Torque control method and device for dual-motor drive axle

Abstract

The invention discloses a torque control method and device for a dual-motor drive axle, and relates to the field of electric automobile torque control, and the method comprises the steps: correcting the required torque of each motor according to the wheel speed difference value of a follow-up steering axle and a rear axle of the dual-motor drive axle, and correcting the feedback torque of each motor according to the bus voltage, bus current and rotating speed of each motor. And when the corrected demand torque and feedback torque of any motor are different in direction, or the difference value between the corrected demand torque and feedback torque of any motor is larger than a first threshold value, the vehicle enters a non-preparatory driving state, and the safety demand torque of each motor is set to be zero. According to the method, the torque distribution condition of each motor of the dual-motor drive axle is considered, meanwhile, the demand torque and the feedback torque of each motor are corrected, and when the corrected demand torque and feedback torque of each motor do not meet the normal working condition, the vehicle state and the safety demand torque of the motor are controlled, so that the safety of the vehicle is improved. Therefore, the safety of torque control is improved.

Description

Technical Field

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

[0002] With the development of electronic and electrical architecture technology, the powertrain of new energy commercial vehicles has gradually evolved from central drive to electric drive axles and distributed drive. In terms of control, there are multiple links of calculation and interference from internal and external environments from the demand side to the execution side of different power sources. At the same time, there is a certain deviation in the accuracy of the torque of the electric drive assembly at the execution side. Abnormalities in any link will lead to abnormal torque and unexpected acceleration and deceleration of the vehicle, endangering the personal safety of the driver and passengers. Therefore, safe control of torque, especially the safety verification of multi-source power, is very important.

[0003] The 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 an 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 the torque control by comparing the required torque and feedback torque of the motor, but does not verify and correct 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 in 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 combination with the first aspect, in one implementation, 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 combination with the first aspect, in one implementation, the step of correcting the driver's required torque according to a preset required torque range includes:

[0016] If the driver's required torque is greater than the maximum value of the preset required torque range, correcting the driver's required torque to the maximum value of the preset required 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 combination with the first aspect, in one implementation, the method of 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 includes:

[0019] 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;

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

[0021] In combination with the first aspect, in one implementation, 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:

[0022] Within a preset time, a first average wheel speed is calculated according to the wheel speeds of the left wheel and the right wheel corresponding to the follow-up steering axle of the dual-motor drive axle; a second average wheel speed is calculated according to the wheel speeds of the left wheel and the right wheel 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 implementation, the step of 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 according to 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 implementation manner, the corrected required torque and feedback torque of any motor are in different directions, including:

[0028] The corrected demand 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 implementation, 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] The safety required torque of the motor is set to the first product.

[0034] In combination with the first aspect, in one implementation, 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, the transmission instructions of each motor are subjected to E2E verification.

[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, the device comprising:

[0038] A control module, used for controlling 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 according to the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle; and is also used to correct the feedback torque of each motor according to the bus voltage, bus current and speed of each motor;

[0040] The processing module is used to, 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.

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

[0042] This method corrects the demand 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 demand torque and feedback torque of each motor after correction do not meet normal working conditions, the vehicle state and the safe demand 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 solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, 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 the present application clearer, the implementation methods of the present 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 present embodiment comprises the following steps:

[0050] Step S1: Correct 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 demand 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 demand torque and feedback torque of each motor after correction do not meet normal working conditions, the vehicle state and the safe demand torque of the motor are controlled, thereby improving the safety of torque control.

[0055] In some embodiments, before the above 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 a 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 method of correcting the driver's required torque according to a preset required torque range includes the following steps:

[0062] If the driver's demand torque is greater than a maximum value of a 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 required torque is corrected according to the following formula:

[0065]

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

[0067] In this embodiment, T Q After that, the driver's required torque needs to be further corrected according to the vehicle's fault condition. PDCU classifies vehicle faults into three levels according to the fault conditions of each system of the vehicle, namely, minor faults, moderate faults and severe faults, and the 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 follow-up 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, within a preset time, the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle is integrated to obtain a first cumulative difference, including the following steps:

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

[0073] S112: Calculate a second average wheel speed according to the wheel speeds of the left wheel and the right wheel 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, the feedback torque of the motor is corrected 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 according to 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 the above 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, and 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 corrected required torque and feedback torque of any motor are in different directions, including the following situations:

[0097] The corrected demand 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 a 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) verification 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 verification 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 according to 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 according to the bus voltage, bus current and speed of each motor.

[0110] The processing module is used to, 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.

[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 2 is a structural diagram of the above-mentioned vehicle-mounted control system.

[0112] exist Figure 3 In the system, 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 driving input, MTCU and EBS in the form of a CAN (Controller Area Network) bus, and is used to control the above-mentioned dual-motor drive axle according to the corrected required torque of each motor to obtain the feedback torque of each motor. It is also used to correct 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, and correct the feedback torque of each motor according to the bus voltage, bus current and speed of each motor.

[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, and M2 is mounted on the third axle. 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 3-R Connected to EBS.

[0118] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description 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 "first", "second" and "third" to different types.

[0120] In the description of the embodiments of the present application, "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 the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[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; the “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 that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed 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 a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially 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, disk, CD) as described above, and includes a number of instructions for 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 are not intended to 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.

2. The torque control method of the dual-motor drive axle according to claim 1, characterized in that: The required torque of each motor is obtained by: 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 required torque is greater than the maximum value of the preset required torque range, correcting the driver's required torque to the maximum value of the preset required 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 a maximum value of the preset demand torque range.

4. The torque control method of the 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 follow-up steering axle and the rear axle of the dual-motor drive axle includes: 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; When the first cumulative difference is greater than a preset cumulative difference threshold, the required torque of each motor is corrected by a PI deviation control method.

5. The torque control method of the dual-motor drive axle according to claim 4, characterized in that: The method integrates 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, including: Within a preset time, a first average wheel speed is calculated according to the wheel speeds of the left wheel and the right wheel corresponding to the follow-up steering axle of the dual-motor drive axle; a second average wheel speed is calculated according to the wheel speeds of the left wheel and the right wheel 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 the dual-motor drive axle according to claim 1, characterized in that: 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 according to 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.

7. The torque control method of the 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 demand 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.

8. The torque control method of the 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; The safety required torque of the motor is set to the first product.

9. The torque control method of the 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, the transmission instructions of each motor are subjected to E2E verification.

10. A torque control device for a dual-motor drive axle based on the method according to any one of claims 1 to 9, characterized in that: The device comprises: A control module, used for controlling 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 according to the wheel speed difference between the follow-up steering axle and the rear axle of the dual-motor drive axle; and is also used to correct the feedback torque of each motor according to the bus voltage, bus current and speed of each motor; The processing module is used to, 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.

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