is β, when ∫|T r ′-T m |<b, set the safety required torque T rf of the motor to βT r ′.

[0104] In some embodiments, the above method further includes:

[0105] Add counter and CRC (Cyclic Redundancy Check) information to the transmission instructions of each motor, and then perform E2E (End to End) check on the transmission instructions of each motor when the above dual-motor drive axle is working.

[0106] Preferably, the counter can be set to a cycle between 0 and 15, and the CRC can adopt AUTOSAR E2E Profile2, or other AUTOSAR E2E technologies can be used as the E2E check solution.

[0107] In a second aspect, please refer to Figure 2 , Figure 2 which is a schematic structural diagram of the torque control device of the dual-motor drive axle according to the embodiment of the present application. The torque control device of the dual-motor drive axle provided in this embodiment includes the following modules:

[0108] A control module, configured to control the above dual-motor drive axle according to the corrected required torque of each motor, and obtain the feedback torque of each motor.

[0109] The correction module is used to correct the required torque of each motor based on the wheel speed difference between the follower steering axle and the rear axle of the dual-motor drive axle. It is also used to correct the feedback torque of each motor based on the bus voltage, bus current, and speed of each motor.

[0110] The processing module is used to, when the directions of the corrected required torque and the feedback torque of any motor are different, or the difference between the corrected required torque and the feedback torque of any motor is greater than a first threshold, cause the vehicle to enter a non-preparatory driving state and set the safety required torque of each motor to zero.

[0111] In some embodiments, the functions of the control module and the correction module in the above device are realized by a vehicle-mounted control system. Figure 3 , Figure 3 This is a structural diagram of the above-mentioned vehicle control system.

[0112] exist Figure 3 In the system, the MTCU (Motor and Transmission Control Unit), PDCU and EBS (Electronic Brake System) are all installed on the vehicle side and connected to the dual-motor drive axle.

[0113] The MTCU is responsible for collecting the bus voltage, bus current and speed of each motor and obtaining the required torque of each motor before correction.

[0114] The PDCU is connected to the vehicle's driving input, MTCU, and EBS via a CAN (Controller Area Network) bus. It controls the dual-motor drive axle based on the corrected required torque of each motor, generating feedback torque from each motor. It also corrects the required torque of each motor based on the wheel speed difference between the servo steering axle and the rear axle of the dual-motor drive axle, and corrects the feedback torque of each motor based on its bus voltage, bus current, and speed.

[0115] EBS is responsible for collecting the wheel speed of the follow-up steering axle and rear axle through the wheel speed sensors installed on the dual-motor drive axle.

[0116] In this embodiment, please refer to the architecture of the dual-motor drive axle. Figure 4 , Figure 4 This is a schematic diagram of the structure of the dual-motor drive axle according to an embodiment of the present application.

[0117] exist Figure 4 In the figure, M1 is the front electric drive axle assembly, M2 is the rear electric drive axle assembly, the first axle is the follow-up steering axle, the third axle is the rear axle, M1 is mounted on the second axle, M2 is mounted on the third axle, ω 1-L is the left wheel speed sensor of the first bridge, ω 1-Ris the right wheel speed sensor of the first bridge, ω 3-L is the left wheel speed sensor of the third bridge, ω 3-R is the right wheel speed sensor of the third bridge, the above ω 1-L 、ω 1-R 、ω 3-L and ω 3-R Connected to EBS.

[0118] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0119] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit the "first", "second" and "third" to different types.

[0120] In the description of the embodiments of this application, the words "exemplary," "for example," or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary," "for example," or "for example" in the embodiments of this application should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary," "for example," or "for example" is intended to present the relevant concepts in a concrete manner.

[0121] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0122] In some processes described in the embodiments of the present application, multiple operations or steps are included that appear in a specific order. However, it should be understood that these operations or steps may not be performed in the order in which they appear in the embodiments of the present application or may be performed in parallel. The sequence numbers of the operations are only used to distinguish between different operations, and the sequence numbers themselves do not represent any order of execution. In addition, these processes may include more or fewer operations, and these operations or steps may be performed in sequence or in parallel, and these operations or steps may be combined.

[0123] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, of course, it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes a number of instructions for enabling a terminal device to execute the methods described in each embodiment of the present application.

[0124] The above are only preferred embodiments of the present application and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A torque control method for a dual-motor drive axle, characterized in that: The method comprises: According to the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle, the required torque of each motor is corrected; Controlling the dual-motor drive axle according to the corrected required torque of each motor to obtain feedback torque of each motor; Correct the feedback torque of each motor according to the bus voltage, bus current and speed of each motor; When the corrected required torque and feedback torque of any motor are in different directions, or the difference between the corrected required torque and feedback torque of any motor is greater than a first threshold, the vehicle enters a non-preparatory driving state and sets the safety required torque of each motor to zero; The step of correcting the feedback torque of each motor according to the bus voltage, bus current, and speed of each motor includes: Calculate the estimated torque of each motor based on the bus voltage, bus current and speed of each motor; For any motor, if the difference between the estimated torque and the feedback torque of the motor is greater than a preset first percentage value, the feedback torque of the motor is corrected to an average of the estimated torque and the feedback torque of the motor.

2. The torque control method of a dual-motor drive axle according to claim 1, characterized in that: Methods for obtaining the required torque of each motor include: Calculate the driver's required torque based on the vehicle's accelerator pedal opening, brake pedal opening and current speed; Correcting the driver's required torque according to a preset required torque range; The required torque of each motor is calculated based on the corrected driver's required torque and the preset torque distribution strategy.

3. The torque control method of the dual-motor drive axle according to claim 2, characterized in that: The step of correcting the driver's required torque according to the preset required torque range includes: If the driver's demand torque is greater than the maximum value of the preset demand torque range, correcting the driver's demand torque to the maximum value of the preset demand torque range; If the driver's demand torque is less than a minimum value of the preset demand torque range, the driver's demand torque is corrected to the minimum value of the preset demand torque range.

4. The torque control method of a dual-motor drive axle according to claim 1, characterized in that: The method of correcting the required torque of each motor according to the wheel speed difference between the follower steering axle and the rear axle of the dual-motor drive axle includes: Integrating the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle within a preset time to obtain a first cumulative difference; When the first cumulative difference is greater than a preset cumulative difference threshold, the required torque of each motor is corrected using a PI deviation control method.

5. The torque control method of a dual-motor drive axle according to claim 4, characterized in that: The method of integrating the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle within a preset time to obtain a first cumulative difference includes: Within a preset time, a first average wheel speed is calculated based on the wheel speeds of the left and right wheels corresponding to the follow-up steering axle of the dual-motor drive axle; a second average wheel speed is calculated based on the wheel speeds of the left and right wheels corresponding to the rear axle of the dual-motor drive axle; Within a preset time, the difference between the first average wheel speed and the second average wheel speed is integrated to obtain a first cumulative difference.

6. The torque control method of a dual-motor drive axle according to claim 1, characterized in that: The corrected required torque and feedback torque of any motor are in different directions, including: The corrected required torque of any motor is greater than zero and the feedback torque is less than zero; Alternatively, the corrected required torque of any motor is less than zero and the feedback torque is greater than zero.

7. The torque control method of a dual-motor drive axle according to claim 1, characterized in that: When the difference between the corrected required torque and the feedback torque of any motor is less than a first threshold, the method further includes: Obtaining a first safety torque coefficient according to a ratio of the corrected required torque and feedback torque of the motor; Obtaining a first product of the corrected required torque of the motor and a first safety torque coefficient; Set the safety required torque of the motor to the first product.

8. The torque control method of a dual-motor drive axle according to claim 1, characterized in that: Also includes: Add counter and CRC information to the transmission instructions of each motor; When the dual-motor drive bridge is working, E2E verification is performed on the transmission instructions of each motor.

9. A torque control device for a dual-motor drive axle for implementing the method according to any one of claims 1 to 8, characterized in that: The device comprises: a control module, configured to control the dual-motor drive axle according to the corrected required torque of each motor to obtain feedback torque of each motor; A correction module is used to correct the required torque of each motor based on the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle; it is also used to correct the feedback torque of each motor based on the bus voltage, bus current and speed of each motor; The processing module is used to, when the directions of the corrected required torque and the feedback torque of any motor are different, or the difference between the corrected required torque and the feedback torque of any motor is greater than a first threshold, cause the vehicle to enter a non-preparatory driving state and set the safety required torque of each motor to zero.

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