Vehicle stability control method and device on low-adhesion road and new energy vehicle

Abstract

The present application provides a method, device, and new energy vehicle for controlling vehicle stability on low-adhesion roads. The method includes: judging whether the wheel acceleration anti-skid flag is activated based on wheel acceleration and wheel acceleration change rate; determining the wheel acceleration anti-skid target attenuation coefficient when the wheel acceleration anti-skid flag is activated; judging whether the slip rate anti-skid flag is activated based on the wheel slip rate and slip rate threshold; determining the slip rate anti-skid target attenuation coefficient when the slip rate anti-skid flag is activated; when the wheel acceleration anti-skid flag or the slip rate anti-skid flag is activated, processing the requested attenuation coefficient of the current cycle using the attenuation coefficient change gradient; calculating the shaft end requested torque based on the shaft end target torque and the requested attenuation coefficient after gradient processing, and transmitting the shaft end requested torque to the drive motor to perform torque control. The present application improves the stability and passability of the vehicle on low-adhesion roads and enhances the user's driving experience.

Description

Technical Field

[0001] The present application relates to the technical field of new energy vehicles, and in particular to a method and device for controlling vehicle stability on low-adhesion roads, and a new energy vehicle. Background Art

[0002] With the continuous advancement of new energy vehicle technology, improving driving comfort and performance while ensuring safety has become a key issue in the industry. Ensuring vehicle stability is crucial for driver safety and driving experience, especially in complex road conditions. During actual driving, vehicles may encounter low-adhesion surfaces such as wet, icy, or dusty roads. These conditions can reduce the friction coefficient between the vehicle's tires and the road, thereby affecting vehicle stability and safety.

[0003] Traditional solutions rely primarily on hardware technology, such as increasing the friction coefficient between the tires and the road by using higher-friction tires, switching to winter tires in rainy or snowy conditions, or using snow chains. However, these traditional methods are not ideal for new energy vehicles (NEVs) because their powertrains, weight distribution, and control strategies differ from those of traditional vehicles. Consequently, traditional solutions may be inapplicable or have limited effectiveness in NEVs. Therefore, there is an urgent need for a stability control solution for NEVs on low-adhesion roads to address the issues of poor vehicle stability, reduced driving safety, and a poor driving experience when driving on low-adhesion surfaces. Summary of the Invention

[0004] In view of this, the embodiments of the present application provide a method, device and new energy vehicle for controlling vehicle stability on low-adhesion roads to solve the problems existing in the prior art of poor vehicle stability, reduced driving safety and poor driving experience when a car is driving on a low-adhesion road.

[0005] In a first aspect, an embodiment of the present application provides a method for controlling vehicle stability on a low-adhesion road surface, comprising: determining wheel accelerations and wheel acceleration change rates corresponding to each wheel, and determining whether a wheel acceleration anti-skid flag is activated based on the wheel accelerations and wheel acceleration change rates; when the wheel acceleration anti-skid flag is activated, determining a wheel acceleration anti-skid target attenuation coefficient based on the absolute values of the wheel accelerations and the absolute values of the wheel acceleration change rates; determining a slip rate corresponding to each wheel, and determining whether the slip rate anti-skid flag is activated based on the slip rate and a preset slip rate threshold; when the slip rate anti-skid flag is activated, determining a slip rate anti-skid target attenuation coefficient based on the absolute value of the slip rate and the absolute value of the slip rate change rate; when the wheel acceleration anti-skid flag or the slip rate anti-skid flag is activated, determining an attenuation coefficient change gradient, processing a requested attenuation coefficient for a current cycle using the attenuation coefficient change gradient to obtain a gradient-processed requested attenuation coefficient; and calculating a shaft end requested torque based on a shaft end target torque for the current cycle and the gradient-processed requested attenuation coefficient, and transmitting the shaft end requested torque to a drive motor to perform torque control, thereby performing low-adhesion stability control on the vehicle.

[0006] According to a second aspect of an embodiment of the present application, a vehicle stability control device for a low-adhesion road surface is provided, comprising: a first judgment module configured to determine the wheel acceleration and the wheel acceleration change rate corresponding to each wheel, and to judge whether the wheel acceleration anti-skid flag is activated based on the wheel acceleration and the wheel acceleration change rate; a first determination module configured to determine the wheel acceleration anti-skid target attenuation coefficient based on the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate when the wheel acceleration anti-skid flag is activated; a second judgment module configured to determine the slip rate corresponding to each wheel, and to judge whether the slip rate anti-skid flag is activated based on the slip rate and a preset slip rate threshold; and a second determination module configured to determine the slip rate anti-skid flag. The module is configured to determine a slip rate anti-skid target attenuation coefficient based on the absolute value of the slip rate and the absolute value of the slip rate change rate when the slip rate anti-skid flag is activated; the processing module is configured to determine the attenuation coefficient change gradient when the wheel acceleration anti-skid flag or the slip rate anti-skid flag is activated, and use the attenuation coefficient change gradient to process the requested attenuation coefficient of the current cycle to obtain the gradient-processed requested attenuation coefficient; the control module is configured to calculate the shaft end requested torque based on the shaft end target torque of the current cycle and the gradient-processed requested attenuation coefficient, and transmit the shaft end requested torque to the drive motor to perform torque control, so as to perform low-adhesion stability control on the vehicle.

[0007] According to a third aspect of an embodiment of the present application, a new energy vehicle is provided, including a vehicle controller, a motor controller, a drive motor and a transmission system; the vehicle controller is used to implement the steps of the above-mentioned vehicle stability control method on low-adhesion roads to send the shaft end requested torque to the motor controller; the motor controller is used to control the torque of the drive motor through the transmission system according to the shaft end requested torque.

[0008] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects:

[0009] By determining the wheel acceleration and wheel acceleration change rate corresponding to each wheel, based on the wheel acceleration and wheel acceleration change rate, it is determined whether the wheel acceleration anti-skid flag is activated; when the wheel acceleration anti-skid flag is activated, based on the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate, a wheel acceleration anti-skid target attenuation coefficient is determined; the slip rate corresponding to each wheel is determined, and based on the slip rate and a preset slip rate threshold, whether the slip rate anti-skid flag is activated is determined; when the slip rate anti-skid flag is activated, based on the absolute value of the slip rate and the absolute value of the slip rate change rate, a slip rate anti-skid target attenuation coefficient is determined; when the wheel acceleration anti-skid flag or the slip rate anti-skid flag is activated, an attenuation coefficient change gradient is determined, and the attenuation coefficient change gradient is used to process the requested attenuation coefficient of the current cycle to obtain the gradient-processed requested attenuation coefficient; based on the shaft end target torque of the current cycle and the gradient-processed requested attenuation coefficient, the shaft end requested torque is calculated, and the shaft end requested torque is transmitted to the drive motor to perform torque control, so as to perform low-adhesion stability control on the vehicle. This application can accurately identify low-adhesion working conditions and achieve attenuation of the shaft end request torque through the request attenuation coefficient after gradient processing, thereby improving the stability and passability of the vehicle on low-adhesion roads and enhancing the user's driving experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0011] Figure 1 1 is a flow chart of a vehicle stability control method on a low-adhesion road provided by an embodiment of the present application;

[0012] Figure 2 Schematic diagram of the structure of a vehicle stability control device on a low-adhesion road provided by an embodiment of the present application;

[0013] Figure 3 It is a structural diagram of an electronic device provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0014] In the following description, specific details such as specific system structures and techniques are provided for purposes of illustration rather than limitation to facilitate a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obscuring the description of the present application with unnecessary detail.

[0015] It should be understood that the various steps described in the method embodiments of the present application can be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present application is not limited in this respect.

[0016] The term "including" and its variations used in this document are open inclusions, that is, "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". The relevant definitions of other terms will be given in the description below. It should be noted that the concepts of "first", "second", etc. mentioned in this application are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0017] It should be noted that the modifications of "one" and "multiple" mentioned in this application are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly indicated in the context, they should be understood as "one or more".

[0018] The new energy vehicles in the embodiments of this application refer to vehicles that use new energy sources (non-traditional oil and diesel energy) and have advanced technology. These vehicles use new power systems that can effectively reduce vehicle emissions, reduce environmental impact, and improve energy efficiency. The new energy vehicles in the embodiments of this application include but are not limited to the following types of vehicles: electric vehicles (EVs), battery electric vehicles (BEVs), fuel cell electric vehicles (FCEVs), plug-in hybrid electric vehicles (PHEVs), and hybrid electric vehicles (HEVs).

[0019] A method and apparatus for controlling vehicle stability on a low-adhesion road surface according to an embodiment of the present application will be described in detail below with reference to the accompanying drawings.

[0020] Figure 1 It is a flow chart of a vehicle stability control method on a low-adhesion road provided in an embodiment of the present application. Figure 1The vehicle stability control method on low-adhesion roads can be executed by the vehicle controller of the new energy vehicle. Figure 1 As shown, the vehicle stability control method on low-adhesion roads may specifically include:

[0021] S101, determining the wheel acceleration and wheel acceleration change rate corresponding to each wheel, and judging whether the wheel acceleration anti-skid flag is activated based on the wheel acceleration and wheel acceleration change rate;

[0022] S102, when the wheel acceleration anti-skid flag is activated, determining a wheel acceleration anti-skid target attenuation coefficient based on the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate;

[0023] S103, determining the slip rate corresponding to each wheel, and judging whether the slip rate anti-skid flag is activated based on the slip rate and a preset slip rate threshold;

[0024] S104, when the slip rate anti-skid flag is activated, determining a slip rate anti-skid target attenuation coefficient based on the slip rate absolute value and the slip rate change absolute value;

[0025] S105, when the wheel acceleration anti-skid flag or the slip rate anti-skid flag is activated, determining the attenuation coefficient change gradient, and processing the requested attenuation coefficient of the current cycle using the attenuation coefficient change gradient to obtain the gradient-processed requested attenuation coefficient;

[0026] S106 , calculating the shaft end requested torque based on the shaft end target torque of the current cycle and the requested attenuation coefficient after gradient processing, and transmitting the shaft end requested torque to the drive motor to perform torque control, so as to perform low-adhesion stability control on the vehicle.

[0027] In this embodiment of the present application, a vehicle control unit (VCU) is used to monitor the parameters of the vehicle and each wheel in real time during driving to obtain real-time motion parameters. The real-time motion parameters of the vehicle include, but are not limited to, the following parameters: wheel speed, vehicle speed, and target torque at the axle end.

[0028] Furthermore, the embodiments of the present application calculate wheel acceleration and wheel acceleration change rate based on the wheel speed obtained through real-time monitoring. In practical applications, wheel acceleration is the result of a derivative calculation based on the wheel speed, while wheel acceleration change rate is the result of a further derivative calculation based on the wheel acceleration. In one example, the calculation formulas for wheel acceleration and wheel acceleration change rate are respectively:

[0029]

[0030]

[0031] Where V is the wheel speed, a is the wheel acceleration, and μ is the rate of change of the wheel acceleration.

[0032] In some embodiments, determining whether the wheel acceleration anti-skid flag is activated based on the wheel acceleration and the wheel acceleration change rate includes:

[0033] Compare the wheel accelerations and wheel acceleration change rates corresponding to each wheel, and select the maximum wheel acceleration and maximum wheel acceleration change rate;

[0034] When the maximum wheel acceleration is greater than the first wheel acceleration threshold, and the maximum wheel acceleration change rate is greater than the first wheel acceleration change rate threshold, it is determined that the wheel acceleration anti-skid flag is activated;

[0035] When the maximum wheel acceleration is less than the second wheel acceleration threshold and the maximum wheel acceleration change rate is less than the second wheel acceleration change rate threshold within the preset time period, it is determined that the wheel acceleration anti-skid flag is not activated.

[0036] Specifically, the control system of new energy vehicles uses sensing devices to monitor the wheel speed of each wheel in real time and calculates the wheel acceleration based on this information. Furthermore, by continuously monitoring the wheel acceleration, the system can calculate the rate of change of the wheel acceleration. To accurately identify which wheel may be at risk of slipping, the system compares the wheel acceleration and the rate of change of wheel acceleration for each wheel and selects the wheel acceleration and rate of change with the largest value.

[0037] Furthermore, the system calculates the maximum value of the wheel acceleration and wheel acceleration change rate of the left and right wheels. This is done to ensure that the risk of sliding can be accurately captured under any circumstances. The system will then determine whether the wheel acceleration anti-skid flag should be activated based on preset thresholds. These thresholds are based on test scenarios under different adhesion coefficients and are intended to ensure that the system can fully identify the risk of tire instability. In order to enable the system to quickly respond to the risk of sliding and activate the corresponding function in a timely manner, the activation threshold is set to be relatively sensitive. Conversely, to ensure that the function can continue to operate when necessary, the exit threshold is set to be relatively conservative.

[0038] In one example, when the maximum wheel acceleration is greater than the first wheel acceleration threshold and the maximum wheel acceleration rate of change is greater than the first wheel acceleration rate of change threshold, the system determines that the wheel acceleration anti-skid flag has been activated. At this point, the vehicle may be at risk of skidding, and the system needs to take appropriate measures to ensure vehicle stability. Specifically, the wheel acceleration anti-skid flag is activated when the following conditions are met: a > threshold A1, and μ > threshold B1, where a represents the maximum wheel acceleration, μ represents the maximum wheel acceleration rate of change, threshold A1 represents the first wheel acceleration threshold, and threshold B1 represents the first wheel acceleration rate of change threshold.

[0039] In another example, when the system continuously monitors that the maximum wheel acceleration is less than the second wheel acceleration threshold and the maximum wheel acceleration rate of change is less than the second wheel acceleration rate of change threshold for a preset period of time, the system determines that the wheel acceleration anti-skid flag has been deactivated. At this point, the vehicle has regained stability, and the system can cease low-adhesion stability control operations on the vehicle. Specifically, the wheel acceleration anti-skid flag is deactivated when the following conditions are met: a < threshold C1 and remains at Tms, and μ < threshold D1 and remains at Tms, where a represents the maximum wheel acceleration, μ represents the maximum wheel acceleration rate of change, threshold C1 represents the second wheel acceleration threshold, and threshold D1 represents the second wheel acceleration rate of change threshold.

[0040] Through the technical solutions provided by the above embodiments, the present application determines whether the vehicle may be sliding by monitoring the acceleration of the wheels and their rate of change. When it is determined that the vehicle is sliding, the wheel acceleration anti-skid flag is activated. When the vehicle stops sliding, the wheel acceleration anti-skid flag is deactivated, thereby accurately identifying low-attachment conditions and adjusting the vehicle's torque accordingly to ensure stability.

[0041] In some embodiments, determining a wheel acceleration anti-skid target attenuation coefficient based on the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate includes:

[0042] The predetermined first attenuation coefficient mapping relationship is queried using the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate to obtain the wheel acceleration anti-skid target attenuation coefficient; wherein the first attenuation coefficient mapping relationship is used to characterize the preset value of the wheel acceleration anti-skid target attenuation coefficient as the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate change.

[0043] Specifically, when the wheel acceleration anti-skid flag is in the activated state, the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate are used to query the preset wheel acceleration anti-skid attenuation coefficient table (that is, the tabular form of the first attenuation coefficient mapping relationship) to obtain the wheel acceleration anti-skid target attenuation coefficient.

[0044] In one example, an embodiment of the present application can save the first attenuation coefficient mapping relationship in the form of a two-dimensional table, wherein the horizontal axis of the two-dimensional table here (i.e., the wheel acceleration anti-skid attenuation coefficient table) represents the absolute value of the wheel acceleration change rate, the vertical axis represents the absolute value of the wheel acceleration, and the table lookup value is the wheel acceleration anti-skid target attenuation coefficient.

[0045] The following describes the process of determining the target wheel acceleration anti-skid attenuation coefficient by looking up the value in the two-dimensional table in the embodiment of the present application, in conjunction with the wheel acceleration anti-skid attenuation coefficient table involved in the actual application scenario of the embodiment of the present application. As shown in Table 1, Table 1 is the wheel acceleration anti-skid attenuation coefficient table configured in the actual application scenario of the embodiment of the present application.

[0046] Table 1 Wheel acceleration anti-skid attenuation coefficient table

[0047] 0 10 30 0 1 0.9 0.8 10 0.7 0.6 0.5 30 0.5 0.4 0.3

[0048] Given the absolute values of the wheel accelerations and the absolute values of the wheel acceleration rate of change, a unique wheel acceleration anti-skid target attenuation coefficient can be determined by querying Table 1, with the absolute value of the wheel acceleration rate of change as the horizontal axis (corresponding to the horizontal axis in Table 1) and the absolute value of the wheel acceleration as the vertical axis (corresponding to the vertical axis in Table 1). Therefore, the value of the wheel acceleration anti-skid target attenuation coefficient is determined by the absolute values of the wheel accelerations and the absolute values of the wheel acceleration rate of change in the current cycle.

[0049] In some embodiments, the method further comprises:

[0050] Acquiring historical measured data of the vehicle, and setting corresponding wheel acceleration anti-skid target attenuation coefficients for the wheel acceleration absolute values and the wheel acceleration rate absolute values according to historical wheel accelerations and historical wheel acceleration rate changes in the historical measured data, and establishing a first attenuation coefficient mapping relationship between the wheel acceleration anti-skid target attenuation coefficients and the wheel acceleration absolute values and the wheel acceleration rate absolute values;

[0051] The configuration rule of the wheel acceleration anti-skid target attenuation coefficient includes a rule set such that the larger the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate, the smaller the wheel acceleration anti-skid target attenuation coefficient.

[0052] Specifically, the control system acquires historical measured vehicle data, including historical wheel accelerations and historical wheel acceleration rates of change. Based on this historical data, the system uses predefined configuration rules for wheel acceleration anti-skid target attenuation coefficients to analyze the absolute values of the wheel accelerations and the absolute values of the wheel acceleration rates of change, and sets corresponding wheel acceleration anti-skid target attenuation coefficients. Furthermore, a first attenuation coefficient mapping relationship is established between the wheel acceleration anti-skid target attenuation coefficients and the absolute values of the wheel accelerations and the absolute values of the wheel acceleration rates of change.

[0053] In practice, the first attenuation coefficient mapping is based on a core principle: when the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate are larger (indicating more severe tire instability), the system needs to take more drastic measures to restore vehicle stability to more effectively address this situation. Therefore, the wheel acceleration anti-slip target attenuation coefficient is set to a smaller value, which will further attenuate the vehicle's torque output, helping to reduce slip and quickly restore stability.

[0054] To achieve this, the control system uses a predefined configuration rule for the wheel acceleration anti-skid target attenuation coefficient. The basic principle of this rule is that the greater the absolute value of the wheel acceleration and the absolute value of the wheel acceleration rate of change, the smaller the wheel acceleration anti-skid target attenuation coefficient. This configuration ensures that the system can take more forceful measures to restore vehicle stability in the face of more severe slip or instability.

[0055] In some embodiments, determining whether the anti-slip flag is activated based on the sliding rate and a preset sliding rate threshold includes:

[0056] The slip rates corresponding to each wheel are compared, and the maximum slip rate is selected. When the maximum slip rate is greater than the slip rate threshold, it is determined that the slip rate anti-skid flag is activated. When the maximum slip rate is less than the slip rate threshold, it is determined that the slip rate anti-skid flag is not activated.

[0057] Specifically, the vehicle low-adhesion stability control method of this application further incorporates anti-skid control based on slip rate. The control system monitors the slip rate of each wheel in real time. The slip rate is an indicator of the degree of wheel slip relative to the road surface; a higher value indicates greater relative slip between the tire and the road surface. To accurately determine which wheel has the highest slip rate, the system compares the slip rates of each wheel and selects the maximum value.

[0058] In one example, the present embodiment calculates the slip rate of each wheel based on the wheel speed of each wheel and the vehicle speed. The calculation process is as follows:

[0059]

[0060]

[0061] Among them, δ represents the slip rate, V represents the vehicle speed, V w Indicates the wheel speed of each wheel.

[0062] Furthermore, to simplify calculations and improve response speed, the system only analyzes the maximum slip rate of the left and right wheels. This ensures that the system can respond quickly and accurately to any potential risk of slip. The system determines whether the slip rate anti-skid flag should be activated based on preset slip rate thresholds. These thresholds are developed based on test scenarios with different adhesion coefficients and are designed to ensure that the system can accurately identify when the slip rate reaches or exceeds a certain threshold, indicating a potential risk of slipping. To enable the system to respond quickly and activate the corresponding function promptly, the slip rate activation threshold is set relatively low. When the slip rate reaches or slightly exceeds this value, the system determines that the wheel is slipping and activates the anti-skid flag. Conversely, to ensure that the function remains active when necessary, the slip rate exit threshold is set relatively high.

[0063] In one example, when the maximum slip rate exceeds a preset slip rate threshold (i.e., δ > slip rate threshold), the system determines that the slip rate anti-skid flag has been activated. At this point, it is determined that at least one wheel may be at risk of slipping, and the system needs to take appropriate measures to restore vehicle stability.

[0064] In another example, when the maximum slip rate is less than the slip rate threshold (i.e., δ < slip rate threshold), the system will determine that the slip rate anti-skid flag has been exited, indicating that the vehicle has regained stability and the system can stop continuing to perform low-adhesion stability control operations on the vehicle.

[0065] The technical solution provided by the above embodiments provides a slip rate-based stability control method for new energy vehicles, which can respond to various slip risks more accurately and quickly, and take appropriate measures to ensure vehicle stability and driving safety.

[0066] In some embodiments, determining a slip rate anti-skid target attenuation coefficient based on the absolute value of the slip rate and the absolute value of the slip rate change rate includes:

[0067] The absolute value of the slip rate and the absolute value of the slip rate change rate are used to query the predetermined second attenuation coefficient mapping relationship to obtain the slip rate anti-skid target attenuation coefficient; wherein, the second attenuation coefficient mapping relationship is used to characterize the preset value of the slip rate anti-skid target attenuation coefficient that changes with the absolute value of the slip rate and the absolute value of the slip rate change rate.

[0068] Specifically, when the slip rate anti-skid flag is in the activated state, the absolute value of the slip rate and the absolute value of the slip rate change rate are used to query the preset slip rate anti-skid target attenuation coefficient table (that is, the tabular form of the second attenuation coefficient mapping relationship) to obtain the slip rate anti-skid target attenuation coefficient.

[0069] In one example, an embodiment of the present application can save the second attenuation coefficient mapping relationship in the form of a two-dimensional table, wherein the horizontal axis of the two-dimensional table here (i.e., the slip rate anti-skid target attenuation coefficient table) represents the absolute value of the slip rate, the vertical axis represents the absolute value of the slip rate change rate, and the table lookup value is the slip rate anti-skid target attenuation coefficient.

[0070] The following describes the process of determining the sliding rate anti-skid target attenuation coefficient by looking up the value in the two-dimensional table in the embodiment of the present application, in combination with the sliding rate anti-skid target attenuation coefficient table involved in the actual application scenario of the embodiment of the present application, as shown in Table 2. Table 2 is the sliding rate anti-skid target attenuation coefficient table configured in the actual application scenario of the embodiment of the present application.

[0071] Table 2 Slip rate anti-skid target attenuation coefficient table

[0072] 0 10 30 0 0.8 0.7 0.6 10 0.7 0.6 0.5 30 0.5 0.4 0.3

[0073] Given the absolute value of the slip rate and the absolute value of the slip rate change rate, a unique slip rate anti-skid target attenuation coefficient can be determined by querying Table 2, with the absolute value of the slip rate change rate as the horizontal axis (corresponding to the horizontal axis of Table 2) and the absolute value of the slip rate as the vertical axis (corresponding to the vertical axis of Table 2). Therefore, the value of the slip rate anti-skid target attenuation coefficient is determined by the absolute value of the slip rate and the absolute value of the slip rate change rate in the current cycle.

[0074] In some embodiments, the method further comprises:

[0075] Obtaining historical measured data of the vehicle, setting corresponding slip rate anti-skid target attenuation coefficients for the absolute value of the slip rate and the absolute value of the slip rate change rate based on historical slip rates and historical slip rate change rates in the historical measured data, and establishing a second attenuation coefficient mapping relationship between the slip rate anti-skid target attenuation coefficient and the absolute value of the slip rate and the absolute value of the slip rate change rate;

[0076] The configuration rule of the slip rate anti-skid target attenuation coefficient includes a rule set with the goal that the larger the absolute value of the slip rate and the absolute value of the slip rate change rate are, the smaller the slip rate anti-skid target attenuation coefficient is.

[0077] Specifically, the control system retrieves historical measured vehicle data from an onboard database. This data records the vehicle's historical slip rate and slip rate change rate during past driving. Based on this historical data, the control system uses pre-defined rules for configuring the slip rate anti-skid target attenuation coefficient to analyze the absolute value of the slip rate and the absolute value of the slip rate change rate, thereby setting the corresponding slip rate anti-skid target attenuation coefficient. The system then establishes a second attenuation coefficient mapping relationship between the slip rate anti-skid target attenuation coefficient and the absolute values of the slip rate and the absolute values of the slip rate change rate.

[0078] In practice, the second damping coefficient mapping follows a core principle: larger absolute values of the slip rate and the absolute value of the slip rate change indicate more severe tire instability. To more effectively address this situation, the system must take more drastic measures to restore vehicle stability. Therefore, the slip rate anti-skid target damping coefficient is set to a smaller value, further dampening the vehicle's torque output, helping to reduce slip and quickly restore stability.

[0079] Therefore, to achieve this goal, the slip rate anti-skid target attenuation coefficient is configured based on the following principle: the greater the absolute value of the slip rate and the absolute value of the slip rate change rate, the smaller the slip rate anti-skid target attenuation coefficient. This setting ensures that the system can take more forceful measures to restore vehicle stability in the face of more severe slip or instability.

[0080] In some embodiments, before determining the attenuation coefficient change gradient, the method further includes:

[0081] When the wheel acceleration anti-skid flag is activated, or the wheel acceleration anti-skid flag and the slip rate anti-skid flag are both activated, the wheel acceleration anti-skid target attenuation coefficient is used as the target attenuation coefficient;

[0082] When the wheel acceleration anti-skid flag is in the inactive state, the slip rate anti-skid target attenuation coefficient is used as the target attenuation coefficient.

[0083] Specifically, to select an appropriate target damping coefficient and provide a more adaptive stability control strategy for the vehicle, the system first checks the activation status of the wheel acceleration anti-skid flag and the slip rate anti-skid flag before determining the damping coefficient change gradient. The activation status of these two flags provides the system with key information about the vehicle's current stability.

[0084] In one example, if the wheel acceleration anti-skid flag is activated, the system uses the wheel acceleration anti-skid target attenuation factor as the target attenuation factor, regardless of whether the slip rate anti-skid flag is activated. This is because wheel acceleration generally more directly and accurately reflects the real-time state of the wheel. Therefore, when the wheel acceleration anti-skid flag is activated, the system prioritizes wheel acceleration information.

[0085] In another example, if the wheel acceleration anti-skid flag is inactive and the slip rate anti-skid flag is active, the system uses the slip rate anti-skid target attenuation factor as the target attenuation factor. This is because the slip rate can provide the system with useful information about the overall vehicle stability when the wheel acceleration anti-skid flag is inactive.

[0086] In some embodiments, determining the attenuation coefficient change gradient includes:

[0087] Using the vehicle speed and the shaft end target torque in the current cycle, a predetermined attenuation coefficient change gradient mapping relationship is queried to obtain the attenuation coefficient change gradient; the attenuation coefficient change gradient mapping relationship is used to represent a preset value of the attenuation coefficient change gradient as the vehicle speed and the shaft end target torque change;

[0088] Among them, the attenuation coefficient change gradient mapping relationship is to use the predetermined attenuation coefficient change gradient configuration rules to set the corresponding attenuation coefficient change gradient for the vehicle speed and the shaft end target torque, and the attenuation coefficient change gradient mapping relationship is established based on the mapping relationship between the attenuation coefficient change gradient, the vehicle speed and the shaft end target torque; the attenuation coefficient change gradient configuration rules include when the wheel acceleration anti-skid flag or the slip rate anti-skid flag is activated, the rule set for controlling the requested attenuation coefficient of the current cycle to drop to the target.

[0089] Specifically, the system first collects data on the vehicle's speed and shaft-end target torque for the current cycle. These two parameters are key factors in determining the attenuation coefficient gradient, as they are closely related to the vehicle's dynamic performance and stability. The system then uses a predetermined attenuation coefficient gradient mapping relationship to query these two parameters. This mapping relationship is a two-dimensional table, with the shaft-end target torque as the horizontal axis and the vehicle speed as the vertical axis. By querying this table, the system can obtain the preset value of the attenuation coefficient gradient under the current conditions. The purpose of this mapping relationship is to ensure that the system can select the most appropriate attenuation coefficient gradient under different driving conditions, thereby achieving the best stability control effect.

[0090] Furthermore, if the wheel acceleration anti-slip flag or the slip rate anti-slip flag is activated, the system's strategy becomes more conservative. In this case, the system controls the requested damping coefficient for the current cycle to decrease only. This is because when a wheel is slipping, vehicle stability is threatened, so the system must take measures to reduce the vehicle's torque output to help restore stability. Once the tire stabilizes and the function is deactivated, the damping coefficient is allowed to slowly increase, gradually restoring the vehicle's torque output to normal levels.

[0091] In some embodiments, after obtaining the gradient-processed requested attenuation coefficient, the method further includes:

[0092] When the wheel acceleration anti-skid flag and / or the slip rate anti-skid flag are activated or exit the activation state, the request attenuation coefficient after gradient processing is filtered using the preset filter coefficient, the filter output value of the previous cycle and the request attenuation coefficient of the current cycle to obtain the request attenuation coefficient after filtering corresponding to the current cycle; when the difference between the request attenuation coefficient after filtering and the target attenuation coefficient is less than the preset difference threshold, the filtering process is exited.

[0093] Specifically, to smooth the damping coefficient changes, thereby providing a more comfortable and stable driving experience, the system performs a further filtering process after determining the requested damping coefficient after gradient processing. This operation aims to eliminate sudden changes in the damping coefficient caused by the activation or deactivation of the wheel acceleration anti-skid flag and / or the slip rate anti-skid flag. To achieve this goal, the system uses a preset filtering coefficient, which is determined based on the vehicle's dynamic performance and stability requirements.

[0094] In one example, when filtering begins, the system considers the filtered output value of the previous cycle and the requested attenuation coefficient of the current cycle. By combining these two parameters and the preset filtering coefficient, the system can obtain the requested attenuation coefficient for the current cycle after filtering. In this way, the system can ensure that the change in the attenuation coefficient is smooth and continuous, thereby avoiding sudden changes in the attenuation coefficient due to function activation or exit. In actual application, the output value after this filtering can be calculated using the following formula:

[0095] y(t)=K·u(t)+(1-K)·y(t-1)

[0096] Where K represents the filter coefficient, u(t) represents the current sampling value, y(t-1) represents the filter output value of the previous cycle, and y(t) represents the output value after current filtering.

[0097] Furthermore, this embodiment of the present application also sets a preset difference threshold. When the difference between the requested attenuation coefficient after filtering and the target attenuation coefficient is less than this threshold, the system will assume that the attenuation coefficient has approached the target value, and no further filtering is required. This design ensures that the system can respond quickly after reaching the target state, thereby providing more flexible and efficient stability control.

[0098] After executing the operations of the above embodiment, the embodiment of the present application will calculate the shaft end request torque based on the shaft end target torque and the request attenuation coefficient after filtering. For example, the shaft end request torque can be calculated using the following formula:

[0099] T req =T raw ×Factor

[0100] Among them, T req Indicates the required torque at the shaft end, T raw Indicates the target torque at the shaft end, and Factor indicates the requested attenuation coefficient after filtering.

[0101] According to the technical solutions provided by the embodiments of this application, these embodiments cleverly utilize wheel acceleration, wheel acceleration change rate, slip rate, and slip rate change rate to identify and respond to low-adhesion conditions. By monitoring and analyzing these parameters in real time, the system can promptly identify whether a wheel is slipping, thereby providing the driver with a more timely and accurate stability control strategy. Specifically, by adjusting the attenuation of the shaft end torque, the system can effectively control the vehicle's maximum driving and braking torque, thereby ensuring vehicle stability on low-adhesion surfaces. This not only improves the vehicle's maneuverability on low-adhesion surfaces but also significantly enhances driving safety, providing the driver with a more comfortable and stable driving experience. Furthermore, this technical solution utilizes a variety of advanced processing techniques, such as gradient processing and filtering, to ensure that the attenuation coefficient changes smoothly and continuously. These designs avoid sudden changes in the attenuation coefficient caused by function activation or deactivation, thereby providing a more continuous and smooth driving experience. Overall, this application provides an efficient, intelligent, and practical low-adhesion stability control solution for new energy vehicles. By combining real-time vehicle parameters, preset mapping relationships and advanced processing technology, this solution can provide drivers with a more stable, safe and comfortable driving experience, thereby significantly improving the performance and safety of new energy vehicles on low-adhesion roads.

[0102] The following are device embodiments of the present application, which can be used to implement the method embodiments of the present application. For details not disclosed in the device embodiments of the present application, please refer to the method embodiments of the present application.

[0103] Figure 2Schematic diagram of the structure of the vehicle stability control device on low-adhesion road provided by the embodiment of the present application. Figure 2 As shown, the vehicle stability control device on the low adhesion road comprises:

[0104] The first judgment module 201 is configured to determine the wheel acceleration and wheel acceleration change rate corresponding to each wheel, and based on the wheel acceleration and wheel acceleration change rate, determine whether the wheel acceleration anti-skid flag is activated;

[0105] The first determining module 202 is configured to determine a wheel acceleration anti-skid target attenuation coefficient based on the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate when the wheel acceleration anti-skid flag is activated;

[0106] The second judgment module 203 is configured to determine the slip rate corresponding to each wheel, and based on the slip rate and a preset slip rate threshold, determine whether the slip rate anti-skid flag is activated;

[0107] The second determining module 204 is configured to determine a slip rate anti-skid target attenuation coefficient based on the slip rate absolute value and the slip rate change rate absolute value when the slip rate anti-skid flag is activated;

[0108] The processing module 205 is configured to determine the attenuation coefficient change gradient when the wheel acceleration anti-skid flag or the slip rate anti-skid flag is activated, and use the attenuation coefficient change gradient to process the requested attenuation coefficient of the current cycle to obtain the gradient-processed requested attenuation coefficient;

[0109] The control module 206 is configured to calculate the shaft end request torque based on the shaft end target torque of the current cycle and the request attenuation coefficient after gradient processing, and transmit the shaft end request torque to the drive motor to perform torque control so as to perform low-adhesion stability control on the vehicle.

[0110] In some embodiments, Figure 2 The first judgment module 201 compares the wheel acceleration and the wheel acceleration change rate corresponding to each wheel respectively, and selects the maximum wheel acceleration and the maximum wheel acceleration change rate; when the maximum wheel acceleration is greater than the first wheel acceleration threshold, and the maximum wheel acceleration change rate is greater than the first wheel acceleration change rate threshold, it is determined that the wheel acceleration anti-skid flag is activated; when within a preset time period, the maximum wheel acceleration is less than the second wheel acceleration threshold, and the maximum wheel acceleration change rate is less than the second wheel acceleration change rate threshold, it is determined that the wheel acceleration anti-skid flag is not activated.

[0111] In some embodiments, Figure 2The first determination module 202 uses the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate to query a predetermined first attenuation coefficient mapping relationship to obtain a wheel acceleration anti-skid target attenuation coefficient; wherein the first attenuation coefficient mapping relationship is used to represent a preset value of the wheel acceleration anti-skid target attenuation coefficient that changes with the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate.

[0112] In some embodiments, Figure 2 The first determination module 202 obtains historical measured data of the vehicle, and sets corresponding wheel acceleration anti-skid target attenuation coefficients for the absolute values of the wheel accelerations and the absolute values of the wheel acceleration change rates based on the historical wheel accelerations and the historical wheel acceleration change rates in the historical measured data, using a predetermined configuration rule for the wheel acceleration anti-skid target attenuation coefficient, and establishes a first attenuation coefficient mapping relationship between the wheel acceleration anti-skid target attenuation coefficient and the absolute values of the wheel accelerations and the absolute values of the wheel acceleration change rates; wherein the configuration rule for the wheel acceleration anti-skid target attenuation coefficient includes a rule that is set with the goal that the larger the absolute values of the wheel accelerations and the absolute values of the wheel acceleration change rates, the smaller the wheel acceleration anti-skid target attenuation coefficient.

[0113] In some embodiments, Figure 2 The second judgment module 203 compares the slip rates corresponding to the various wheels and selects the maximum slip rate. When the maximum slip rate is greater than the slip rate threshold, it is determined that the slip rate anti-skid flag is activated. When the maximum slip rate is less than the slip rate threshold, it is determined that the slip rate anti-skid flag is not activated.

[0114] In some embodiments, Figure 2 The second determination module 204 uses the absolute value of the slip rate and the absolute value of the slip rate change rate to query a predetermined second attenuation coefficient mapping relationship to obtain a slip rate anti-skid target attenuation coefficient; wherein the second attenuation coefficient mapping relationship is used to represent a preset value of the slip rate anti-skid target attenuation coefficient that changes with the absolute value of the slip rate and the absolute value of the slip rate change rate.

[0115] In some embodiments, Figure 2 The second determination module 204 obtains historical measured data of the vehicle, and sets corresponding slip rate anti-skid target attenuation coefficients for the absolute value of the slip rate and the absolute value of the slip rate change rate based on the historical slip rate and the historical slip rate change rate in the historical measured data, using a predetermined configuration rule for the slip rate anti-skid target attenuation coefficient, and establishes a second attenuation coefficient mapping relationship between the slip rate anti-skid target attenuation coefficient and the absolute value of the slip rate and the absolute value of the slip rate change rate; wherein the configuration rule for the slip rate anti-skid target attenuation coefficient includes a rule set with the goal that the larger the absolute value of the slip rate and the absolute value of the slip rate change rate, the smaller the slip rate anti-skid target attenuation coefficient.

[0116] In some embodiments, Figure 2Before determining the attenuation coefficient change gradient, the processing module 205 uses the wheel acceleration anti-skid target attenuation coefficient as the target attenuation coefficient when the wheel acceleration anti-skid flag is in an activated state, or the wheel acceleration anti-skid flag and the slip rate anti-skid flag are both in an activated state; when the wheel acceleration anti-skid flag is in an inactivated state, the slip rate anti-skid target attenuation coefficient is used as the target attenuation coefficient.

[0117] In some embodiments, Figure 2 The processing module 205 uses the vehicle speed and the shaft-end target torque in the current cycle to query the predetermined attenuation coefficient change gradient mapping relationship to obtain the attenuation coefficient change gradient; the attenuation coefficient change gradient mapping relationship is used to characterize the preset value of the attenuation coefficient change gradient as the vehicle speed and the shaft-end target torque change; wherein, the attenuation coefficient change gradient mapping relationship is to use the predetermined attenuation coefficient change gradient configuration rule to set the corresponding attenuation coefficient change gradient for the vehicle speed and the shaft-end target torque, and the attenuation coefficient change gradient mapping relationship is established based on the mapping relationship between the attenuation coefficient change gradient, the vehicle speed and the shaft-end target torque; the attenuation coefficient change gradient configuration rule includes when the wheel acceleration anti-slip flag or the slip rate anti-slip flag is activated, the rule set for controlling the requested attenuation coefficient of the current cycle to drop to the target.

[0118] In some embodiments, Figure 2 After obtaining the request attenuation coefficient after gradient processing, the processing module 205 uses the preset filtering coefficient, the filtering output value of the previous cycle and the request attenuation coefficient of the current cycle to filter the request attenuation coefficient after gradient processing to obtain the request attenuation coefficient after filtering corresponding to the current cycle; when the difference between the request attenuation coefficient after filtering and the target attenuation coefficient is less than the preset difference threshold, the filtering process is exited.

[0119] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0120] An embodiment of the present application also provides a new energy vehicle, including a vehicle controller, a motor controller, a drive motor and a transmission system; the vehicle controller is used to implement the steps of the above-mentioned sliding torque control method under the speed bump working condition to send the final sliding torque to the motor controller; the motor controller is used to control the torque of the drive motor through the transmission system according to the final sliding torque.

[0121] Figure 3 Schematic diagram of the structure of the electronic device 3 provided in the embodiment of the present application. Figure 3As shown, the electronic device 3 of this embodiment includes: a processor 301, a memory 302, and a computer program 303 stored in the memory 302 and executable on the processor 301. When the processor 301 executes the computer program 303, the steps of the above-mentioned method embodiments are implemented. Alternatively, when the processor 301 executes the computer program 303, the functions of the modules / units in the above-mentioned device embodiments are implemented.

[0122] For example, computer program 303 may be divided into one or more modules / units, which are stored in memory 302 and executed by processor 301 to implement the present application. One or more modules / units may be a series of computer program instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of computer program 303 in electronic device 3.

[0123] The electronic device 3 may be a desktop computer, a notebook, a PDA, a cloud server or other electronic device. The electronic device 3 may include but is not limited to a processor 301 and a memory 302. Those skilled in the art will understand that Figure 3 It is only an example of electronic device 3 and does not constitute a limitation of electronic device 3. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device may also include input and output devices, network access devices, buses, etc.

[0124] The processor 301 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0125] The memory 302 can be an internal storage unit of the electronic device 3, such as a hard drive or memory of the electronic device 3. The memory 302 can also be an external storage device of the electronic device 3, such as a plug-in hard drive, a Smart Media Card (SMC), a Secure Digital (SD) card, a flash memory card, etc. equipped on the electronic device 3. Furthermore, the memory 302 can include both an internal storage unit of the electronic device 3 and an external storage device. The memory 302 is used to store computer programs and other programs and data required by the electronic device. The memory 302 can also be used to temporarily store data that has been output or is about to be output.

[0126] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0127] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0128] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0129] In the embodiments provided in this application, it should be understood that the disclosed apparatus / computer equipment and methods can be implemented in other ways. For example, the apparatus / computer equipment embodiments described above are merely schematic. For example, the division of modules or units is merely a logical function division. In actual implementation, there may be other division methods. Multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection of the apparatus or unit, which may be electrical, mechanical or other forms.

[0130] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0131] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0132] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the process in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and when the computer program is executed by the processor, it can implement the steps of the above-mentioned various method embodiments. The computer program may include computer program code, which may be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0133] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A method for controlling vehicle stability on a low-adhesion road, characterized in that: include: determining the wheel acceleration and the wheel acceleration change rate corresponding to each wheel, and judging whether the wheel acceleration anti-skid flag is activated based on the wheel acceleration and the wheel acceleration change rate; When the wheel acceleration anti-skid flag is activated, determining a wheel acceleration anti-skid target attenuation coefficient based on the wheel acceleration absolute value and the wheel acceleration change rate absolute value; determining a slip rate corresponding to each wheel, and determining whether a slip rate anti-skid flag is activated based on the slip rate and a preset slip rate threshold; When the slip rate anti-skid flag is activated, determining a slip rate anti-skid target attenuation coefficient based on the slip rate absolute value and the slip rate change rate absolute value; When the wheel acceleration anti-skid flag or the slip rate anti-skid flag is activated, determining an attenuation coefficient change gradient, and processing a requested attenuation coefficient of a current period using the attenuation coefficient change gradient to obtain a gradient-processed requested attenuation coefficient; Based on the shaft end target torque of the current cycle and the requested attenuation coefficient after gradient processing, the shaft end requested torque is calculated, and the shaft end requested torque is transmitted to the drive motor to perform torque control so as to perform low-adhesion stability control on the vehicle.

2. The method according to claim 1, characterized in that The determining, based on the wheel acceleration and the wheel acceleration change rate, whether the wheel acceleration anti-skid flag is activated includes: Compare the wheel accelerations and wheel acceleration change rates corresponding to each wheel, and select the maximum wheel acceleration and maximum wheel acceleration change rate; When the maximum wheel acceleration is greater than a first wheel acceleration threshold, and the maximum wheel acceleration change rate is greater than a first wheel acceleration change rate threshold, determining that the wheel acceleration anti-skid flag is activated; When, within a preset time period, the maximum wheel acceleration is less than a second wheel acceleration threshold, and the maximum wheel acceleration change rate is less than a second wheel acceleration change rate threshold, it is determined that the wheel acceleration anti-skid flag is not activated.

3. The method according to claim 1, characterized in that Determining the wheel acceleration anti-skid target attenuation coefficient based on the wheel acceleration absolute value and the wheel acceleration change rate absolute value includes: Using the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate, a predetermined first attenuation coefficient mapping relationship is queried to obtain the wheel acceleration anti-skid target attenuation coefficient; wherein, the first attenuation coefficient mapping relationship is used to characterize a preset value of the wheel acceleration anti-skid target attenuation coefficient that changes with the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate.

4. The method according to claim 3, characterized in that The method further comprises: Acquiring historical measured data of the vehicle, and setting corresponding wheel acceleration anti-skid target attenuation coefficients for the wheel acceleration absolute values and the wheel acceleration rate absolute values according to historical wheel accelerations and historical wheel acceleration rate changes in the historical measured data, using a predetermined wheel acceleration anti-skid target attenuation coefficient configuration rule, and establishing a first attenuation coefficient mapping relationship between the wheel acceleration anti-skid target attenuation coefficients and the wheel acceleration absolute values and the wheel acceleration rate absolute values; The configuration rule of the wheel acceleration anti-skid target attenuation coefficient includes a rule set such that the larger the absolute value of the wheel acceleration and the absolute value of the wheel acceleration change rate, the smaller the wheel acceleration anti-skid target attenuation coefficient.

5. The method according to claim 1, wherein The determining, based on the sliding rate and a preset sliding rate threshold, whether the sliding rate anti-slip flag is activated includes: The slip rates corresponding to each wheel are compared, and the maximum slip rate is selected. When the maximum slip rate is greater than the slip rate threshold, it is determined that the slip rate anti-skid flag is activated; when the maximum slip rate is less than the slip rate threshold, it is determined that the slip rate anti-skid flag is not activated.

6. The method according to claim 1, characterized in that The step of determining the anti-skid target attenuation coefficient of the slip rate based on the absolute value of the slip rate and the absolute value of the slip rate change rate includes: The predetermined second attenuation coefficient mapping relationship is queried using the absolute value of the slip rate and the absolute value of the slip rate change rate to obtain the slip rate anti-skid target attenuation coefficient; wherein the second attenuation coefficient mapping relationship is used to characterize the preset value of the slip rate anti-skid target attenuation coefficient that changes with the absolute value of the slip rate and the absolute value of the slip rate change rate.

7. The method according to claim 6, characterized in that The method further comprises: Acquiring historical measured data of the vehicle, setting corresponding slip rate anti-skid target attenuation coefficients for the absolute value of the slip rate and the absolute value of the slip rate change rate based on historical slip rates and historical slip rate change rates in the historical measured data, and establishing a second attenuation coefficient mapping relationship between the slip rate anti-skid target attenuation coefficient and the absolute value of the slip rate and the absolute value of the slip rate change rate; The configuration rule of the slip rate anti-skid target attenuation coefficient includes a rule set with the goal that the larger the absolute value of the slip rate and the absolute value of the slip rate change rate are, the smaller the slip rate anti-skid target attenuation coefficient is.

8. The method according to claim 1, characterized in that Before determining the attenuation coefficient change gradient, the method further includes: When the wheel acceleration anti-skid flag is in an activated state, or when both the wheel acceleration anti-skid flag and the slip rate anti-skid flag are in an activated state, the wheel acceleration anti-skid target attenuation coefficient is used as the target attenuation coefficient; When the wheel acceleration anti-skid flag is in an inactive state, the slip rate anti-skid target attenuation coefficient is used as the target attenuation coefficient.

9. The method according to claim 1, characterized in that Determining the attenuation coefficient change gradient includes: Using the vehicle speed and the shaft end target torque in the current cycle, a predetermined attenuation coefficient change gradient mapping relationship is queried to obtain the attenuation coefficient change gradient; the attenuation coefficient change gradient mapping relationship is used to represent a preset value of the attenuation coefficient change gradient as the vehicle speed and the shaft end target torque change; Among them, the attenuation coefficient change gradient mapping relationship is to use a predetermined attenuation coefficient change gradient configuration rule to set a corresponding attenuation coefficient change gradient for the vehicle speed and the shaft end target torque, and the attenuation coefficient change gradient mapping relationship is established based on the mapping relationship between the attenuation coefficient change gradient, the vehicle speed and the shaft end target torque; the attenuation coefficient change gradient configuration rule includes when the wheel acceleration anti-slip flag or the slip rate anti-slip flag is activated, the rule of controlling the requested attenuation coefficient of the current cycle to drop to the target is set.

10. The method according to claim 1, characterized in that After obtaining the gradient-processed request attenuation coefficient, the method further includes: When the wheel acceleration anti-skid flag and / or the slip rate anti-skid flag is activated or exits the activation state, the request attenuation coefficient after gradient processing is filtered using the preset filter coefficient, the filter output value of the previous cycle and the request attenuation coefficient of the current cycle to obtain the request attenuation coefficient after filtering corresponding to the current cycle; when the difference between the request attenuation coefficient after filtering and the target attenuation coefficient is less than the preset difference threshold, the filtering process is exited.

11. A vehicle stability control device on a low-adhesion road, characterized in that: include: a first judgment module configured to determine the wheel acceleration and the wheel acceleration change rate corresponding to each wheel, and determine whether the wheel acceleration anti-skid flag is activated based on the wheel acceleration and the wheel acceleration change rate; a first determining module configured to determine a wheel acceleration anti-skid target attenuation coefficient based on the wheel acceleration absolute value and the wheel acceleration change rate absolute value when the wheel acceleration anti-skid flag is activated; a second determination module configured to determine a slip rate corresponding to each wheel, and determine whether a slip rate anti-skid flag is activated based on the slip rate and a preset slip rate threshold; a second determining module configured to determine a slip rate anti-skid target attenuation coefficient based on a slip rate absolute value and a slip rate change absolute value when the slip rate anti-skid flag is activated; a processing module configured to, when the wheel acceleration anti-skid flag or the slip rate anti-skid flag is activated, determine an attenuation coefficient change gradient, and process a requested attenuation coefficient of a current period using the attenuation coefficient change gradient to obtain a gradient-processed requested attenuation coefficient; The control module is configured to calculate the shaft end request torque based on the shaft end target torque of the current cycle and the request attenuation coefficient after gradient processing, and transmit the shaft end request torque to the drive motor to perform torque control so as to perform low-adhesion stability control on the vehicle.

12. A new energy vehicle, characterized in that: Including vehicle controller, motor controller, drive motor and transmission system; The vehicle controller is used to implement the method according to any one of claims 1 to 10 to send the shaft end request torque to the motor controller; The motor controller is used to control the torque of the drive motor through the transmission system according to the shaft end request torque.

Images