Four-wheel hub motor drive vehicle energy-saving torque distribution method considering motor fault

Abstract

The application discloses a four-wheel hub motor drive vehicle energy-saving torque distribution method considering motor faults, and relates to the technical field of new energy vehicles, and comprises the following steps: obtaining actual output torque of a motor according to sensing signals of four-wheel hub motors by using a fault mode identification module, and judging a motor fault mode category in combination with voltage, current, motor temperature, motor driver temperature and actual demand torque of the motor; selecting a fault mode control mode; performing target optimization by using an energy-saving distribution strategy optimization target function and constraint module; and obtaining a four-wheel hub motor drive vehicle energy-saving torque distribution result by using an optimization solving module. The application solves the problem that traditional torque distribution ignores the differences in efficiencies of various motors, and it is difficult to guarantee energy utilization rate in the case of motor faults or performance degradation.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle technology, and in particular to an energy-saving torque distribution method for four-wheel hub motor driven vehicles that takes into account motor failure. Background Technology

[0002] Driven by national energy strategies, new energy vehicles have become a key focus of the automotive industry. Four-wheel in-wheel motor drive vehicles, as an important direction in new energy vehicles, offer better handling compared to traditional central drive and traditional four-wheel drive systems. The torque distribution in four-wheel in-wheel motor drive vehicles directly determines the vehicle's overall energy consumption and handling stability, and has been a subject of considerable research attention. Traditional torque distribution methods primarily rely on factors such as vehicle dynamic performance requirements, road conditions, and vehicle status to achieve optimal driving performance. However, in practical applications, four-wheel in-wheel motor drive vehicles may face motor failure. Motor failure can lead to the failure or reduced torque of some drive wheels, thus affecting vehicle performance and safety.

[0003] Due to factors such as manufacturing processes, operating conditions, and motor replacement, the optimal operating ranges of the four in-wheel motors often vary. Traditional torque distribution methods ignore the differences in efficiency among the motors, easily leading to some motors operating at low efficiency, reducing the overall energy utilization of the vehicle and negatively impacting its range. Furthermore, in-wheel motors operate in harsh environments; weather, vibration, water, and dust can all easily cause motor malfunctions or performance degradation. Traditional torque distribution methods cannot guarantee optimal energy utilization for all four in-wheel motors under conditions of malfunction or performance degradation. Summary of the Invention

[0004] In view of the above-mentioned shortcomings in the prior art, the energy-saving torque distribution method for four-wheel hub motor driven vehicles that takes into account motor failure provided by the present invention solves the problem that traditional torque distribution ignores the differences in efficiency of each motor and is difficult to guarantee energy utilization in the event of motor failure or performance degradation.

[0005] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows: a method for energy-saving torque distribution in a four-wheel hub motor driven vehicle considering motor failure, comprising the following steps:

[0006] S1: The fault mode identification module obtains the actual output torque of the motor based on the sensor signals of the four-wheel hub motor, and determines the motor fault mode category by combining the motor voltage, current, motor temperature, motor driver temperature and the actual torque required by the motor.

[0007] S2: Select the fault mode control method according to the motor fault mode category;

[0008] S3: Based on the selected fault mode control method, the objective function and constraint module are optimized using the energy-saving allocation strategy to perform objective optimization;

[0009] S4: Based on the optimization results, the energy-saving torque distribution results of the four-wheel hub motor driven vehicle are obtained using the optimization solution module, and the energy-saving torque distribution of the four-wheel hub motor driven vehicle considering motor failure is completed.

[0010] The beneficial effects of the above solution are as follows: This invention proposes an energy-saving torque distribution method for four-wheel hub motor driven vehicles that considers motor failure modes. It mainly consists of four steps: failure mode identification, failure mode control mode selection, energy-saving distribution strategy optimization objective function and constraints, and optimization solution. By considering the differences in motor efficiency and optimizing torque distribution according to different failure modes, more efficient energy utilization is achieved, the vehicle's range is improved, and the problem of traditional torque distribution ignoring the differences in efficiency of each motor and making it difficult to guarantee energy utilization in the event of motor failure or performance degradation is solved.

[0011] Furthermore, the motor fault mode categories in S2 include normal mode, complete failure mode, and performance limitation mode;

[0012] Complete failure modes include single motor failure, same-side dual motor failure, opposite-side coaxial dual motor failure, opposite-side opposite-axis dual motor failure, three-motor failure, and four-motor failure;

[0013] Performance limiting modes include speed or torque limiting for single motor failure, speed or torque limiting for dual motor failure on the same side, speed or torque limiting for dual motor failure on opposite sides and coaxial sides, speed or torque limiting for dual motor failure on opposite sides and opposite axes, speed or torque limiting for three motor failures, and speed or torque limiting for four motor failures.

[0014] The beneficial effect of the above-mentioned further solutions is that the present invention classifies motor faults into the above-mentioned multiple modes, which are used to control different modes separately in the future.

[0015] Furthermore, the control method in normal mode is as follows: control is performed according to the normal control state, the torque of the four motors is the maximum torque of the motors, and the target optimization is performed in the energy-saving allocation strategy optimization objective function and constraint module;

[0016] The control method for single motor failure is as follows: perform normal driving to achieve straight-line driving, and then enter the energy-saving allocation strategy optimization objective function and constraint module for objective optimization;

[0017] The control method for dual-motor faults on the same side is as follows: if there is a deviation, control is performed in conjunction with steering, and energy-saving allocation is performed on the two normal motors. The objective function and constraint module for energy-saving allocation strategy optimization are then used for objective optimization.

[0018] The control methods for dual motor failures on opposite sides and dual motor failures on opposite sides are as follows: normal drive, additional yaw torque is achieved through differential torque distribution, and the target optimization is performed by entering the energy-saving distribution strategy optimization objective function and constraint module.

[0019] The control method for three-motor faults is: low-speed limp driving, without entering the energy-saving allocation strategy optimization objective function and constraint module;

[0020] The control method for four-motor faults is as follows: stop the vehicle and enter the energy-saving allocation strategy optimization objective function and constraint module for objective optimization;

[0021] The control method for the performance-limited mode is as follows: torque distribution optimization is performed within the limited speed and torque range, and the objective function and constraint module for energy-saving distribution strategy optimization are then entered for objective optimization.

[0022] The beneficial effects of the above-mentioned further solutions are: through the above technical solutions, corresponding control methods are set for different fault modes of the motor, and it is determined whether to enter the energy-saving allocation strategy optimization objective function and constraint module.

[0023] Furthermore, the objective function and constraint formulas for the energy-saving allocation strategy optimization objective function and constraint module in S3 are as follows:

[0024]

[0025] Where min represents taking the minimum value, P bat_dem For battery output power, T FL T represents the torque of the left front wheel motor. FR T represents the torque of the right front wheel motor. RL T represents the torque of the left rear wheel motor. RR η is the torque of the right rear wheel motor, ω is the rotational speed, and η is the torque of the right rear wheel FL For the efficiency of the left front wheel motor, η FR For the efficiency of the right front wheel motor, η RL For the efficiency of the left rear wheel motor, η RR For the efficiency of the right rear wheel motor, T demand T represents the total torque required by the vehicle. FL_able T represents the maximum torque of the left front wheel motor. FR_able T represents the maximum torque of the right front wheel motor. RL_able T represents the maximum torque of the left rear wheel motor. RR_able V represents the maximum torque of the right rear wheel motor. oc I is the battery open-circuit voltage. bat For current, r w Where is the wheel radius, μ is the road adhesion coefficient, and F z_FL For the vertical load of the left front wheel motor, F z_FR For the vertical load of the right front wheel motor, F z_RLFor the vertical load of the left rear wheel motor, F z_RR For the vertical load of the right rear wheel motor, ΔM z Let yaw moment be denoted by 'a', distance from center of mass to front axle be 'δ', wheel angle be 'B', track width be 'f', and 'a' be 'f'. η_FL (·) represents the efficiency map characteristic of the left front wheel motor, f η_FR (·) represents the efficiency map characteristic of the right front wheel motor, f η_RL (·) represents the efficiency map characteristic of the left rear wheel motor, f η_RR (·) represents the efficiency map characteristic of the right rear wheel motor.

[0026] The beneficial effect of the above-mentioned further solution is that it provides the objective function P for the vehicle during its driving process. bat_dem The constraints include total demand torque constraints, motor drive torque constraints, battery power constraints, ground adhesion constraints, and yaw moment constraints.

[0027] Furthermore, the final optimization allocation problem of the optimization solution module in S4 is simplified to T FR T RL and T RR This is a spatial plane optimization problem for coordinate axes, and the goal is to find the optimal three-dimensional spatial coordinate point P within the solution space set that satisfies the aforementioned constraints. best The formula is:

[0028]

[0029] The beneficial effect of the above-mentioned further solutions is that, through the above technical solutions, the final optimization allocation problem is transformed into a spatial plane optimization problem, and an optimized solution is achieved.

[0030] Furthermore, the optimization solution employs online traversal optimization, which includes the following steps:

[0031] S4-1: T FR and T RL Divide the sample into N and M equal parts at equal intervals, and calculate the T value for each part using relevant formulas. FR and T RL T in combination FR and T RL The relevant formula is:

[0032] T demand =T FL +T FR +T RL +T RR

[0033] D = AT FR +BT RL +CT RR

[0034] Where A, B, C, and D are all constants;

[0035] S4-2: Determine whether each combination satisfies the constraints. If so, calculate P. bat_dem If not, then P bat_dem It is infinitely large;

[0036] S4-3: Repeat steps S4-1 and S4-2 above to obtain an N*M matrix P. bat_dem And determine matrix P bat_dem The row k1 and column k2 of the matrix corresponding to the minimum value are used to obtain the energy-saving torque distribution result of the four-wheel hub motor driven vehicle. The formula is as follows:

[0037]

[0038] The beneficial effects of the above-mentioned further scheme are: by adopting online traversal optimization, the torque distribution optimization solution is completed, the most energy-efficient torque distribution solution is obtained, and energy efficiency is improved. Attached Figure Description

[0039] Figure 1 Flowchart of an energy-saving torque distribution method for four-wheel hub motor driven vehicles, taking into account motor failure.

[0040] Figure 2 This is a diagram illustrating the overall technical solution of the present invention.

[0041] Figure 3 This is a schematic diagram of the fault mode recognition principle.

[0042] Figure 4 This is a diagram of the dynamics model of a vehicle driven by four-wheel hub motors.

[0043] Figure 5 This is a schematic diagram of spatial planar optimization.

[0044] Figure 6 The external characteristic curves of the four motors are shown.

[0045] Figure 7 Efficiency map curves for the four motors.

[0046] Figure 8 This is a graph showing the internal resistance characteristics of the battery.

[0047] Figure 9 This is a graph showing the open-circuit voltage characteristic of the battery. Detailed Implementation

[0048] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0049] like Figure 1and Figure 2 As shown, an energy-saving torque distribution method for a four-wheel hub motor driven vehicle considering motor failure includes the following steps:

[0050] S1: The fault mode identification module obtains the actual output torque of the motor based on the sensor signals of the four-wheel hub motor, and determines the motor fault mode category by combining the motor voltage, current, motor temperature, motor driver temperature and the actual torque required by the motor.

[0051] S2: Select the fault mode control method according to the motor fault mode category;

[0052] S3: Based on the selected fault mode control method, the objective function and constraint module are optimized using the energy-saving allocation strategy to perform objective optimization;

[0053] S4: Based on the optimization results, the energy-saving torque distribution results of the four-wheel hub motor driven vehicle are obtained using the optimization solution module, and the energy-saving torque distribution of the four-wheel hub motor driven vehicle considering motor failure is completed.

[0054] Fault mode identification module, such as Figure 3 As shown, the actual output torque T of the motor is obtained by observing the motor torque based on sensor signals from wheel speed sensors, vehicle speed sensors, yaw rate sensors, and ambient temperature sensors. real (Observers include, but are not limited to, neural networks, support vector machines, Kalman filters and their various improved filters, Romberg observers, etc., mainly using various vehicle signals to measure the actual output torque T of the motor.) real (Estimation is performed), and combined with the motor's voltage U, current I, and the motor and its driver temperature T. temp and its actual required torque T * Determine the fault mode category ID.

[0055] The motor fault mode categories in S2 include normal mode, complete failure mode, and performance limitation mode;

[0056] Complete failure modes include single motor failure, same-side dual motor failure, opposite-side coaxial dual motor failure, opposite-side opposite-axis dual motor failure, three-motor failure, and four-motor failure;

[0057] Performance limiting modes include speed or torque limiting for single motor failure, speed or torque limiting for dual motor failure on the same side, speed or torque limiting for dual motor failure on opposite sides and coaxial sides, speed or torque limiting for dual motor failure on opposite sides and opposite axes, speed or torque limiting for three motor failures, and speed or torque limiting for four motor failures.

[0058] The control method in normal mode is as follows: control is performed according to the normal control state, the torque of the four motors is the maximum torque of the motors, and the energy-saving allocation strategy optimization objective function and constraint module is entered for objective optimization;

[0059] The control method for single motor failure is as follows: perform normal driving to achieve straight-line driving, and then enter the energy-saving allocation strategy optimization objective function and constraint module for objective optimization;

[0060] The control method for dual-motor faults on the same side is as follows: if there is a deviation, control is performed in conjunction with steering, and energy-saving allocation is performed on the two normal motors. The objective function and constraint module for energy-saving allocation strategy optimization are then used for objective optimization.

[0061] The control methods for dual motor failures on opposite sides and dual motor failures on opposite sides are as follows: normal drive, additional yaw torque is achieved through differential torque distribution, and the target optimization is performed by entering the energy-saving distribution strategy optimization objective function and constraint module.

[0062] The control method for three-motor faults is: low-speed limp driving, without entering the energy-saving allocation strategy optimization objective function and constraint module;

[0063] The control method for four-motor faults is as follows: stop the vehicle and enter the energy-saving allocation strategy optimization objective function and constraint module for objective optimization;

[0064] The control method for the performance-limited mode is as follows: torque distribution optimization is performed within the limited speed and torque range, and the objective function and constraint module for energy-saving distribution strategy optimization are then entered for objective optimization.

[0065] The objective function and constraint formulas for the energy-saving allocation strategy optimization objective function and constraint module in S3 are as follows:

[0066] The objective function for the vehicle during its movement is:

[0067]

[0068] Constraint 1, the total required torque constraint is:

[0069] T demand =T FL +T FR +T RL +T RR

[0070] Constraint 2, motor drive torque constraint, that is, the torque of the four motors should be less than the maximum value of each motor:

[0071]

[0072] Constraint 3, Battery power constraint:

[0073] Battery open circuit voltage V oc With battery SOC b The functional relationship of (t) was obtained experimentally:

[0074]

[0075] Among them, SOC b (t0) is the initial value of the battery, Q max The maximum battery capacity is given by f, where t0 is the initial time, t is the current time, and f is the current time. soc_v (·) represents the voltage as a function of SOC. b The nonlinear function that varies with t can be obtained experimentally;

[0076]

[0077] Among them, R int For internal resistance, P bat_req For load power;

[0078] Battery output power P bat_dem for:

[0079] P bat_dem ≤V oc I bat

[0080] Constraint 4, Ground Adhesion Constraint, i.e., the ground driving force is less than the ground adhesion force:

[0081]

[0082]

[0083] Where m is the total vehicle mass, g is the acceleration due to gravity, b is the distance from the center of mass to the rear axle, l is the wheelbase, and h is the acceleration due to gravity. g Let a be the height of the center of mass. x For longitudinal acceleration, a y This is lateral acceleration.

[0084] Constraint condition 5, yaw moment constraint, such as Figure 4 As shown:

[0085]

[0086] Among them, F xi (i = 1, 2, 3, 4) represent the longitudinal forces of each wheel, F yi (i = 1, 2, 3, 4) represent the lateral forces of each wheel, σ is the front wheel steering angle, V is the vehicle speed, μ is the longitudinal vehicle speed, v is the lateral vehicle speed, and γ is the yaw rate. The relationship between the longitudinal forces of each wheel and the torques of each wheel is as follows:

[0087]

[0088] Combining the above formulas, the yaw moment constraint can be obtained as follows:

[0089]

[0090] In summary, the energy-saving torque distribution problem for a four-wheel hub motor driven vehicle considering motor failure modes is transformed into an optimization problem with the following objective function and constraints:

[0091]

[0092] Where min represents taking the minimum value, P bat_dem For battery output power, T FL T represents the torque of the left front wheel motor. FR T represents the torque of the right front wheel motor. RL T represents the torque of the left rear wheel motor. RR η is the torque of the right rear wheel motor, ω is the rotational speed, and η is the torque of the right rear wheel FL For the efficiency of the left front wheel motor, η FR For the efficiency of the right front wheel motor, η RL For the efficiency of the left rear wheel motor, η RR For the efficiency of the right rear wheel motor, T demand T represents the total torque required by the vehicle. FL_able T represents the maximum torque of the left front wheel motor. FR_able T represents the maximum torque of the right front wheel motor. RL_able T represents the maximum torque of the left rear wheel motor. RR_able V represents the maximum torque of the right rear wheel motor. oc I is the battery open-circuit voltage. bat For current, r w Where is the wheel radius, μ is the road adhesion coefficient, and F z_FL For the vertical load of the left front wheel motor, F z_FR For the vertical load of the right front wheel motor, F z_RL For the vertical load of the left rear wheel motor, F z_RR For the vertical load of the right rear wheel motor, ΔM z Let yaw moment be denoted by 'a', distance from center of mass to front axle be 'δ', wheel angle be 'B', track width be 'f', and 'a' be 'f'. η_FL (·) represents the efficiency map characteristic of the left front wheel motor, f η_FR (·) represents the efficiency map characteristic of the right front wheel motor, f η_RL (·) represents the efficiency map characteristic of the left rear wheel motor, f η_RR (·) represents the efficiency map characteristic of the right rear wheel motor.

[0093] The final optimization assignment problem in the optimization solution module of S4 is simplified to T FR T RL and T RR For the spatial plane optimization problem of coordinate axes, such as Figure 5 As shown, the optimal three-dimensional spatial coordinates P within the optimization solution space set that satisfies the aforementioned constraints are obtained.best The formula is:

[0094]

[0095] The optimization solution employs an online traversal optimization, which includes the following steps:

[0096] S4-1: T FR and T RL Divide the sample into N and M equal parts at equal intervals, and calculate the T value for each part using relevant formulas. FR and T RL T in combination FR and T RL The relevant formula is:

[0097] T demand =T FL +T FR +T RL +T RR

[0098] D = AT FR +BT RL +CT RR

[0099] Where A, B, C, and D are all constants;

[0100] S4-2: Determine whether each combination satisfies the constraints. If so, calculate P. bat_dem If not, then P bat_dem It is infinitely large;

[0101] S4-3: Repeat steps S4-1 and S4-2 above to obtain an N*M matrix P. bat_dem And determine matrix P bat_dem The row k1 and column k2 of the matrix corresponding to the minimum value are used to obtain the energy-saving torque distribution result of the four-wheel hub motor driven vehicle. The formula is as follows:

[0102]

[0103] In one embodiment of the present invention, the basic parameters of the four-wheel hub motor driven vehicle are: r w =0.32m, SOC b (t0) = 0.9, Q max =100Ah, m=1520kg, g=9.8m / s 2 b = 1.2, l = 2.8, h g =0.53, B=1.452, a x and a yThe variables measured in real time during vehicle movement include the external characteristics of the left front wheel motor, right front wheel motor, left rear wheel motor, and right rear wheel motor, such as... Figure 6 As shown, the motor efficiency map characteristics of the left front wheel motor, right front wheel motor, left rear wheel motor, and right rear wheel motor are as follows: Figure 7 As shown, the internal resistance characteristics of the battery are as follows: Figure 8 As shown, V oc With SOC b The functional relationship of (t), such as Figure 9 As shown.

[0104] This invention proposes an energy-saving torque distribution method for four-wheel hub motor driven vehicles that considers motor failure modes. By taking into account the differences in motor efficiency and optimizing torque distribution according to different failure modes, it achieves more efficient energy utilization, improves vehicle range, enhances the safe operation of four-wheel hub motor driven vehicles, and promotes the development and application of electric vehicle technology.

[0105] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention, and should be understood that the scope of protection of the invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of the invention.

Claims

1. A method for energy-saving torque distribution in a four-wheel hub motor driven vehicle considering motor failure, characterized in that, Includes the following steps: S1: The fault mode identification module obtains the actual output torque of the motor based on the sensor signals of the four-wheel hub motor, and determines the motor fault mode category by combining the motor voltage, current, motor temperature, motor driver temperature and the actual torque required by the motor. S2: Select the fault mode control method according to the motor fault mode category; S3: Based on the selected fault mode control method, the objective function and constraint module are optimized using the energy-saving allocation strategy to perform objective optimization; The objective function and constraint formulas for the energy-saving allocation strategy optimization objective function and constraint module in S3 are as follows: in, This indicates taking the minimum value. For battery output power, This refers to the torque of the left front wheel motor. This refers to the torque of the right front wheel motor. This refers to the torque of the left rear wheel motor. This refers to the torque of the right rear wheel motor. For rotational speed, For the efficiency of the left front wheel motor, For the efficiency of the right front wheel motor, For the efficiency of the left rear wheel motor, For the efficiency of the right rear wheel motor, This is the total torque required by the vehicle. This represents the maximum torque of the left front wheel motor. This represents the maximum torque of the right front wheel motor. This represents the maximum torque of the left rear wheel motor. This represents the maximum torque of the right rear wheel motor. This is the battery open-circuit voltage. For current, For the wheel radius, The road surface adhesion coefficient, The vertical load is for the left front wheel motor. The vertical load is for the right front wheel motor. The vertical load is for the left rear wheel motor. The vertical load is for the right rear wheel motor. For yaw moment, This is the distance from the center of gravity to the front axle. For the turning angle of the wheel, The wheelbase is the distance between the wheels. The efficiency map characteristics of the left front wheel motor. The efficiency map characteristics of the right front wheel motor. The efficiency map characteristics of the left rear wheel motor. Efficiency map characteristics of the right rear wheel motor; S4: Based on the optimization results, the energy-saving torque distribution results of the four-wheel hub motor driven vehicle are obtained using the optimization solution module, and the energy-saving torque distribution of the four-wheel hub motor driven vehicle considering motor failure is completed.

2. The energy-saving torque distribution method for a four-wheel hub motor driven vehicle considering motor failure, as described in claim 1, is characterized in that... The motor fault mode categories in S2 include normal mode, complete failure mode, and performance limitation mode. The complete failure modes include single motor failure, same-side dual motor failure, opposite-side coaxial dual motor failure, opposite-side opposite-axis dual motor failure, three-motor failure, and four-motor failure. The performance limiting modes include speed or torque limitation for single motor failure, speed or torque limitation for dual motor failure on the same side, speed or torque limitation for dual motor failure on opposite sides and coaxial sides, speed or torque limitation for dual motor failure on opposite sides and opposite axes, speed or torque limitation for three motor failures, and speed or torque limitation for four motor failures.

3. The energy-saving torque distribution method for four-wheel hub motor driven vehicles considering motor failure, as described in claim 2, is characterized in that... The control method for the normal mode is as follows: control is performed according to the normal control state, the torque of the four motors is the maximum torque of the motors, and the target optimization is performed in the energy-saving allocation strategy optimization objective function and constraint module. The control method for single motor failure is as follows: perform normal driving to achieve straight-line driving, and then enter the energy-saving allocation strategy optimization objective function and constraint module for objective optimization; The control method for the same-side dual-motor fault is as follows: if there is a deviation, control is performed in conjunction with steering, and energy-saving allocation is performed on the two normal motors, and the objective function and constraint module for energy-saving allocation strategy optimization are entered for objective optimization. The control methods for the faults of the coaxial dual motors on the opposite side and the dual motors on the opposite side are as follows: normal drive, additional yaw torque is achieved through differential torque distribution, and the target is optimized by entering the energy-saving distribution strategy optimization objective function and constraint module. The control method for the three-motor fault is: low-speed limp driving, without entering the energy-saving allocation strategy optimization objective function and constraint module; The control method for the four-motor fault is as follows: stop the vehicle and enter the energy-saving allocation strategy optimization objective function and constraint module for objective optimization; The control method for the performance limitation mode is as follows: torque distribution optimization is performed within the limited speed and torque range, and the target optimization is performed by entering the energy-saving distribution strategy optimization objective function and constraint module.

4. The energy-saving torque distribution method for four-wheel hub motor driven vehicles considering motor failure, as described in claim 3, is characterized in that... The final optimization allocation problem in the optimization solution module of S4 is simplified to: , and This is a spatial plane optimization problem for coordinate axes, aiming to find the optimal three-dimensional spatial coordinates within the solution space set that satisfies the aforementioned constraints. The formula is: 。 5. The energy-saving torque distribution method for a four-wheel hub motor driven vehicle considering motor failure, as described in claim 4, is characterized in that... The optimization solution employs online traversal optimization, including the following steps: S4-1: Will and Divide into equal intervals Shares and Each portion is calculated using relevant formulas. and Combination and The relevant formula is: in, , , and All are constants; S4-2: Determine whether each combination satisfies the stated constraints. If so, calculate... If not, then It is infinitely large; S4-3: Repeat steps S4-1 and S4-2 above to obtain... matrix And determine the matrix The row of the matrix corresponding to the minimum value and column The formula for obtaining the energy-saving torque distribution result of a four-wheel hub motor driven vehicle is as follows: 。

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