Method for a traction control system of a vehicle, traction control system, controller

Abstract

The invention provides a method for a traction control system of a vehicle, and the method comprises the steps: judging whether the actual torque is reduced or not and whether the difference value between the actual torque and the request torque of the traction control system is within a preset range or not in a gear shifting process; and under the condition that the actual torque is reduced and the difference value is not within the preset range, the acceleration of the request torque is slowed down until a preset condition is met. The invention further provides a traction force control system and a controller.

Description

Technical Field

[0001] The present application relates to vehicle control technology, and more specifically, to related technologies for a traction control system for a vehicle. Background Art

[0002] For vehicles equipped with automatic transmission (AT) or dual clutch transmission (DCT), if the gears are changed while the traction control system (TCS) is activated, the drive shaft is prone to vibrate after the gear change, causing discomfort to the passengers in the vehicle.

[0003] It is necessary to make improvements to this and provide a more comfortable driving experience. Summary of the invention

[0004] According to one aspect of the present application, a method for a traction control system of a vehicle is provided to improve at least one of the above-mentioned deficiencies.

[0005] The provided method for a traction control system of a vehicle includes: during a gear shift process, determining whether an actual torque decreases and whether a difference between the actual torque and a requested torque of the traction control system is outside a preset range; if the actual torque decreases and the difference is not within a preset range, slowing down the increase rate of the requested torque until a preset condition is met.

[0006] A method for a traction control system for a vehicle is provided, in which, exemplarily, the preset condition is met, including: the duration for slowing down the increase in the requested torque of the traction control system reaches a preset duration; or the driver's requested torque is less than or equal to the requested torque of the traction control system.

[0007] A method for a traction control system for a vehicle is provided, whereby, exemplarily, the slowing down of the increase in the requested torque comprises: calculating a difference between the requested torque of the traction control system and the actual torque; and gradually reducing the requested torque of the traction control system according to the difference.

[0008] According to another aspect of the present application, a traction control system for a vehicle is also provided, comprising a controller, wherein the controller is configured to execute program instructions stored in a memory, and when the controller executes the program instructions: it is determined whether the vehicle is shifting gears; in the case of shifting gears, it is determined whether the actual torque decreases and whether the difference between the actual torque and the requested torque of the traction control system is outside a preset range; in the case of the actual torque decreasing and the difference being outside the preset range, the increase rate of the requested torque is slowed down until a preset condition is met.

[0009] A traction control system for a vehicle is provided, where, exemplarily, the preset condition is satisfied, including: the duration for slowing down the increase rate of the requested torque of the traction control system reaches a preset time length or the driver's requested torque is less than or equal to the requested torque of the traction control system.

[0010] A traction control system for a vehicle is provided, where, for example, the controller, when executing the program instructions, further slows down the increase rate of the requested torque by the following process: calculating the difference between the requested torque of the traction control system and the actual torque; and gradually reducing the requested torque of the traction control system according to the difference.

[0011] A controller is also provided, comprising a memory and a processor, wherein the memory stores program instructions, and the processor is configured to execute the program instructions and implement any one of the above methods when executing the program instructions.

[0012] A computer storage medium is also provided, on which instructions are stored, and the instructions can be executed by a processor and implement any of the above methods when executed. The medium can be a non-transitory storage medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The following will describe the embodiments of the present application in detail with reference to the accompanying drawings so that the present application can be more fully understood, wherein:

[0014] Figure 1 is a flow chart of a method for a traction control system of a vehicle according to some examples of the present application;

[0015] Figure 2 A simple diagram of the structure of the components related to the gear shifting process of the vehicle 2 is shown;

[0016] Figure 3 A structural diagram of a traction control system according to an example of the present application is illustrated;

[0017] Figure 4 It is a schematic diagram of the relationship between the TSC state, shift state, TSC requested torque, and actual engine torque during vehicle driving. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings to clearly and completely describe the implementation methods of the present application. It should be noted that the described implementation methods are only part of the implementation methods of the technical solution of the present application, not all. All other implementation methods obtained by ordinary technicians in this field based on the implementation methods recorded in the application documents without paying creative work are covered by the protection scope of the present application.

[0019] The terms "first", "second", etc. in the specification, claims and drawings of this application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the invention described herein can be implemented in an order other than those illustrated or described herein. In addition, "first" and "second" are used for descriptive purposes only and are not to be understood as expressly or implicitly indicating relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features, and in the description of the embodiments of the present application, unless otherwise stated, "multiple" means two or more.

[0020] As used hereinafter, the words “example” or “exemplarily” or “exemplarily” mean “serving as an example, embodiment, or illustration.” Any embodiment described as “example” or “exemplarily” or “exemplarily” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0021] The Traction Control System (TCS) is designed to enable the vehicle to obtain the best traction under various driving conditions. The traction control system can use the vehicle's existing sensors (such as wheel speed sensors) to detect the speed of the four wheels and obtain the steering wheel steering angle from the vehicle's existing transmission system. When the vehicle accelerates, if the speed difference between the drive wheel and the non-drive wheel is too large, the TCS system controller immediately determines that the driving force is too large and sends a command signal to reduce the engine's output torque to reduce the driving force. This can reduce the slip rate of the drive wheel and stabilize the vehicle body. The TCS system controller grasps the driver's steering intention through the steering wheel angle sensor, and uses the detection values ​​of the left and right wheel speed sensors to determine the speed difference between the left and right wheels; based on this, it determines whether the degree of vehicle steering is consistent with the driver's steering intention. Figure 1 When the vehicle is understeering or oversteering, the TCS system controller can issue a command to reduce the driving force to achieve the driver's steering intention. Traction control system is also called ASR, TRC, etc.

[0022] Figure 1 It is a flow chart of a method for a traction control system of a vehicle according to some examples of the present application. The method is executed when the TCS of the vehicle is activated, and if the TCS of the vehicle is not activated, the method is not executed.

[0023] In step S100, TCS is in the startup state and starts to execute the method.

[0024] In step S101 , during the transmission shifting process, it is determined whether the actual torque decreases and whether the difference between the actual torque and the requested torque of the traction control system is outside a preset range.

[0025] Generally, when the traction control system is turned on and the vehicle is not shifting gears, the actual torque of the engine basically follows the TCS requested torque, that is, the actual torque is basically consistent with the TCS requested torque. It should be understood that due to reasons such as time lag, allowable error in system design, etc., the actual torque and the TCS request at the same time may not be completely equal, but there is a small difference, which should be within a preset range. When the vehicle shifts gears, on the one hand, the actual torque of the engine will decrease and no longer follow the requested torque, and on the other hand, the drive shaft speed will decrease due to the decrease in actual torque, which in turn causes the TCS to issue a request for increased torque, that is, the requested torque will increase. Accordingly, the difference between the actual torque and the requested torque increases.

[0026] When the actual torque decreases and the difference between the actual torque and the requested torque of the traction control system is not within the preset range, that is, outside the preset range, as shown in step S102, the growth rate of the requested torque is slowed down, that is, the requested torque is slowly increased to gradually reduce the difference between the requested torque and the actual torque.

[0027] As an example, if any one of the two conditions, that is, the actual torque decreases or the difference between the actual torque and the requested torque of the traction control system, is not satisfied, then step S101 is continued.

[0028] Slowing down the increase rate of the requested torque is a continuous process, and its duration is, for example, T. According to some examples of the present application, if the duration T reaches a preset duration, the control of slowing down the requested torque is stopped. The preset time is set according to the shift time and is not greater than the shift time. For example, the shift time is usually 1 second, and the preset time is set to a duration between 0.8 seconds and 1 second, including 0.8 seconds and 1 second.

[0029] According to some other examples of the present application, once the driver's request torque is less than or equal to the request torque of the traction control system, the mitigation control of the request torque is stopped.

[0030] According to some examples of the present application, slowing down the increase in the requested torque in step S102 may further include a difference between the current requested torque and the current actual torque, and controlling the increase in the requested torque based on the difference to reduce the difference between the actual torque and the requested torque, or in other words, determining what the requested torque should be based on the difference.

[0031] Figure 2The structure diagram of the components related to the gear shifting process of the vehicle 2 is simply illustrated. The drive system 103 in this example may include a gearbox 102 and an engine 104. A system controller 105 of a traction control system TCS is electrically connected to the drive system 103 to achieve data and signal transmission. The drive system 103 is connected to a drive shaft 106.

[0032] Figure 1 The method shown can be implemented in Figure 2 For example, with TSC on, Figure 2 The vehicle 2 shown can perform the method for the traction control system of the vehicle described above. After the gearbox 102 enters the gear shift process, the system controller 105 of the TCS determines (step S101) whether the actual torque output to the wheel by the drive system 103 decreases and the difference between the actual torque and the requested torque of the traction control system TCS is outside the preset range. The system controller 105 of the TCS can determine the actual torque by the wheel speed sensed by the wheel speed sensor, or obtain a reference amount for determining the actual torque from the vehicle's body stability program ESP. According to the characteristics of the transmission system, during the gear shift process, the output torque of the engine 104 will decrease, and the actual torque output to the wheel will therefore decrease, and the speed of the drive shaft 106 will therefore decrease, which will cause the TCS to increase the requested torque. Once the system controller 105 determines that the actual torque decreases and the difference between the actual torque and the requested torque of the traction control system is not within the preset range, the requested torque is controlled not to increase too fast, that is, the increase rate of the requested torque is slowed down (step S102) so as to gradually reduce the difference between the requested torque and the actual torque. When the preset condition is met, the system controller 105 no longer implements the control of the increase rate of the requested torque.

[0033] According to some examples of the present application, during the gear shifting process, the actual torque can be determined by determining the rotational speed of the drive shaft, that is, a decrease in the rotational speed of the drive shaft indicates a decrease in the actual torque.

[0034] When executing the method according to the example of the present application, during the gear shifting process, when the drive shaft speed decreases (i.e., the actual engine torque decreases), the TCS system still issues a torque increase request. In other words, executing the method according to the present application does not affect the working conditions of the existing gearbox and engine in the vehicle. However, according to the method of the present application, during the gear shifting process, the requested torque can be increased within a controllable and reasonable range by changing the increase rate of the torque increase requested by the TCS system. This makes it possible that after the gear shifting is completed, the requested torque of the TCS system is at a reasonable size, rather than being too large. Accordingly, during the non-gear shifting time, the actual engine torque that follows the torque requested by the TCS system will not be too large, and the drive shaft will not shake due to the sudden excessive driving force after the gear shifting, making the vehicle body relatively stable.

[0035] The method for a traction control system for a vehicle according to each example of the present application can be implemented as one or more programs via a programming language, and these programs can be set into a traction control system, such as an existing traction control system (such as its system controller), in the form of program instructions, so as to implement the method according to any one of the examples of the present application when the traction control system is operating.

[0036] The present application also provides a traction control system for a vehicle. Figure 3 The structure diagram of the traction control system is shown. Figure 3 The controller 300 and memory 302 of the traction control system are shown. It should be noted that only the parts of the traction system related to the present application are shown here, and other existing components such as sensors of the traction system are not shown. In actual applications, the sensors of the traction system may also be directly sensors of other systems of the vehicle, such as wheel speed sensors. Further, the controller 300 can be implemented in the system controller of the traction control system, for example, in combination with the above Figure 2 The system controller 105 described herein. The memory 302 may be an existing memory of the traction control system or an existing memory of the vehicle, as long as the controller 300 can obtain program instructions therefrom. In some cases, the memory 302 may be provided in the controller 105 to obtain program instructions.

[0037] The memory 302 stores program instructions, and the controller 300 is configured to execute these program instructions, and when executing the program instructions, the following process is implemented: judging whether the vehicle is shifting gears; in the case of shifting gears, judging whether the actual torque is decreasing and whether the difference between the actual torque and the requested torque of the traction control system is within a preset range; in the case of the actual torque decreasing and the difference being not within the preset range, slowing down the increase rate of the requested torque until the preset condition is met. The preset condition has been described above and will not be repeated here.

[0038] According to some examples of the present application, when executing program instructions, the controller 300 slows down the increase in the requested torque of the traction control system through the following process: calculating the difference between the requested torque and the actual torque of the traction control system; and gradually reducing the requested torque of the traction control system according to the difference.

[0039] For example Figure 3 The traction control system shown can be used as Figure 2 The traction control system in the embodiment of the present invention, specifically, the controller 300 can be implemented in Figure 2 In the system controller 105 in the embodiment, the memory may be implemented in the traction control system. Figure 2After the vehicle 2 in the embodiment turns on the TCS, the controller 105 executes the instructions stored in the memory, and the above-mentioned combination can be realized during the gear shifting process. Figure 3 Functionality as described.

[0040] A controller is also provided, the controller comprising a memory and a processor. The memory stores program instructions, and the processor is configured to execute these program instructions and thereby implement the above-mentioned Figure 1 Any of the examples of the described method. The controller may be incorporated into an existing traction control system, or may be disposed in the vehicle but may communicate with the traction control system.

[0041] The present application also provides a computer storage medium on which instructions are stored, and when these instructions are executed, the above-mentioned Figure 1 Any one of the examples of the described method. The storage medium is, for example, a non-transitory storage medium.

[0042] Figure 4 The diagram illustrates the relationship between the TSC state, gear shifting state, TSC requested torque, and actual engine torque during vehicle driving, wherein the horizontal axis represents time and the vertical axis varies depending on the curve, but they are all formed in equal proportions. Figure 4 The transmission used by the vehicle in the example is a DCT transmission, the vehicle is driving on an icy road, and the vehicle is a vehicle that has executed the method of the traction control system according to the example of the present application, or has adopted the traction control system according to the example of the present application. It should be noted that, although Figure 4 The illustration shows the driving condition of a vehicle using a DCT transmission on an icy surface, but this does not mean that the examples of this application only work under such vehicle and road conditions. The examples of this application can also be used in other vehicles using transmissions such as AT, and the vehicles can be driven under various road conditions.

[0043] Figure 4 In the figure, the TSC state is indicated by curve 40. When curve 40 is a high signal, it indicates that the traction control system is in the on state. The gear shift state is indicated by curve 42. When curve 42 is a high signal, it indicates that the gear shift state is entered. The TSC request torque is indicated by request torque curve 44, the actual torque of the engine is indicated by actual torque curve 46, and the driver's request torque is indicated by driver torque curve 45.

[0044] When the traction control system is on and the vehicle is not shifting gears, the actual torque of the engine substantially follows the TSC requested torque, for example, the actual torque curve 46 substantially coincides with the requested torque curve 44. When a gear is to be shifted, the actual torque will decrease, and the drive shaft speed will decrease accordingly. For example, during the shift period 420 of the shift curve 42, the change of the actual torque curve 46 no longer follows the TSC requested torque curve 44, and is less than the TSC requested torque. When the actual torque begins to no longer follow the TSC requested torque, that is, when its value becomes less and less than the requested torque, the speed of the drive shaft begins to be lower than the target speed, Figure 4 The curve 50 in FIG. 4 is the drive shaft speed curve and the curve 52 is the target speed curve. When the drive shaft speed is lower than the target speed, and the actual torque curve 46 no longer follows the traction control system request torque curve 44, the TCS starts to increase its request torque, as shown by the curve 44. From the moment when the drive shaft speed is lower than the target speed, the slope of the curve 44 increases, that is, the speed of the request torque increase increases. During the entire shifting process, the speed increase of the curve 44 is controlled. When the duration of the reduction request torque reaches a preset time, the speed increase is no longer controlled. In this process, on the one hand, during the shifting process, the difference between the traction control system request torque and the actual engine torque gradually decreases because the increase speed of the request torque is controlled. At the end of the shifting, the actual engine torque and the traction control system request torque are basically consistent. After the shifting is completed, when the TCS is still working, the actual engine torque and the traction control system request torque are also basically consistent, that is, the former basically follows the latter. In this way, the stability of the vehicle body is guaranteed.

[0045] Although only the operation of a vehicle including a DCT transmission implementing any one of the examples according to the present application on an icy surface is illustrated, it should be understood that the process described above can also be achieved by using other transmissions and / or in other operating conditions as long as any one of the examples according to the present application is implemented.

[0046] Although specific embodiments of the present application have been shown and described in detail to illustrate the principles of the present application, it should be understood that the present application may be implemented in other ways without departing from such principles, for example, the technical features of the various embodiments / examples / examples of the present application may be combined with each other to form new implementation methods.

Claims

1. A method for a traction control system for a vehicle, characterized in that: The method comprises: During the gear shifting process, determining whether the actual torque decreases and whether the difference between the actual torque and the requested torque of the traction control system is outside a preset range; When the actual torque decreases and the difference is outside a preset range, the increase rate of the requested torque is slowed down until a preset condition is met.

2. The method according to claim 1, characterized in that: The preset conditions are met, including: The duration for slowing down the increase in the torque requested by the traction control system reaches a preset time length; or The driver's requested torque is less than or equal to the requested torque of the traction control system.

3. The method according to claim 2, characterized in that The reducing the increase rate of the requested torque includes: calculating a difference between a requested torque of the traction control system and the actual torque; and The requested torque of the traction control system is gradually reduced according to the difference.

4. A traction control system for a vehicle, characterized in that: The system includes a controller configured to execute program instructions stored in a memory, and when the controller executes the program instructions: determining whether the vehicle is shifting gears; In the case of a gear shift, determining whether the actual torque decreases and whether the difference between the actual torque and the requested torque of the traction control system is outside a preset range; When the actual torque decreases and the difference is outside a preset range, the increase rate of the requested torque is slowed down until a preset condition is met.

5. The system according to claim 4, characterized in that The preset conditions are met, including: The duration for slowing down the increase in the torque requested by the traction control system reaches a preset time length; or The driver's requested torque is less than or equal to the requested torque of the traction control system.

6. The system according to claim 5, characterized in that When executing the program instructions, the controller further slows down the increase rate of the requested torque through the following process: calculating a difference between a requested torque of the traction control system and the actual torque; and The requested torque of the traction control system is gradually reduced according to the difference.

7. A controller comprising a memory and a processor, wherein the memory stores program instructions, and the processor is configured to execute the program instructions and implement the method according to any one of claims 1 to 3 when executing the program instructions.

8. A computer storage medium storing instructions, characterized in that: The instructions can be executed by a processor and implement the method according to any one of claims 1 to 3 when executed.

9. The computer storage medium according to claim 8, wherein: The medium is a non-transitory storage medium.

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