Vehicle electric drive system control method

Abstract

The application provides a vehicle electric drive system control method, which comprises the following steps: shooting and analyzing a road state image of a current driving road of a vehicle to determine whether the vehicle is currently driving on a slope; determining driving resistance information of each wheel according to vehicle pose information and ground resistance information of the vehicle during slope driving, and determining driving force required for driving each wheel along a preset vehicle driving path in combination with the preset vehicle driving path, and then determining torque information of an electric motor connected with each wheel for applying to the corresponding wheel, so as to adjust the electric drive mode of the electric motor, so that the electric motor can drive each wheel to drive and steer independently, thereby ensuring that the vehicle can stably drive on the slope and avoiding the situation that the vehicle slips or overturns during slope driving, and improving the safety of the vehicle during slope driving.

Description

Technical Field

[0001] This invention relates to the technical field of electric vehicle control, and particularly to a method for controlling a vehicle's electric drive system. Background Technology

[0002] Electric vehicles move by directly driving the wheels with an electric motor. The resistance an electric vehicle experiences on flat ground and on a slope differs, requiring the electric motor to apply different driving modes and torques to the wheels for each terrain. Particularly when driving on a slope, the vehicle is in an inclined position, and the resistance experienced by the wheels differs significantly from that on flat ground. To ensure smooth driving on slopes, each wheel needs to be driven independently to prevent slippage or sideslip. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a vehicle electric drive system control method. This method involves capturing and analyzing images of the road conditions the vehicle is currently traveling on to determine if it is on a slope. Based on the vehicle's position and ground resistance information during slope travel, the method determines the driving resistance information experienced by each wheel. Combined with a preset vehicle travel path, the method determines the driving force required to drive each wheel along that path. Subsequently, it determines the torque information applied to the corresponding wheel by the electric motor connected to each wheel, thereby adjusting the electric drive mode of the motor. This allows the motor to drive each wheel individually for steering, ensuring smooth vehicle travel on slopes and preventing skidding or rollover, thus improving vehicle safety on slopes.

[0004] This invention provides a control method for a vehicle electric drive system, which includes the following steps:

[0005] Step S1: Acquire road condition images of the vehicle's current driving route, analyze the road condition images to determine whether the vehicle is currently driving on a slope; and acquire vehicle pose information and ground resistance information during the vehicle's driving on the slope.

[0006] Step S2: Based on the vehicle position information and the ground resistance information, determine the driving resistance information of each wheel of the vehicle; based on the driving resistance information and the preset vehicle driving path, determine the driving force required to drive each wheel along the preset vehicle driving path.

[0007] Step S3: Based on the driving force, determine the torque information applied to the corresponding wheel by the motor connected to each wheel drive; and based on the torque information, adjust the electric drive mode of the motor so that the motor applies the corresponding torque to the corresponding wheel.

[0008] Furthermore, in step S1, acquiring road condition images of the vehicle's current travel, analyzing the road condition images to determine whether the vehicle is currently traveling on a slope; and acquiring vehicle pose information and ground resistance information during the slope travel process specifically includes:

[0009] Step S101: Take a binocular picture of the road surface in front of the vehicle during the current driving process to obtain a road surface condition image; perform noise reduction preprocessing and pixel preprocessing on the road surface condition image; extract pixel contour distribution information from the road surface condition image; determine the height change gradient value of the road surface based on the pixel contour distribution information.

[0010] Step S102: Determine whether the road surface the vehicle is currently traveling on is a slope based on the magnitude of the height change gradient value;

[0011] Step S103: Collect the vehicle's front-end position information and the rolling friction resistance information between each wheel of the vehicle and the ground during the vehicle's driving on the slope.

[0012] Further, in step S101, the road condition image undergoes noise reduction preprocessing and pixel preprocessing; then, pixel contour distribution information is extracted from the road condition image; and based on the pixel contour distribution information, the determination of the road surface height change gradient value specifically includes:

[0013] After performing Kalman filtering and pixel sharpening on the road condition image in sequence, pixel contour distribution information is extracted from the road condition image; the distance between two adjacent pixel contour lines in the road condition image is determined based on the pixel contour distribution information; and the height change gradient value of the road surface is determined based on the distance between two adjacent pixel contour lines.

[0014] Furthermore, in step S102, determining whether the road surface the vehicle is currently traveling on is a slope based on the magnitude of the height change gradient value specifically includes:

[0015] The height change gradient value is compared with a preset gradient value range. If the height change gradient value is within the preset gradient value range, it is determined that the road surface the vehicle is currently traveling on is not a slope; otherwise, it is determined that the road surface the vehicle is currently traveling on is a slope.

[0016] Further, in step S2, based on the vehicle pose information and the ground resistance information, the driving resistance information experienced by each wheel of the vehicle is determined; based on the driving resistance information and the preset vehicle driving path, the driving force required to drive each wheel along the preset vehicle driving path is determined, specifically including:

[0017] Step S201: Based on the vehicle front pose information and the rolling friction resistance information of each wheel, determine the driving resistance value of each wheel in the pitch angle direction, yaw angle direction and roll angle direction.

[0018] Step S202: Based on the driving resistance value, determine the actual driving path of the vehicle under the current driving resistance, and then determine the path offset between the actual driving path and the preset vehicle driving path.

[0019] Step S203: Determine the driving force required to drive each wheel along the preset vehicle driving path based on the path offset and the vehicle's current driving speed.

[0020] Further, in step S201, based on the vehicle's front-end orientation information and the rolling friction resistance information of each wheel, determining the driving resistance value experienced by each wheel in the pitch, yaw, and roll directions specifically includes:

[0021] Using the formula (1) below, based on the vehicle's front-end orientation information and the rolling friction resistance information of each wheel, the driving resistance values ​​experienced by each wheel in the pitch, yaw, and roll directions are obtained.

[0022]

[0023] In the above formula (1), This represents the drag force experienced by the a-th wheel of the vehicle in the pitch direction; This represents the drag force experienced by the a-th wheel of the vehicle in the yaw angle direction; This represents the rolling resistance value experienced by the a-th wheel of the vehicle in the direction of the roll angle; This represents the rolling friction resistance of the a-th wheel of the vehicle; Indicates the direction in which the front of the vehicle is moving; Indicates the direction the vehicle is currently heading towards its destination; The angle between the pitch direction and the vehicle's forward direction is called the pitch angle. This represents the angle between the direction of the rolling friction resistance of the a-th wheel of the vehicle and the direction of the vehicle's forward movement; X0 represents the angle between the direction the vehicle is heading towards its destination and the direction the vehicle is moving forward; Y0 represents the pitch angle in the vehicle's pose information in the direction the vehicle is moving forward; Y0 represents the pitch angle in the vehicle's pose information perpendicular to the direction the vehicle is moving forward.

[0024] In step S202, determining the actual driving path of the vehicle under the current driving resistance based on the driving resistance value, and then determining the path offset between the actual driving path and the preset vehicle driving path specifically includes:

[0025] Using formula (2) below, the actual travel path of the vehicle under the current travel resistance value is determined.

[0026]

[0027] In the above formula (2), S represents the actual driving path length of the vehicle under the current driving resistance; L represents the preset driving path length of the vehicle. This indicates calculating the sum of the vectors within the parentheses; m represents the number of wheels on the vehicle, with a value of 4.

[0028] The path offset between the actual driving path and the preset vehicle driving path is LS;

[0029] In step S3, determining the driving force required to drive each wheel along the preset vehicle travel path based on the path offset and the vehicle's current speed specifically includes:

[0030] Using the formula (3) below, the driving force required to drive each wheel along the preset vehicle travel path is determined based on the path offset and the vehicle's current speed.

[0031]

[0032] In the above formula (3), F(a) represents the driving force required for the a-th wheel of the vehicle to travel along the preset vehicle travel path; M represents the mass of the vehicle; || represents the calculation of the modulus; V represents the current driving speed of the vehicle;

[0033] Further, in step S3, determining the torque information applied to the corresponding wheel by the motor connected to each wheel drive based on the driving force; and adjusting the electric drive mode of the motor based on the torque information, so that the motor applies the corresponding torque to the corresponding wheel, specifically includes:

[0034] Step S301: Based on the driving force and the relative positional relationship between each wheel and its connected motor, determine the torque applied to the corresponding wheel by the motor connected to each wheel.

[0035] Step S302: Adjust the rotor position of the motor according to the torque to change the electric drive mode of the motor, so that the motor applies a matching torque to the corresponding wheel.

[0036] Further, in step S301, determining the torque applied to the corresponding wheel by the motor connected to each wheel based on the driving force and the relative positional relationship between each wheel and its connected motor specifically includes:

[0037] Based on the driving force and the distance between each wheel and its connected motor, the torque applied by the motor connected to each wheel to the corresponding wheel is determined.

[0038] Furthermore, in step S302, adjusting the rotor position of the electric motor according to the torque to change the electric drive mode of the electric motor, thereby allowing the electric motor to apply a matching torque to the corresponding wheel, specifically includes:

[0039] Based on the torque, the position of the motor rotor relative to the motor stator is adjusted to change the electric drive mode of the motor, thereby causing the motor to apply a matching braking torque to the corresponding wheel.

[0040] Compared to existing technologies, this vehicle electric drive system control method determines whether the vehicle is currently traveling on a slope by capturing and analyzing images of the road conditions. Based on the vehicle's position and ground resistance information during slope travel, it determines the driving resistance information of each wheel and, combined with a preset vehicle travel path, determines the driving force required to drive each wheel along that path. It then determines the torque information applied to the corresponding wheel by the electric motor connected to each wheel, thereby adjusting the electric drive mode of the motor. This allows the motor to drive each wheel individually for steering, ensuring smooth vehicle travel on slopes and preventing skidding or rollover, thus improving vehicle safety on slopes.

[0041] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0042] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a flowchart illustrating the vehicle electric drive system control method provided by the present invention. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] See Figure 1 This is a flowchart illustrating a vehicle electric drive system control method provided in an embodiment of the present invention. The vehicle electric drive system control method includes the following steps:

[0047] Step S1: Acquire road condition images of the vehicle's current driving route, analyze the road condition images to determine whether the vehicle is currently driving on a slope; and acquire vehicle pose information and ground resistance information during the vehicle's driving on the slope.

[0048] Step S2: Based on the vehicle pose information and the ground resistance information, determine the driving resistance information of each wheel of the vehicle; based on the driving resistance information and the preset vehicle driving path, determine the driving force required to drive each wheel along the preset vehicle driving path.

[0049] Step S3: Based on the driving force, determine the torque information applied to the corresponding wheel by the motor connected to each wheel drive; and based on the torque information, adjust the electric drive mode of the motor so that the motor applies the corresponding torque to the corresponding wheel.

[0050] The beneficial effects of the above technical solution are as follows: The vehicle electric drive system control method determines whether the vehicle is currently driving on a slope by capturing and analyzing images of the road conditions the vehicle is currently traveling on; based on the vehicle's position and posture information and ground resistance information during the slope driving process, it determines the driving resistance information of each wheel, and combined with the preset vehicle driving path, it determines the driving force required to drive each wheel along the preset vehicle driving path, and then determines the torque information applied to the corresponding wheel by the motor connected to each wheel, thereby adjusting the electric drive mode of the motor so that the motor can drive each wheel to drive and steer independently, thereby ensuring that the vehicle can drive smoothly on the slope and avoiding the vehicle from slipping or overturning during the slope driving process, thus improving the safety of the vehicle driving on the slope.

[0051] Preferably, in step S1, acquiring road condition images of the vehicle's current travel, analyzing these images to determine whether the vehicle is currently traveling on a slope; and acquiring vehicle pose information and ground resistance information during the slope travel process specifically includes:

[0052] Step S101: Take a binocular picture of the road surface in front of the vehicle during the current driving process to obtain a road condition image of the road surface; perform noise reduction preprocessing and pixel preprocessing on the road condition image; extract pixel contour distribution information from the road condition image; determine the height change gradient value of the road surface based on the pixel contour distribution information.

[0053] Step S102: Determine whether the road surface the vehicle is currently traveling on is a slope based on the magnitude of the height change gradient value;

[0054] Step S103: Collect the vehicle's front-end position information and the rolling friction resistance information between each wheel of the vehicle and the ground during the vehicle's driving on the slope.

[0055] The beneficial effects of the above technical solution are as follows: During vehicle operation, a binocular camera located at the front of the vehicle captures images of the road surface ahead, enabling real-time acquisition of images of the road surface as the vehicle travels. When the vehicle is traveling on flat ground and on a slope, the binocular images captured by the camera show significant differences in pixel contour distribution. For example, the pixel contour distribution of the binocular image corresponding to a flat road surface is much smoother than that of the binocular image corresponding to a slope. Extracting the corresponding pixel contour distribution information from the road state image after noise reduction and pixel preprocessing allows for the determination of the road surface height gradient value, facilitating accurate subsequent judgment of whether the road surface is a slope. Furthermore, the vehicle's front-end pose information can be detected by a gyroscope or three-axis accelerometer located at the front of the vehicle, and the rolling friction resistance information between each wheel and the ground can be detected by friction sensors located on each wheel.

[0056] Preferably, in step S101, the road condition image undergoes noise reduction preprocessing and pixel preprocessing; then, pixel contour distribution information is extracted from the road condition image; and based on the pixel contour distribution information, the determination of the road surface height change gradient value specifically includes:

[0057] After performing Kalman filtering and pixel sharpening on the road condition image, pixel contour distribution information is extracted from the road condition image. The distance between adjacent pixel contour lines in the road condition image is determined based on the pixel contour distribution information. Then, the height change gradient value of the road surface is determined based on the distance between adjacent pixel contour lines.

[0058] The beneficial effects of the above technical solution are as follows: sequentially performing Kalman filtering and pixel sharpening processing on the road condition image can effectively reduce pixel noise, thereby improving the extraction accuracy of pixel distribution information. Furthermore, when the distance between the contour lines of adjacent pixels in the road condition image is determined, the gradient value of the road surface height change can be determined by performing a corresponding triangular projection transformation on this distance. This process is a conventional image processing method in this field and will not be elaborated upon here.

[0059] Preferably, in step S102, determining whether the road surface the vehicle is currently traveling on is a slope based on the magnitude of the height change gradient value specifically includes:

[0060] The height change gradient value is compared with a preset gradient value range. If the height change gradient value is within the preset gradient value range, it is determined that the road surface the vehicle is currently traveling on is not a slope; otherwise, it is determined that the road surface the vehicle is currently traveling on is a slope.

[0061] The beneficial effects of the above technical solution are as follows: Generally speaking, the gradient value of the height change of a sloping road surface is larger than that of a flat road surface. By comparing the gradient value of the height change with the preset gradient value range, it is possible to quantitatively and accurately determine whether the road surface on which the vehicle is currently traveling is a slope.

[0062] Preferably, in step S2, the driving resistance information of each wheel of the vehicle is determined based on the vehicle pose information and the ground resistance information; the driving force required to drive each wheel along the preset vehicle driving path is determined based on the driving resistance information and the preset vehicle driving path, specifically including:

[0063] Step S201: Based on the vehicle's front-end orientation information and the rolling friction resistance information of each wheel, determine the driving resistance value of each wheel in the pitch angle direction, yaw angle direction, and roll angle direction.

[0064] Step S202: Based on the driving resistance value, determine the actual driving path of the vehicle under the current driving resistance, and then determine the path offset between the actual driving path and the preset vehicle driving path.

[0065] Step S203: Based on the path offset and the vehicle's current speed, determine the driving force required to drive each wheel along the preset vehicle travel path.

[0066] The beneficial effects of the above technical solution are as follows: When a vehicle is driving on a slope, the position and resistance of different wheels of the vehicle are not the same. By determining the driving resistance value of each wheel in the pitch angle direction, yaw angle direction and roll angle direction, the path offset of the vehicle on the slope can be determined. This makes it easier to determine the driving force required to adjust each wheel to the preset vehicle driving path, thereby facilitating the motor to provide individual and targeted driving action for each wheel.

[0067] Preferably, in step S201, determining the driving resistance values ​​experienced by each wheel in the pitch, yaw, and roll directions based on the vehicle's front-end orientation information and the rolling friction resistance information of each wheel specifically includes:

[0068] Using the formula (1) below, based on the vehicle's front-end orientation information and the rolling friction resistance information of each wheel, the driving resistance values ​​experienced by each wheel in the pitch, yaw, and roll directions are obtained.

[0069]

[0070] In the above formula (1), This represents the drag force experienced by the a-th wheel of the vehicle in the pitch direction; This represents the drag force experienced by the a-th wheel of the vehicle in the yaw angle direction; This represents the rolling resistance value experienced by the a-th wheel of the vehicle in the direction of the roll angle; This represents the rolling friction resistance of the a-th wheel of the vehicle; Indicates the direction in which the front of the vehicle is moving; Indicates the direction the vehicle is currently heading towards its destination; The angle between the pitch direction and the vehicle's forward direction is called the pitch angle. This represents the angle between the direction of the rolling friction resistance of the a-th wheel of the vehicle and the direction of the vehicle's forward movement; X0 represents the angle between the direction the vehicle is heading towards its destination and the direction the vehicle is moving forward; Y0 represents the pitch angle in the direction the vehicle is moving forward in the vehicle's pose information; Y0 represents the pitch angle in the direction the vehicle is moving forward perpendicular to the vehicle's pose information.

[0071] In step S202, based on the driving resistance value, the actual driving path of the vehicle under the current driving resistance is determined, and the path offset between the actual driving path and the preset vehicle driving path is determined, specifically including:

[0072] Using formula (2) below, the actual travel path of the vehicle under the current travel resistance value is determined.

[0073]

[0074] In the above formula (2), S represents the actual driving path length of the vehicle under the current driving resistance; L represents the preset driving path length of the vehicle. This indicates calculating the sum of the vectors within the parentheses; m represents the number of wheels on the vehicle, with a value of 4.

[0075] The path offset between the actual driving path and the preset vehicle driving path is LS;

[0076] In step S3, based on the path offset and the vehicle's current speed, the driving force required to drive each wheel along the preset vehicle travel path is determined, specifically including:

[0077] Using the formula (3) below, the driving force required to drive each wheel along the preset vehicle travel path is determined based on the path offset and the vehicle's current speed.

[0078]

[0079] In the above formula (3), F(a) represents the driving force required for the a-th wheel of the vehicle to travel along the preset vehicle travel path; M represents the mass of the vehicle; || represents the calculation of the modulus; and V represents the current driving speed of the vehicle.

[0080] The beneficial effects of the above technical solution are as follows: Using the above formula (1), based on the vehicle's front position information and the rolling friction resistance information of each wheel, the driving resistance value of each wheel in the pitch angle direction, yaw angle direction and roll angle direction can be obtained, and the resistance situation of the vehicle can be analyzed from multiple angles; then, using the above formula (2), based on the driving resistance value, the actual driving path of the vehicle under the current driving resistance can be determined, and the actual driving state and path of the vehicle can be analyzed, which is convenient for subsequent analysis and control of driving force; finally, using the above formula (3), based on the path offset and the current driving speed of the vehicle, the driving force required to drive each wheel along the preset vehicle driving path can be determined, and the driving force of each wheel can be controlled to ensure that the vehicle can reach the destination smoothly.

[0081] Preferably, in step S3, determining the torque information applied to the corresponding wheel by the motor connected to each wheel drive based on the driving force; and adjusting the electric drive mode of the motor based on the torque information, so that the motor applies the corresponding torque to the corresponding wheel, specifically includes:

[0082] Step S301: Based on the driving force and the relative positional relationship between each wheel and its connected motor, determine the torque applied to the corresponding wheel by the motor connected to each wheel.

[0083] Step S302: Based on the torque, adjust the rotor position of the motor to change the electric drive mode of the motor, thereby enabling the motor to apply a matching torque to the corresponding wheel.

[0084] The beneficial effects of the above technical solution are as follows: each wheel in the vehicle is equipped with a dedicated electric motor, so that each wheel is driven independently, thereby ensuring that the torque applied by the electric motor to the wheel can adjust the speed and steering of the wheel, so as to quickly and steadily correct the overall driving path of the vehicle.

[0085] Preferably, in step S301, determining the torque applied to the corresponding wheel by the motor connected to each wheel based on the driving force and the relative positional relationship between each wheel and its connected motor specifically includes:

[0086] Based on the driving force and the distance between each wheel and its connected motor, the torque applied to the corresponding wheel by the motor connected to each wheel is determined.

[0087] The beneficial effect of the above technical solution is that the product of the driving force and the distance between each wheel and the electric motor connected to it can be used as the torque applied by the electric motor to the corresponding wheel, which can provide a reliable basis for subsequent adjustment of the electric drive mode of the electric motor.

[0088] Preferably, in step S302, adjusting the rotor position of the electric motor according to the torque to change the electric drive mode of the electric motor, thereby allowing the motor to apply a matching torque to the corresponding wheel, specifically includes:

[0089] Based on this torque, the position of the motor rotor relative to the motor stator is adjusted, thereby changing the electric drive mode of the motor, so that the motor applies a matching braking torque to the corresponding wheel.

[0090] The beneficial effects of the above technical solution are as follows: by adjusting the position of the motor rotor relative to the motor stator, the magnitude and direction of the motor output force can be changed, so that the braking torque ultimately output by the motor to the wheel is the same as the torque determined above, so that the vehicle as a whole can quickly travel along the preset vehicle travel path and effectively avoid the vehicle from skidding and overturning.

[0091] As can be seen from the above embodiments, the vehicle electric drive system control method determines whether the vehicle is currently driving on a slope by capturing and analyzing images of the road conditions the vehicle is currently traveling on; based on the vehicle's position and posture information and ground resistance information during the slope driving process, it determines the driving resistance information of each wheel, and combines this with a preset vehicle driving path to determine the driving force required to drive each wheel along the preset vehicle driving path, and then determines the torque information applied to the corresponding wheel by the motor connected to each wheel, thereby adjusting the electric drive mode of the motor so that the motor can drive each wheel to drive and steer independently, thereby ensuring that the vehicle can drive smoothly on the slope and avoiding the vehicle slipping or overturning during the slope driving process, thus improving the safety of the vehicle driving on the slope.

[0092] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A control method for a vehicle electric drive system, characterized in that, It includes the following steps: Step S1: Acquire road condition images of the vehicle's current driving route, analyze the road condition images to determine whether the vehicle is currently driving on a slope; and acquire vehicle pose information and ground resistance information during the vehicle's driving on the slope. Step S2: Based on the vehicle pose information and the ground resistance information, determine the driving resistance information of each wheel of the vehicle. Based on the driving resistance information and the preset vehicle driving path, determine the driving force required to drive each wheel along the preset vehicle driving path; Step S3: Based on the driving force, determine the torque information applied to the corresponding wheel by the motor connected to each wheel drive; and based on the torque information, adjust the electric drive mode of the motor so that the motor applies the corresponding torque to the corresponding wheel. Specifically, in step S3, determining the torque information applied to the corresponding wheel by the motor connected to each wheel drive based on the driving force, and adjusting the electric drive mode of the motor based on the torque information, so that the motor applies the corresponding torque to the corresponding wheel, includes: Step S301: Based on the driving force and the relative positional relationship between each wheel and its connected motor, determine the torque applied to the corresponding wheel by the motor connected to each wheel. Step S302: Adjust the rotor position of the electric motor according to the torque, thereby changing the electric drive mode of the electric motor, so that the electric motor applies a matching torque to the corresponding wheel.

2. The vehicle electric drive system control method as described in claim 1, characterized in that: In step S1, the road condition image of the vehicle's current driving is acquired, and the road condition image is analyzed to determine whether the vehicle is currently driving on a slope. The system collects vehicle position and attitude information and ground resistance information during the vehicle's journey on the slope, specifically including: Step S101: Take a binocular picture of the road surface in front of the vehicle during the current driving process to obtain a road surface condition image; perform noise reduction preprocessing and pixel preprocessing on the road surface condition image; extract pixel contour distribution information from the road surface condition image; determine the height change gradient value of the road surface based on the pixel contour distribution information. Step S102: Determine whether the road surface the vehicle is currently traveling on is a slope based on the magnitude of the height change gradient value; Step S103: Collect the vehicle's front-end position information and the rolling friction resistance information between each wheel of the vehicle and the ground during the vehicle's driving on the slope.

3. The vehicle electric drive system control method as described in claim 2, characterized in that: In step S101, the road condition image undergoes noise reduction preprocessing and pixel preprocessing; then, pixel contour distribution information is extracted from the road condition image; and based on the pixel contour distribution information, the height change gradient value of the road surface is determined, specifically including: After performing Kalman filtering and pixel sharpening on the road condition image in sequence, pixel contour distribution information is extracted from the road condition image; the distance between adjacent pixel contour lines in the road condition image is determined based on the pixel contour distribution information; and the height change gradient value of the road surface is determined based on the distance between adjacent pixel contour lines.

4. The vehicle electric drive system control method as described in claim 3, characterized in that: In step S102, determining whether the road surface the vehicle is currently traveling on is a slope based on the magnitude of the height change gradient value specifically includes: The height change gradient value is compared with a preset gradient value range. If the height change gradient value is within the preset gradient value range, it is determined that the road surface the vehicle is currently traveling on is not a slope; otherwise, it is determined that the road surface the vehicle is currently traveling on is a slope.

5. The vehicle electric drive system control method as described in claim 4, characterized in that: In step S2, the driving resistance information of each wheel of the vehicle is determined based on the vehicle pose information and the ground resistance information. Based on the driving resistance information and the preset vehicle driving path, the driving force required to drive each wheel along the preset vehicle driving path is specifically determined as follows: Step S201: Based on the vehicle front pose information and the rolling friction resistance information of each wheel, determine the driving resistance value of each wheel in the pitch angle direction, yaw angle direction and roll angle direction. Step S202: Based on the driving resistance value, determine the actual driving path of the vehicle under the current driving resistance, and then determine the path offset between the actual driving path and the preset vehicle driving path. Step S203: Based on the path offset and the vehicle's current speed, determine the driving force required to drive each wheel along the preset vehicle travel path.

6. The vehicle electric drive system control method as described in claim 5, characterized in that: In step S201, based on the vehicle's front-end orientation information and the rolling friction resistance information of each wheel, the determination of the driving resistance values ​​experienced by each wheel in the pitch, yaw, and roll directions specifically includes: Using the formula (1) below, based on the vehicle's front-end orientation information and the rolling friction resistance information of each wheel, the driving resistance values ​​experienced by each wheel in the pitch, yaw, and roll directions are obtained. （1） In the above formula (1), Indicates the vehicle's number The driving resistance value experienced by each wheel in the pitch direction; Indicates the vehicle's number The driving resistance value experienced by each wheel in the yaw angle direction; Indicates the vehicle's number The rolling resistance value experienced by each wheel in the direction of the roll angle; Indicates the vehicle's number The rolling friction resistance of each wheel; Indicates the direction in which the front of the vehicle is moving; Indicates the direction the vehicle is currently heading towards its destination; The angle between the pitch direction and the vehicle's forward direction is called the pitch angle. ; Indicates the vehicle's number The angle between the direction of the rolling friction resistance of each wheel and the direction of the vehicle's forward movement. It indicates the angle between the direction the vehicle is heading towards its destination and the direction the vehicle is moving in. This represents the pitch angle of the vehicle's front end in the forward direction of the vehicle's pose information. This refers to the pitch angle in the vehicle's pose information, which is perpendicular to the forward direction of the vehicle's front. In step S202, determining the actual driving path of the vehicle under the current driving resistance based on the driving resistance value, and then determining the path offset between the actual driving path and the preset vehicle driving path specifically includes: Using the formula (2) below, the actual driving path of the vehicle under the current driving resistance value is determined. （2） In the above formula (2), This indicates the actual distance the vehicle travels under the current driving resistance. Indicates the preset vehicle travel path length; [] indicates calculating the sum of the vectors within the brackets; This indicates the number of wheels on the vehicle, and its value is 4. The path offset between the actual driving path and the preset vehicle driving path is: ; In step S3, determining the driving force required to drive each wheel along the preset vehicle travel path based on the path offset and the vehicle's current speed specifically includes: Using the formula (3) below, based on the path offset and the vehicle's current speed, determine the driving force required to drive each wheel along the preset vehicle travel path. （3） In the above formula (3), Indicates the vehicle's number The driving force required for each wheel to travel along the preset vehicle path; Indicates the mass of the vehicle; This indicates the operation of determining the modulus. This indicates the vehicle's current speed.

7. The vehicle electric drive system control method as described in claim 1, characterized in that: In step S301, determining the torque applied to the corresponding wheel by the motor connected to each wheel based on the driving force and the relative positional relationship between each wheel and its connected motor specifically includes: Based on the driving force and the distance between each wheel and its connected motor, the torque applied to the corresponding wheel by the motor connected to each wheel is determined.

8. The vehicle electric drive system control method as described in claim 7, characterized in that: In step S302, adjusting the rotor position of the electric motor according to the torque to change the electric drive mode of the electric motor, thereby allowing the electric motor to apply a matching torque to the corresponding wheel, specifically includes: Based on the torque, the position of the motor rotor relative to the motor stator is adjusted to change the electric drive mode of the motor, thereby causing the motor to apply a matching braking torque to the corresponding wheel.

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