A distributed electric vehicle yaw stability control system

Abstract

This invention discloses a distributed yaw stability control system for electric vehicles, comprising an information acquisition module, an evaluation calculation module, a reference value calculation module, a vehicle-wide additional yaw moment calculation module, a vehicle-wide longitudinal force calculation module, and a torque distribution module. The information acquisition module acquires first-type, second-type, and third-type parameters; the evaluation calculation module calculates evaluation factors for the first-type, second-type, and third-type parameters, as well as an evaluation factor for the operating condition; the reference value calculation module calculates reference values ​​for the center of gravity sideslip angle and yaw rate; the vehicle-wide additional yaw moment calculation module calculates the vehicle-wide additional yaw moment; the vehicle-wide longitudinal force calculation module sets a reference vehicle speed and calculates the desired total longitudinal force of the vehicle; and the torque distribution module calculates the desired torque for each wheel to achieve stability control.

Description

Technical Field

[0001] This invention relates to the field of active safety control technology for vehicles, and in particular to a distributed yaw stability control system for electric vehicles. Background Technology

[0002] Distributed drive electric vehicles based on hub motors can effectively reduce emissions and achieve higher energy efficiency, thus helping to alleviate energy shortages and environmental pollution. Because hub motors are independently controllable, have high transmission efficiency, and offer precise and rapid torque response, distributed drive electric vehicles based on hub motors are more likely to achieve high-performance, advanced vehicle dynamics control. By rationally controlling each hub motor, distributed drive electric vehicles based on hub motors can achieve superior driving stability and safety compared to traditional vehicles. Yaw stability control can track the ideal yaw rate while suppressing the increase in the center of gravity sideslip angle, reducing the occurrence of vehicle instability. It can also correct instability promptly, returning the vehicle from the unstable region to the stable region. However, existing yaw stability control methods have poor robustness to changing operating conditions and do not comprehensively consider the vehicle's lateral and longitudinal motion as well as road conditions. Therefore, how to comprehensively consider the vehicle's lateral and longitudinal motion as well as road conditions to improve the robustness of yaw stability control methods to changing operating conditions urgently needs to be addressed. To this end, this invention proposes a distributed electric vehicle yaw stability control system. Summary of the Invention

[0003] The purpose of this invention is to provide a distributed electric vehicle yaw stability control system to solve the problems encountered in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: A distributed electric vehicle yaw stability control system, comprising an information acquisition module, an evaluation calculation module, a reference value calculation module, a vehicle additional yaw moment calculation module, a vehicle longitudinal force calculation module, and a torque distribution module.

[0005] The information acquisition module is used to acquire the first type of parameters, the second type of parameters, and the third type of parameters;

[0006] The first type of parameter includes the vehicle's longitudinal speed. longitudinal acceleration of vehicles and the wheel speed of each wheel of the vehicle These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0007] The second type of parameter includes vehicle lateral speed. Front wheel steering angle of the vehicle lateral acceleration of the vehicle Vehicle center of gravity sideslip angle Vehicle yaw rate and vehicle load transfer rate ;

[0008] The third type of parameter includes the longitudinal slope of the road surface where the vehicle is located. The curvature of the road surface where the vehicle is located Lateral slope of the road surface where the vehicle is located The road surface adhesion coefficient of the vehicle ;

[0009] The evaluation calculation module is used to calculate the evaluation factor of the first type of parameter based on the first type of parameter. Calculate the evaluation factor of the second type of parameter based on the second type of parameter. Calculate the evaluation factor of the third type of parameter based on the third type of parameter. ;

[0010] First type of parameter evaluation factor As shown in the following formula:

[0011] ,

[0012] Second type of parameter evaluation factor As shown in the following formula:

[0013] ,

[0014] The third type of parameter evaluation factor As shown in the following formula:

[0015] ,

[0016] First type of parameter evaluation factor The second type of parameter evaluation factor is used to reflect the longitudinal motion of the vehicle. The third type of parameter evaluation factor is used to reflect the lateral movement of the vehicle. Used to reflect the current road conditions where the vehicle is located;

[0017] The evaluation calculation module is used to evaluate factors based on the first type of parameters. Second type of parameter evaluation factor and the third type of parameter evaluation factor Calculate the operating condition evaluation factor ;

[0018] The working condition evaluation factor It is used to comprehensively reflect the current road conditions and the vehicle's movement.

[0019] The reference value calculation module is used to calculate the vehicle longitudinal speed based on the first type of parameters. The second type of parameter is the vehicle's front wheel steering angle. And the road surface adhesion coefficient of the road surface where the vehicle is located in the third type of parameter. Calculate the reference value of the centroid sideslip angle and yaw rate reference value ;

[0020] The vehicle additional yaw moment calculation module is used to calculate the center of gravity sideslip angle reference value. yaw rate reference value The longitudinal speed of the vehicle in the first type of parameter The vehicle's front wheel steering angle in the second type of parameter Establish the system steady-state equation, error model, prediction equation, performance function, and constraints; perform quadratic programming to solve the problem; and calculate the additional yaw moment of the entire vehicle. ;

[0021] The vehicle longitudinal force calculation module is used to set a reference vehicle speed. Based on the vehicle longitudinal speed in the first type of parameter and the set reference speed Calculate the expected total longitudinal force of the whole vehicle ;

[0022] The torque distribution module is used to determine the state evaluation factor. Determine and select the additional yaw moment of the whole vehicle. And the expected total longitudinal force of the whole vehicle The torque distribution mode is used to calculate the desired torque for each wheel to achieve stability control. These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0023] The evaluation factor of the first type of parameter is calculated based on the first type of parameter. Specifically, it includes:

[0024] The evaluation factor for the first type of parameter can be calculated using the following formula. :

[0025] ,

[0026] In the formula, These are weighting coefficients. .

[0027] The second type of parameter evaluation factor is calculated based on the second type of parameter. Specifically, it includes:

[0028] The evaluation factor for the second type of parameter can be calculated using the following formula. :

[0029] ,

[0030] In the formula, These are weighting coefficients. .

[0031] The evaluation factor of the third type of parameter is calculated based on the third type of parameter. Specifically, it includes:

[0032] The evaluation factor for the third type of parameter can be calculated using the following formula. :

[0033] ,

[0034] In the formula, These are weighting coefficients. .

[0035] The evaluation factor based on the first type of parameter Second type of parameter evaluation factor and the third type of parameter evaluation factor Calculate the operating condition evaluation factor Specifically, it includes:

[0036] ,

[0037] In the formula, Evaluation factors of the first type of parameter Corresponding operating condition evaluation factors Calculate the weighted values. Second type of parameter evaluation factor Corresponding operating condition evaluation factors Calculate the weighted values. Evaluation factors for the third type of parameters Corresponding operating condition evaluation factors Calculate the weighted values. .

[0038] The reference value calculation module is used to calculate the vehicle longitudinal speed based on the first type of parameters. The second type of parameter is the vehicle's front wheel steering angle. And the road surface adhesion coefficient of the road surface where the vehicle is located in the third type of parameter. Calculate the reference value of the centroid sideslip angle and yaw rate reference value Specifically, it includes:

[0039] Reference value of centroid side slip angle for:

[0040] ,

[0041] Yaw velocity reference value for:

[0042] ,

[0043] In the formula, This indicates the distance from the front axle to the center of gravity of the vehicle. This indicates the distance from the rear axle to the center of gravity of the vehicle. As a stability factor, Indicates wheelbase. Indicates vehicle mass. These are the front and rear axle lateral stiffness, respectively. It represents the acceleration due to gravity.

[0044] The vehicle additional yaw moment calculation module specifically includes:

[0045] The steady-state equation calculation unit is used to calculate the centroid sideslip angle reference value. yaw rate reference value The longitudinal speed of the vehicle in the first type of parameter The vehicle's front wheel steering angle in the second type of parameter And from the two-degree-of-freedom model of the car to the system steady-state equation:

[0046] ,

[0047] In the formula, , , Indicates vehicles go around Moment of inertia of the shaft;

[0048] The error model calculation unit is used to calculate the state variable as the centroid sideslip angle error. and yaw rate error The controlled quantity is the additional yaw moment of the entire vehicle. Error model:

[0049] ,

[0050] In the formula, , This indicates the additional yaw moment of the entire vehicle;

[0051] The prediction equation calculation unit is used to discretize the error model to obtain the prediction equation.

[0052] ,

[0053] In the formula: , Sampling time, At the current sampling time, The next sampling time;

[0054] The performance function and constraint construction unit is used to construct the performance function and constraint conditions for the optimization problem based on the state variables, control variables, and control variable constraints.

[0055] The performance function expression is as follows:

[0056] ,

[0057] In the formula, These are the prediction step size and the control step size, respectively. for Time prediction The state quantity at any given time. for Time prediction The amount of control at any given moment and These represent the weighting coefficient matrices for system state variables and control variables, respectively.

[0058] The constraint condition is the controller output value, i.e., the value of the additional yaw moment of the whole vehicle, expressed as:

[0059] ,

[0060] In the formula: These represent the controller outputs. The minimum and maximum values;

[0061] The quadratic programming solver unit transforms the above optimization problem into a quadratic programming problem and solves it to obtain the additional yaw moment of the entire vehicle. .

[0062] The torque distribution module specifically includes:

[0063] Distribution mode selection unit and torque distribution unit;

[0064] The allocation mode selection unit is used to select the operating condition evaluation factor. Select the distribution mode of the torque distribution unit; the torque distribution unit includes three levels of distribution modes: first-level torque distribution mode, second-level torque distribution mode, and third-level torque distribution mode; control factor of the first-level torque distribution mode of the distribution mode selection unit is designed. Second-level torque distribution mode Third-level torque distribution mode control factor This is to enable switching between allocation modes, where When the working condition evaluation factor Between When the distribution mode selection unit selects the first-level torque distribution mode for the torque distribution unit; when the operating condition evaluation factor... Between When the distribution mode selection unit selects the torque distribution unit's distribution mode as the second-level torque distribution mode; when the operating condition evaluation factor... Between When the torque distribution mode selection unit selects the third-level torque distribution mode, the distribution mode of the torque distribution unit is selected.

[0065] The torque distribution unit is used to determine the distribution mode of the torque distribution unit selected by the distribution mode selection unit, as well as the additional yaw moment of the vehicle. And the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0066] The torque distribution unit specifically includes:

[0067] The first-level torque distribution mode is used when the distribution mode selection unit selects the first-level torque distribution mode, based on the vehicle's additional yaw moment. And the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0068] Among them, the expected torque of each wheel for:

[0069] ,

[0070] In the formula, These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. Indicates the effective radius of the wheel. Indicates wheel track;

[0071] The second-level torque distribution mode is used when the distribution mode selection unit selects the second-level torque distribution mode, based on the vehicle's additional yaw moment. And the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0072] Among them, the expected torque of each wheel for:

[0073] ,

[0074] In the formula: Indicates the height of the vehicle's center of gravity. This indicates the vehicle's longitudinal acceleration;

[0075] The third-level torque distribution mode is used when the distribution mode selection unit selects the third-level torque distribution mode, based on the vehicle's additional yaw moment. And the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0076] Among them, the expected longitudinal force of each wheel This can be obtained by solving the following quadratic programming optimization problem:

[0077] ,

[0078] In the formula: The objective function represents the optimization problem. These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. This represents the utilization rate weighting coefficient for each wheel. This indicates the vertical load on each wheel;

[0079] The desired torque for each wheel can then be obtained using the following formula. :

[0080] ,

[0081] In the formula: Indicates the effective radius of the tire.

[0082] The utilization rate weighting coefficient of each wheel Specifically, it includes:

[0083] The utilization rate weighting coefficients for the left front wheel and the right front wheel are respectively ;

[0084] The utilization rate weighting coefficients for the right and left rear wheels can be calculated using the following formula. :

[0085] ,

[0086] In the formula, This represents the yaw rate error.

[0087] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0088] The present invention provides a distributed electric vehicle yaw stability control system, which can acquire first-type parameters, second-type parameters and third-type parameters through an information acquisition module; calculate evaluation factors of the first-type parameters to reflect the longitudinal motion of the vehicle, calculate evaluation factors of the second-type parameters to reflect the lateral motion of the vehicle, calculate evaluation factors of the third-type parameters to reflect the current road surface conditions of the vehicle, and calculate operating condition evaluation factors to comprehensively reflect the current road surface conditions and the motion of the vehicle.

[0089] The torque distribution module of the present invention includes a distribution mode selection unit and a torque distribution unit. The torque distribution unit includes three levels of torque distribution modes: a first-level torque distribution mode, a second-level torque distribution mode, and a third-level torque distribution mode. The switching selection of the distribution mode is realized by designing the first-level torque distribution mode control factor, the second-level torque distribution mode control factor, and the third-level torque distribution mode control factor of the distribution mode selection unit.

[0090] The torque distribution module determines and selects the additional yaw moment of the whole vehicle based on the state evaluation factors. And the expected total longitudinal force of the whole vehicle The torque distribution mode is used to calculate the desired torque for each wheel to achieve stability control. Attached Figure Description

[0091] The present invention will be further described below with reference to the accompanying drawings:

[0092] Figure 1 This invention presents a distributed electric vehicle yaw stability control system. Detailed Implementation

[0093] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0094] like Figure 1 As shown, the present invention is a distributed electric vehicle yaw stability control system, including an information acquisition module, an evaluation calculation module, a reference value calculation module, a vehicle additional yaw moment calculation module, a vehicle longitudinal force calculation module, and a torque distribution module.

[0095] The information acquisition module is used to acquire the first type of parameters, the second type of parameters, and the third type of parameters;

[0096] The first type of parameter includes the vehicle's longitudinal speed. longitudinal acceleration of vehicles and the wheel speed of each wheel of the vehicle These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0097] The second type of parameter includes vehicle lateral speed. Front wheel steering angle of the vehicle lateral acceleration of the vehicle Vehicle center of gravity sideslip angle Vehicle yaw rate and vehicle load transfer rate ;

[0098] The third type of parameter includes the longitudinal slope of the road surface where the vehicle is located. The curvature of the road surface where the vehicle is located Lateral slope of the road surface where the vehicle is located The road surface adhesion coefficient of the vehicle ;

[0099] The evaluation calculation module is used to calculate the evaluation factor of the first type of parameter based on the first type of parameter. Calculate the evaluation factor of the second type of parameter based on the second type of parameter. Calculate the evaluation factor of the third type of parameter based on the third type of parameter. ;

[0100] First type of parameter evaluation factor As shown in the following formula:

[0101] ,

[0102] Second type of parameter evaluation factor As shown in the following formula:

[0103] ,

[0104] The third type of parameter evaluation factor As shown in the following formula:

[0105] ,

[0106] First type of parameter evaluation factor The second type of parameter evaluation factor is used to reflect the longitudinal motion of the vehicle. The third type of parameter evaluation factor is used to reflect the lateral movement of the vehicle. Used to reflect the current road conditions where the vehicle is located;

[0107] The evaluation calculation module is used to evaluate factors based on the first type of parameters. Second type of parameter evaluation factor and the third type of parameter evaluation factor Calculate the operating condition evaluation factor ;

[0108] The working condition evaluation factor It is used to comprehensively reflect the current road conditions and the vehicle's movement.

[0109] The reference value calculation module is used to calculate the vehicle longitudinal speed based on the first type of parameters. The second type of parameter is the vehicle's front wheel steering angle. And the road surface adhesion coefficient of the road surface where the vehicle is located in the third type of parameter. Calculate the reference value of the centroid sideslip angle and yaw rate reference value ;

[0110] The vehicle additional yaw moment calculation module is used to calculate the center of gravity sideslip angle reference value. yaw rate reference value The longitudinal speed of the vehicle in the first type of parameter The vehicle's front wheel steering angle in the second type of parameter Establish the system steady-state equation, error model, prediction equation, performance function, and constraints; perform quadratic programming to solve the problem; and calculate the additional yaw moment of the entire vehicle. ;

[0111] The vehicle longitudinal force calculation module is used to set a reference vehicle speed. Based on the vehicle longitudinal speed in the first type of parameter and the set reference speed Calculate the expected total longitudinal force of the whole vehicle ;

[0112] The torque distribution module is used to determine the state evaluation factor. Determine and select the additional yaw moment of the whole vehicle. And the expected total longitudinal force of the whole vehicle The torque distribution mode is used to calculate the desired torque for each wheel to achieve stability control. These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0113] The evaluation factor of the first type of parameter is calculated based on the first type of parameter. Specifically, it includes:

[0114] The evaluation factor for the first type of parameter can be calculated using the following formula. :

[0115] ,

[0116] In the formula, These are weighting coefficients. .

[0117] The second type of parameter evaluation factor is calculated based on the second type of parameter. Specifically, it includes:

[0118] The evaluation factor for the second type of parameter can be calculated using the following formula. :

[0119] ,

[0120] In the formula, These are weighting coefficients. .

[0121] The evaluation factor of the third type of parameter is calculated based on the third type of parameter. Specifically, it includes:

[0122] The evaluation factor for the third type of parameter can be calculated using the following formula. :

[0123] ,

[0124] In the formula, These are weighting coefficients. .

[0125] The evaluation factor based on the first type of parameter Second type of parameter evaluation factor and the third type of parameter evaluation factor Calculate the operating condition evaluation factor Specifically, it includes:

[0126] ,

[0127] In the formula, Evaluation factors of the first type of parameter Corresponding operating condition evaluation factors Calculate the weighted values. Second type of parameter evaluation factor Corresponding operating condition evaluation factors Calculate the weighted values. Evaluation factors for the third type of parameters Corresponding operating condition evaluation factors Calculate the weighted values. .

[0128] The reference value calculation module is used to calculate the vehicle longitudinal speed based on the first type of parameters. The second type of parameter is the vehicle's front wheel steering angle. And the road surface adhesion coefficient of the road surface where the vehicle is located in the third type of parameter. Calculate the reference value of the centroid sideslip angle and yaw rate reference value Specifically, it includes:

[0129] Reference value of centroid side slip angle for:

[0130] ,

[0131] Yaw velocity reference value for:

[0132] ,

[0133] In the formula, This indicates the distance from the front axle to the center of gravity of the vehicle. This indicates the distance from the rear axle to the center of gravity of the vehicle. As a stability factor, Indicates wheelbase. Indicates vehicle mass. These are the front and rear axle lateral stiffness, respectively. It represents the acceleration due to gravity.

[0134] The vehicle additional yaw moment calculation module specifically includes:

[0135] The steady-state equation calculation unit is used to calculate the centroid sideslip angle reference value. yaw rate reference value The longitudinal speed of the vehicle in the first type of parameter The vehicle's front wheel steering angle in the second type of parameter And from the two-degree-of-freedom model of the car to the system steady-state equation:

[0136] ,

[0137] In the formula, , , Indicates vehicles go around Moment of inertia of the shaft;

[0138] The error model calculation unit is used to calculate the state variable as the centroid sideslip angle error. and yaw rate error The controlled quantity is the additional yaw moment of the entire vehicle. Error model:

[0139] ,

[0140] In the formula, , This indicates the additional yaw moment of the entire vehicle;

[0141] The prediction equation calculation unit is used to discretize the error model to obtain the prediction equation.

[0142] ,

[0143] In the formula: , Sampling time, At the current sampling time, The next sampling time;

[0144] The performance function and constraint construction unit is used to construct the performance function and constraint conditions for the optimization problem based on the state variables, control variables, and control variable constraints.

[0145] The performance function expression is as follows:

[0146] ,

[0147] In the formula, These are the prediction step size and the control step size, respectively. for Time prediction The state quantity at any given time. for Time prediction The amount of control at any given moment and These represent the weighting coefficient matrices for system state variables and control variables, respectively.

[0148] The constraint condition is the controller output value, i.e., the value of the additional yaw moment of the whole vehicle, expressed as:

[0149] ,

[0150] In the formula: These represent the controller outputs. The minimum and maximum values;

[0151] The quadratic programming solver unit transforms the above optimization problem into a quadratic programming problem and solves it to obtain the additional yaw moment of the entire vehicle. .

[0152] The torque distribution module specifically includes:

[0153] Distribution mode selection unit and torque distribution unit;

[0154] The allocation mode selection unit is used to select the operating condition evaluation factor. Select the distribution mode of the torque distribution unit; the torque distribution unit includes three levels of distribution modes: first-level torque distribution mode, second-level torque distribution mode, and third-level torque distribution mode; control factor of the first-level torque distribution mode of the distribution mode selection unit is designed. Second-level torque distribution mode Third-level torque distribution mode control factor This is to enable switching between allocation modes, where When the working condition evaluation factor Between When the distribution mode selection unit selects the first-level torque distribution mode for the torque distribution unit; when the operating condition evaluation factor... Between When the distribution mode selection unit selects the torque distribution unit's distribution mode as the second-level torque distribution mode; when the operating condition evaluation factor... Between When the torque distribution mode selection unit selects the third-level torque distribution mode, the distribution mode of the torque distribution unit is selected.

[0155] The torque distribution unit is used to determine the distribution mode of the torque distribution unit selected by the distribution mode selection unit, as well as the additional yaw moment of the vehicle. And the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0156] The torque distribution unit specifically includes:

[0157] The first-level torque distribution mode is used when the distribution mode selection unit selects the first-level torque distribution mode, based on the vehicle's additional yaw moment. And the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0158] Among them, the expected torque of each wheel for:

[0159] ,

[0160] In the formula, These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. Indicates the effective radius of the wheel. Indicates wheel track;

[0161] The second-level torque distribution mode is used when the distribution mode selection unit selects the second-level torque distribution mode, based on the vehicle's additional yaw moment. And the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0162] Among them, the expected torque of each wheel for:

[0163] ,

[0164] In the formula: Indicates the height of the vehicle's center of gravity. This indicates the vehicle's longitudinal acceleration;

[0165] The third-level torque distribution mode is used when the distribution mode selection unit selects the third-level torque distribution mode, based on the vehicle's additional yaw moment. And the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

[0166] Among them, the expected longitudinal force of each wheel This can be obtained by solving the following quadratic programming optimization problem:

[0167] ,

[0168] In the formula: The objective function represents the optimization problem. These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. This represents the utilization rate weighting coefficient for each wheel. This indicates the vertical load on each wheel;

[0169] The desired torque for each wheel can then be obtained using the following formula. :

[0170] ,

[0171] In the formula: Indicates the effective radius of the tire.

[0172] The utilization rate weighting coefficient of each wheel Specifically, it includes:

[0173] The utilization rate weighting coefficients for the left front wheel and the right front wheel are respectively ;

[0174] The utilization rate weighting coefficients for the right and left rear wheels can be calculated using the following formula. :

[0175] ,

[0176] In the formula, This represents the yaw rate error.

Claims

1. A distributed electric vehicle yaw stability control system, characterized in that, Includes the following: It includes an information acquisition module, an evaluation calculation module, a reference value calculation module, a vehicle additional yaw moment calculation module, a vehicle longitudinal force calculation module, and a torque distribution module; The information acquisition module is used to acquire the first type of parameters, the second type of parameters, and the third type of parameters; The first type of parameter includes the vehicle's longitudinal speed. longitudinal acceleration of vehicles and the wheel speed of each wheel of the vehicle These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. The second type of parameter includes vehicle lateral speed. Front wheel steering angle of the vehicle lateral acceleration of the vehicle Vehicle center of gravity sideslip angle Vehicle yaw rate and vehicle load transfer rate ; The third type of parameter includes the longitudinal slope of the road surface where the vehicle is located. The curvature of the road surface where the vehicle is located Lateral slope of the road surface where the vehicle is located The road surface adhesion coefficient of the vehicle ; The evaluation calculation module is used to calculate the evaluation factor of the first type of parameter based on the first type of parameter. Calculate the evaluation factor of the second type of parameter based on the second type of parameter. Calculate the evaluation factor of the third type of parameter based on the third type of parameter. ; First type of parameter evaluation factor As shown in the following formula: ， Second type of parameter evaluation factor As shown in the following formula: ， The third type of parameter evaluation factor As shown in the following formula: ， First type of parameter evaluation factor The second type of parameter evaluation factor is used to reflect the longitudinal motion of the vehicle. The third type of parameter evaluation factor is used to reflect the lateral movement of the vehicle. Used to reflect the current road conditions where the vehicle is located; The evaluation calculation module is used to evaluate factors based on the first type of parameters. Second type of parameter evaluation factor and the third type of parameter evaluation factor Calculate the operating condition evaluation factor ; The working condition evaluation factor It is used to comprehensively reflect the current road conditions and the vehicle's movement. The reference value calculation module is used to calculate the vehicle longitudinal speed based on the first type of parameters. The second type of parameter is the vehicle's front wheel steering angle. And the road surface adhesion coefficient of the road surface where the vehicle is located in the third type of parameter. Calculate the reference value of the centroid sideslip angle and yaw rate reference value ; The vehicle additional yaw moment calculation module is used to calculate the center of gravity sideslip angle reference value. yaw rate reference value The longitudinal speed of the vehicle in the first type of parameter The vehicle's front wheel steering angle in the second type of parameter Establish the system steady-state equation, error model, prediction equation, performance function, and constraints; perform quadratic programming to solve the problem; and calculate the additional yaw moment of the entire vehicle. ; The vehicle longitudinal force calculation module is used to set a reference vehicle speed. Based on the vehicle longitudinal speed in the first type of parameter and the set reference speed Calculate the expected total longitudinal force of the whole vehicle ; The torque distribution module is used to determine the state evaluation factor. Determine and select the additional yaw moment of the whole vehicle. and the expected total longitudinal force of the whole vehicle The torque distribution mode is used to calculate the desired torque for each wheel to achieve stability control. These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

2. The distributed electric vehicle yaw stability control system according to claim 1, characterized in that, The evaluation factor of the first type of parameter is calculated based on the first type of parameter. Specifically, it includes: The evaluation factor for the first type of parameter can be calculated using the following formula. : ， In the formula, These are weighting coefficients. .

3. The distributed electric vehicle yaw stability control system according to claim 1, characterized in that, The second type of parameter evaluation factor is calculated based on the second type of parameter. Specifically, it includes: The evaluation factor for the second type of parameter can be calculated using the following formula. : ， In the formula, These are weighting coefficients. .

4. A distributed electric vehicle yaw stability control system according to claim 1, characterized in that, The evaluation factor of the third type of parameter is calculated based on the third type of parameter. Specifically, it includes: The evaluation factor for the third type of parameter can be calculated using the following formula. : ， In the formula, These are weighting coefficients. .

5. A distributed electric vehicle yaw stability control system according to claim 1, characterized in that, The evaluation factor based on the first type of parameter Second type of parameter evaluation factor and the third type of parameter evaluation factor Calculate the operating condition evaluation factor Specifically, it includes: ， In the formula, Evaluation factors of the first type of parameter Corresponding operating condition evaluation factors Calculate the weighted values. Second type of parameter evaluation factor Corresponding operating condition evaluation factors Calculate the weighted values. Evaluation factors for the third type of parameters Corresponding operating condition evaluation factors Calculate the weighted values. .

6. A distributed electric vehicle yaw stability control system according to claim 1, characterized in that, The reference value calculation module is used to calculate the vehicle longitudinal speed based on the first type of parameters. The second type of parameter is the vehicle's front wheel steering angle. And the road surface adhesion coefficient of the road surface where the vehicle is located in the third type of parameter. Calculate the reference value of the centroid sideslip angle and yaw rate reference value Specifically, it includes: Reference value of centroid side slip angle for: ， Yaw velocity reference value for: ， In the formula, This indicates the distance from the front axle to the center of gravity of the vehicle. This indicates the distance from the rear axle to the center of gravity of the vehicle. As a stability factor, Indicates wheelbase. Indicates vehicle mass. These are the front and rear axle lateral stiffness, respectively. It represents the acceleration due to gravity.

7. A distributed electric vehicle yaw stability control system according to claim 1, characterized in that, The vehicle additional yaw moment calculation module specifically includes: The steady-state equation calculation unit is used to calculate the centroid sideslip angle reference value. yaw rate reference value The longitudinal speed of the vehicle in the first type of parameter The vehicle's front wheel steering angle in the second type of parameter And from the two-degree-of-freedom model of the car to the system steady-state equation: ， In the formula, , , Indicates vehicles go around Moment of inertia of the shaft; This indicates the distance from the front axle to the center of gravity of the vehicle. This indicates the distance from the rear axle to the center of gravity of the vehicle. Indicates vehicle mass. These are the front and rear axle lateral stiffness, respectively. The error model calculation unit is used to calculate the state variable as the centroid sideslip angle error. and yaw rate error The controlled quantity is the additional yaw moment of the entire vehicle. Error model: ， In the formula, , This indicates the additional yaw moment of the entire vehicle; The prediction equation calculation unit is used to discretize the error model to obtain the prediction equation. ， In the formula: , Sampling time, At the current sampling time, The next sampling time; The performance function and constraint construction unit is used to construct the performance function and constraint conditions for the optimization problem based on the state variables, control variables, and control variable constraints. The performance function expression is as follows: ， In the formula, These are the prediction step size and the control step size, respectively. for Time prediction The state quantity at any given time. for Time prediction The amount of control at any given moment and These represent the weighting coefficient matrices for system state variables and control variables, respectively. The constraint condition is the controller output value, i.e., the value of the additional yaw moment of the whole vehicle, expressed as: ， In the formula: These represent the controller outputs. The minimum and maximum values; The quadratic programming solver unit transforms the above optimization problem into a quadratic programming problem and solves it to obtain the additional yaw moment of the entire vehicle. .

8. A distributed electric vehicle yaw stability control system according to claim 1, characterized in that, The torque distribution module specifically includes: Distribution mode selection unit and torque distribution unit; The allocation mode selection unit is used to select the operating condition evaluation factor. Select the distribution mode of the torque distribution unit; the torque distribution unit includes three levels of distribution modes: first-level torque distribution mode, second-level torque distribution mode, and third-level torque distribution mode; control factor of the first-level torque distribution mode of the distribution mode selection unit is designed. Second-level torque distribution mode Third-level torque distribution mode control factor This is to enable switching between allocation modes, where When the working condition evaluation factor Between When the distribution mode selection unit selects the first-level torque distribution mode for the torque distribution unit; when the operating condition evaluation factor... Between When the distribution mode selection unit selects the torque distribution unit's distribution mode as the second-level torque distribution mode; when the operating condition evaluation factor... Between When the torque distribution mode selection unit selects the third-level torque distribution mode, the distribution mode of the torque distribution unit is selected. The torque distribution unit is used to determine the distribution mode of the torque distribution unit selected by the distribution mode selection unit, as well as the additional yaw moment of the vehicle. and the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively.

9. A distributed electric vehicle yaw stability control system according to claim 8, characterized in that, The torque distribution unit specifically includes: The first-level torque distribution mode is used when the distribution mode selection unit selects the first-level torque distribution mode, based on the vehicle's additional yaw moment. and the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. Among them, the expected torque of each wheel for: ， In the formula, These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. Indicates the effective radius of the wheel. Indicates wheel track; The second-level torque distribution mode is used when the distribution mode selection unit selects the second-level torque distribution mode, based on the vehicle's additional yaw moment. and the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. Among them, the expected torque of each wheel for: ， In the formula: Indicates the height of the vehicle's center of gravity. This represents the longitudinal acceleration of the vehicle. Represents gravitational acceleration. This indicates the distance from the front axle to the center of gravity of the vehicle. This indicates the distance from the rear axle to the center of gravity of the vehicle. Indicates wheelbase; The third-level torque distribution mode is used when the distribution mode selection unit selects the third-level torque distribution mode, based on the vehicle's additional yaw moment. and the expected total longitudinal force of the whole vehicle Calculate the desired torque for each wheel These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. Among them, the expected longitudinal force of each wheel This can be obtained by solving the following quadratic programming optimization problem: ， In the formula: The objective function represents the optimization problem. These represent the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. This represents the utilization rate weighting coefficient for each wheel. This indicates the vertical load on each wheel; The desired torque for each wheel can then be obtained using the following formula. : ， In the formula: Indicates the effective radius of the tire.

10. A distributed electric vehicle yaw stability control system according to claim 9, characterized in that, The utilization rate weighting coefficient of each wheel Specifically, it includes: The utilization rate weighting coefficients for the left front wheel and the right front wheel are respectively ; The utilization rate weighting coefficients for the right and left rear wheels can be calculated using the following formula. : , In the formula, This represents the yaw rate error.

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