Brake system and control method thereof

Abstract

The invention relates to a brake system and a control method thereof. The brake system includes: an electronic control unit that performs a posture control function based on wheel speed sensor values received from wheel speed sensors provided in wheels of a vehicle, determines whether the posture control function fails, and provides a brake signal to perform the posture control function according to a result of the determination; and a brake unit that performs brake control on the wheels on the basis of the brake signal, in which the electronic control unit determines whether a wheel speed sensor has failed or not when the posture control function is executed, and determines the operation mode of the ESC on the basis of the determination result.

Description

Technical Field

[0001] The disclosed invention relates to a brake system and a control method thereof which can maintain a posture control function even when some wheel speed sensors fail. Background Art

[0002] ESC (Electronic Stability Control) is a system that controls the vehicle's driving stability after sensing the vehicle's driving conditions and road conditions. When the vehicle is in a slipping or uncontrollable state during driving, ESC automatically adjusts the brakes and engine to maintain the vehicle's stability. To this end, the vehicle is equipped with a variety of sensors such as wheel speed sensors, acceleration sensors, direction sensors, rotation sensors, etc. ESC analyzes the data collected from the sensors in real time to predict the vehicle's driving conditions and road conditions.

[0003] For example, if the driver loses the direction of the vehicle when braking suddenly or turning, ESC detects this and intervenes to stabilize the vehicle. In addition, ESC adjusts the vehicle's brakes individually to adjust the rotation speed of each wheel. In this way, the vehicle's driving direction is adjusted to prevent skidding or sliding.

[0004] More specifically, ESC analyzes the driving conditions and road conditions of the vehicle based on the data received from the wheel speed sensors to predict the movement of the vehicle, and can sense conditions such as wheel slippage. For example, if the speed of a particular wheel drops sharply compared to other wheels when the driver brakes suddenly or turns, ESC can further apply brakes to the corresponding wheel. This adjusts the direction of the vehicle and prevents wheel slippage, thereby improving the driving stability of the vehicle.

[0005] However, if even one of the wheel speed sensors fails, ESC cannot calculate wheel slip, limiting the ESC function. Therefore, when a wheel speed sensor fails, the vehicle's posture control function cannot be activated, which may adversely affect driving stability. Summary of the invention

[0006] An object of one aspect of the disclosed invention is to provide a vehicle braking system and a control method thereof that can maintain an ESC function even when one wheel speed sensor or two specific wheel speed sensors fail.

[0007] According to one aspect of the disclosed invention, the braking system of a vehicle may include: an electronic control unit, which performs a posture control function based on the wheel speed sensor value received from the wheel speed sensor provided on each wheel of the vehicle, and determines whether the posture control function fails, and provides a braking signal according to the determination result so as to perform the posture control function; and a braking unit, which performs braking control on the wheel based on the above-mentioned braking signal, wherein the above-mentioned electronic control unit determines whether the wheel speed sensor fails when performing the posture control function, and determines the action mode of the ESC according to the determination result.

[0008] In the event of a failure of one wheel speed sensor or a failure of both wheel speed sensors of the front wheels or both wheel speed sensors of the rear wheels, the electronic control unit may operate in the ESC limited mode.

[0009] In a state where two wheel speed sensors fail and any one of the front wheel speed sensors and any one of the rear wheel speed sensors fail, the electronic control unit may operate in the ESC disable mode.

[0010] In the event that three or more wheel speed sensors fail, the electronic control unit may operate in an ESC disable mode.

[0011] In the absence of a failed wheel speed sensor, the electronic control unit may operate in the ESC normal mode.

[0012] In the ESC limited mode, when the two wheel speed sensors of the rear wheels fail, the electronic control unit can determine the oversteer or understeer condition, and provide a braking signal to the braking part of any one of the front wheels based on the determination result.

[0013] In an oversteering condition, the electronic control unit may provide the braking signal to a braking portion of a wheel on the outside of the front wheels in the direction of rotation of the vehicle.

[0014] In an understeering condition, the electronic control unit may provide the braking signal to a braking portion of a wheel on the inner side of the front wheel in the direction of rotation of the vehicle.

[0015] In the above-mentioned ESC limit mode, when the two vehicle speed sensors of the front wheels fail, the above-mentioned electronic control unit can determine the oversteer or understeer condition, and provide a braking signal to the braking part of any one of the rear wheels based on the judgment result.

[0016] In an oversteering condition, the electronic control unit may provide the braking signal to a braking portion of a wheel on the outside of the rear wheels in the direction of rotation of the vehicle.

[0017] In an understeering condition, the electronic control unit may provide the braking signal to a braking portion of a wheel on the inner side of the rear wheels in the direction of rotation of the vehicle.

[0018] When the yaw difference is below a first threshold, the electronic control unit may determine that the vehicle is in an understeering condition, and when the yaw difference is above a second threshold, the electronic control unit may determine that the vehicle is in an oversteering condition.

[0019] The electronic control unit may provide a target wheel slip obtained based on the yaw angle deviation (Yawdifference) through the braking signal. The braking unit that receives the braking signal obtains a target braking pressure based on the target wheel slip and then performs braking control on the corresponding wheel.

[0020] According to one aspect of the disclosed invention, the braking system of a vehicle may include: a step of executing a posture control function based on a wheel speed sensor value received from a wheel speed sensor provided at each wheel of the vehicle; a step of determining whether the posture control function fails; a step of determining whether the wheel speed sensor fails when the posture control function can be executed; a step of determining the availability of the posture control function when the wheel speed sensor fails; and a step of performing an action in an ESC restricted mode when the posture control function can be executed.

[0021] In the step of determining the availability of the posture control function when the above-mentioned wheel speed sensor fails, it can be determined that the posture control function can be executed when one wheel speed sensor fails, or when both wheel speed sensors of the front wheels or both wheel speed sensors of the rear wheels fail.

[0022] In the event of a failure of the above-mentioned wheel speed sensors, in the step of determining the availability of the posture control function, if there are two failed wheel speed sensors and if either one of the front wheel speed sensors or one of the rear wheel speed sensors fails, it can be determined that the posture control function cannot be executed, thereby operating in the ESC prohibited mode.

[0023] The control method may further include, after the step of determining the availability of the posture control function when the wheel speed sensors fail, the step of operating in an ESC disable mode when three or more wheel speed sensors fail.

[0024] When the above-mentioned posture control function can be performed, in the step of operating in the ESC limited mode, when the two wheel speed sensors of the rear wheels fail, oversteer or understeer can be determined, and a braking signal can be provided to the braking part of any one of the front wheels based on the determination result. When the two wheel speed sensors of the front wheels fail, the above-mentioned braking signal can be provided to the braking part of any one of the rear wheels based on the determination result.

[0025] In an oversteering condition, the above-mentioned braking signal can be provided to the braking part of the wheel on the outer side of the front wheel or the rear wheel in the direction of rotation of the vehicle. In an understeering condition, the above-mentioned braking signal can be provided to the braking part of the wheel on the inner side of the front wheel or the rear wheel in the direction of rotation of the vehicle.

[0026] When the yaw angle deviation (Yaw difference) is below a first threshold, it can be determined as an understeer condition, and when it is above a second threshold, it can be determined as an oversteer condition. The above-mentioned braking signal provides a target wheel slip obtained based on the above-mentioned yaw angle deviation (Yaw difference), and the target braking pressure is obtained based on the above-mentioned target wheel slip, and then braking control of the corresponding wheel is performed. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 FIG. 1 is a diagram schematically showing a configuration of a vehicle braking system according to an embodiment.

[0028] Figure 2 is a flow chart showing a posture control method of a vehicle according to an embodiment.

[0029] Figure 3 is a diagram showing a braking control method in an ECS normal mode according to an embodiment.

[0030] Figure 4 1 is a diagram showing ECS ​​control and parameter changes related thereto in a wheel speed sensor failure condition according to an embodiment.

[0031] Figure 5 is a diagram showing an ESC control scheme under a wheel speed sensor failure condition according to an embodiment. DETAILED DESCRIPTION

[0032] The same reference numerals throughout the specification represent the same constituent elements. This specification does not describe all elements of the multiple embodiments, and omits general content in the technical field to which the disclosed invention belongs or content repeated between multiple embodiments. The terms "part, module, component, block" used in the specification can be implemented by software or hardware. Depending on the embodiment, multiple "parts, modules, components, blocks" can be implemented with one constituent element or one "part, module, component, block" can include multiple constituent elements.

[0033] Throughout the specification, when it is stated that a certain part is “connected” to another part, it includes not only a direct connection but also an indirect connection. The indirect connection includes a connection through a wireless communication network.

[0034] Furthermore, when a certain part is described as “comprising” a certain constituent element, unless otherwise described, it means that other constituent elements may also be included, rather than excluding other constituent elements.

[0035] The terms "first" and "second" are used to distinguish one constituent element from other constituent elements, and the constituent elements are not limited to the above terms.

[0036] An expression in the singular includes an expression in the plural unless the context indicates an obvious exception.

[0037] In each step, identification symbols are used only for ease of explanation and are not used to explain the order of the steps. If a specific order is not clearly stated in the context, the steps may be implemented in an order different from the stated order.

[0038] The working principle and multiple embodiments of the disclosed invention are described below with reference to the accompanying drawings.

[0039] Figure 1 FIG. 1 is a diagram schematically showing a configuration of a vehicle brake system according to an embodiment.

[0040] Reference Figure 1 According to an embodiment of the present invention, the braking system of a vehicle may include an electronic control unit 100, a left front wheel speed sensor 51, a right front wheel speed sensor 52, a left rear wheel speed sensor 53, a right rear wheel speed sensor 54, a left front wheel braking unit 10, a right front wheel braking unit 20, a left rear wheel braking unit 30 and a right rear wheel braking unit 40.

[0041] The left front wheel speed sensor 51, the right front wheel speed sensor 52, the left rear wheel speed sensor 53 and the right rear wheel speed sensor 54 are arranged on each wheel of the vehicle, and the wheel speed sensor value can be obtained by sensing the rotation speed of the wheel.

[0042] The electronic control unit 100 may perform a posture control function based on wheel speed sensor values ​​received from the left front wheel speed sensor 51 , the right front wheel speed sensor 52 , the left rear wheel speed sensor 53 , and the right rear wheel speed sensor 54 .

[0043] The electronic control unit 100 may determine whether the gesture control function has failed.

[0044] When the electronic control unit 100 determines whether the posture control function fails, it does not consider whether the wheel speed sensor fails. It is only determined whether the wheel speed sensor fails when the posture control function is executed. This is because the purpose of the present invention is to maintain the posture control function even when the wheel speed sensor fails.

[0045] If it is determined that the posture control function has failed, the posture control function is not executed.

[0046] In the case where the posture control function has not failed, the electronic control unit 100 may provide a braking signal to the braking portion in order to perform the posture control function.

[0047] The electronic control unit 100 can determine whether the wheel speed sensor fails when executing the posture control function, and determine the operation mode of ESC (Electronic Stability Control) according to the determination result.

[0048] When one wheel speed sensor fails or two wheel speed sensors fail and neither one of the front wheel speed sensors nor one of the rear wheel speed sensors fails, the electronic control unit 100 may operate in the ESC limited mode.

[0049] In a state where two wheel speed sensors fail and any one of the front wheel speed sensors and any one of the rear wheel speed sensors fail, the electronic control unit 100 may operate in the ESC disable mode.

[0050] When the number of failed wheel speed sensors is three or more, the electronic control unit 100 may operate in the ESC disable mode.

[0051] In the absence of a failed wheel speed sensor, the electronic control unit 100 may operate in the ESC normal mode.

[0052] In the ESC limited mode, when the failed wheel speed sensor exists only on the rear wheel, the electronic control unit 100 determines the oversteer or understeer condition and provides a braking signal to the braking part of any one of the front wheels according to the determination result.

[0053] In the oversteering condition, the electronic control unit 100 may provide the above-mentioned braking signal to the braking portion of the wheel on the outside of the front wheels in the vehicle rotation direction.

[0054] In the understeering condition, the electronic control unit 100 may provide the above-mentioned braking signal to the braking portion of the inner wheel in the vehicle rotation direction among the front wheels.

[0055] In the ESC limited mode, when the failed wheel speed sensor only exists on the front wheel, the electronic control unit 100 determines the oversteer or understeer condition, and based on the determination result, provides a braking signal to the braking part of any one of the rear wheels.

[0056] In an oversteering condition, the electronic control unit 100 may provide the above-mentioned braking signal to the braking portion of the wheel on the outside of the rear wheels in the direction of rotation of the vehicle.

[0057] In the understeering condition, the electronic control unit 100 may provide the above-mentioned braking signal to the braking portion of the inner wheel in the vehicle rotation direction among the rear wheels.

[0058] When the yaw difference is below a first threshold, the electronic control unit 100 may determine that the vehicle is in an understeering state. When the yaw difference is above a second threshold, the electronic control unit 100 may determine that the vehicle is in an oversteering state.

[0059] The electronic control unit 100 may provide a target wheel slip obtained based on the yaw angle deviation (Yawdifference) through the brake signal.

[0060] In the case of oversteering in the ESC normal mode, the electronic control unit 100 can provide a braking signal to the braking part of the wheel on the outside of the front wheel in the direction of vehicle rotation. In the case of understeering, the electronic control unit 100 can provide a braking signal to the braking part of the wheel on the inside of the rear wheel in the direction of vehicle rotation.

[0061] The braking unit may receive the braking signal and obtain a target braking pressure based on the target wheel slip, thereby performing braking control on the corresponding wheel.

[0062] The braking portion may include a left front wheel braking portion 10 , a right front wheel braking portion 20 , a left rear wheel braking portion 30 , and a right rear wheel braking portion 40 .

[0063] The braking unit can perform braking control on the corresponding wheel based on the above braking signal.

[0064] The electronic control unit 100, the left front wheel speed sensor 51, the right front wheel speed sensor 52, the left rear wheel speed sensor 53, the right rear wheel speed sensor 54, the left front wheel brake unit 10, the right front wheel brake unit 20, the left rear wheel brake unit 30, and the right rear wheel brake unit 40 can communicate with each other through the vehicle communication network (NT). For example, a plurality of electrical devices included in the vehicle can send and receive data through Ethernet, Media Oriented Systems Transport (MOST), Flexray, Controller Area Network (CAN), Local Interconnect Network (LIN), etc.

[0065] Figure 2 is a flow chart showing a posture control method of a vehicle according to an embodiment.

[0066] Reference Figure 2 The vehicle posture control method may include: in a braking system of a vehicle that performs a posture control function based on a wheel speed sensor value received from a wheel speed sensor provided on each wheel of the vehicle, a step (S1) of determining whether a posture control function has failed, a step (S2) of determining whether a wheel speed sensor has failed if the posture control function can be performed, a step (S3) of determining the availability of the posture control function if the wheel speed sensor has failed, and a step (S5) of operating in an ESC restricted mode if the posture control function can be performed.

[0067] In the step (S1) of determining whether the posture control function has failed, whether the wheel speed sensor has failed is not considered. Only when the posture control function is executed is it determined whether the wheel speed sensor has failed (S2). This is because the purpose of the present invention is to maintain the posture control function even when the wheel speed sensor has failed.

[0068] In the case where the posture control function can be executed, the step (S2) of determining whether the wheel speed sensor is faulty may further include: in the case where the wheel speed sensor is not faulty, the step (S6) of operating in the ESC normal mode.

[0069] In the event of a failure of the above-mentioned wheel speed sensor, in the step (S3) of determining the availability of the posture control function, when there is only one wheel speed sensor that fails or when there are two wheel speed sensors that fail and neither one of the front wheel nor one of the rear wheel speed sensors fails, it can be determined that the posture control function can be executed.

[0070] In the event that the above-mentioned wheel speed sensors fail, the step (S3) of determining the availability of the posture control function may further include: when there are two failed wheel speed sensors and any one of the front wheel speed sensors and any one of the rear wheel speed sensors fail, determining that the posture control function cannot be executed, and performing the operation in the ESC prohibition mode (S7).

[0071] In the step (S3) of determining the availability of the posture control function when the wheel speed sensors fail, the ESC disable mode may be used when three or more wheel speed sensors fail.

[0072] When the above-mentioned posture control function can be performed, in the action step (S5) performed in the ESC limited mode, when the faulty wheel speed sensor only exists on the rear wheel, the oversteer or understeer condition can be judged, and a braking signal is provided to the braking part of any one of the front wheels based on the judgment result. When the faulty wheel speed sensor only exists on the front wheel, the above-mentioned braking signal is provided to the braking part of any one of the rear wheels based on the judgment result.

[0073] In an oversteering condition, the above-mentioned braking signal can be provided to the braking part of the wheel on the outer side of the front wheel or the rear wheel in the direction of rotation of the vehicle. In an understeering condition, the above-mentioned braking signal can be provided to the braking part of the wheel on the inner side of the front wheel or the rear wheel in the direction of rotation of the vehicle.

[0074] When the yaw angle deviation (Yaw difference) is below a first threshold, it is determined to be an understeering condition, and when it is above a second threshold, it is determined to be an oversteering condition. A target wheel slip obtained based on the yaw angle deviation (Yaw difference) is provided through the above-mentioned braking signal, and a target braking pressure is obtained based on the above-mentioned target wheel slip, and braking control is performed on the corresponding wheel.

[0075] In step S6 of the ESC normal mode, when an oversteering condition occurs, a braking signal can be provided to the braking portion of the wheel on the outside of the front wheel in the direction of vehicle rotation, and when an understeering condition occurs, a braking signal can be provided to the braking portion of the wheel on the inside of the rear wheel in the direction of vehicle rotation.

[0076] Below Figure 3Step S6 is described as an example. When the vehicle turning left is in an oversteering condition, a brake signal can be provided to the right front wheel brake unit 20 in the ESC normal mode. On the contrary, when the vehicle turning right is in an oversteering condition, a brake signal can be provided to the left front wheel brake unit 10 in the ESC normal mode. And, when the vehicle turning left is in an understeering condition, a brake signal can be provided to the left rear wheel brake unit 30 in the ESC normal mode. On the contrary, when the vehicle turning right is in an understeering condition, a brake signal can be provided to the right rear wheel brake unit 40 in the ESC normal mode.

[0077] Figure 4 is a diagram showing ECS ​​control and parameter changes related thereto in a wheel speed sensor failure condition according to an embodiment, Figure 5 is a diagram illustrating an ESC control scheme for a wheel speed sensor failure condition according to an embodiment.

[0078] Reference Figures 4 to 5 When the actual yaw angle deviation according to the steering angle change is below the first threshold value A, it can be determined as an understeering condition. When the actual yaw angle deviation according to the steering angle change is below the second threshold value B, it can be determined as an oversteering condition.

[0079] According to the oversteer and / or understeer condition and the ESC mode, the electronic control unit 100 may provide a braking signal to a braking portion of a predetermined wheel, ie, a target wheel slip obtained based on the yaw difference.

[0080] like Figure 5 It is shown that the electronic control unit 100 operates in the ESC limited mode when one wheel speed sensor fails or when two wheel speed sensors fail and neither one of the front wheel speed sensors nor one of the rear wheel speed sensors fails.

[0081] In all other cases, the system operates in ESC disabled mode.

[0082] When operating in the ESC limited mode, the electronic control unit 100 is configured to control only one wheel in an oversteering or understeering condition.

[0083] As described above, when the failed wheel speed sensor exists only in the rear wheel, a control signal is provided to the braking portion of the outer wheel in the vehicle rotation direction among the front wheels (oversteering condition) or the braking portion of the inner wheel (understeering condition).

[0084] Similarly, when the failed wheel speed sensor exists only in the front wheel, a control signal is provided to the braking portion of the outer wheel wheel in the vehicle's rotation direction among the rear wheels (oversteer condition) or the braking portion of the inner wheel wheel (understeer condition).

[0085] According to one aspect of the disclosed invention, it is possible to provide a brake system and method that can perform a posture control function even when one or two specific wheel speed sensors fail.

[0086] As a result, even when the wheel speed sensor fails, the running stability of the vehicle can be maintained.

[0087] The above description is only an example of the technical idea of ​​the present invention. A person skilled in the art of the present invention can bring various modifications and variations without departing from the essential characteristics of the present invention. Therefore, the multiple embodiments disclosed in the present invention are used to illustrate the present invention, but are not intended to limit the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited to these embodiments. The scope of protection of the present invention should be interpreted based on the claims, and all technical ideas within the equivalent scope thereof are included in the scope of protection of the present invention.

Claims

1. A braking system for a vehicle, comprising: an electronic control unit that executes a posture control function based on wheel speed sensor values ​​received from wheel speed sensors provided at each wheel of the vehicle, determines whether the posture control function fails, and provides a brake signal in accordance with the determination result so as to execute the posture control function; and a brake unit that performs brake control on the wheel based on the brake signal, The electronic control unit determines whether the wheel speed sensor is faulty when executing the posture control function, and determines the ESC action mode according to the determination result.

2. The vehicle braking system according to claim 1, wherein: When one wheel speed sensor fails, or when both wheel speed sensors of the front wheels or both wheel speed sensors of the rear wheels fail, the electronic control unit operates in the ESC limited mode.

3. The vehicle braking system according to claim 1, wherein: In a state where two wheel speed sensors fail and any one of the front wheel speed sensors and any one of the rear wheel speed sensors fail, the electronic control unit operates in the ESC disable mode.

4. The vehicle braking system according to claim 1, wherein: When three or more wheel speed sensors fail, the electronic control unit operates in the ESC disable mode.

5. The vehicle braking system according to claim 1, wherein: When there is no failed wheel speed sensor, the electronic control unit operates in the ESC normal mode.

6. The braking system of a vehicle according to claim 2, wherein: In the ESC limited mode, when two wheel speed sensors of the rear wheels fail, the electronic control unit determines an oversteer or understeer condition and provides a braking signal to the braking portion of any one of the front wheels based on the determination result.

7. The vehicle braking system according to claim 6, wherein: In an oversteering condition, the electronic control unit provides the braking signal to a braking portion of a wheel on the outside of the front wheels in the direction of rotation of the vehicle.

8. The vehicle braking system according to claim 6, wherein: In an understeering condition, the electronic control unit provides the braking signal to a braking portion of a wheel on the inner side of the front wheel in the direction of rotation of the vehicle.

9. The braking system of a vehicle according to claim 2, wherein: In the ESC limited mode, when the two vehicle speed sensors of the front wheels fail, the electronic control unit determines an oversteer or understeer condition, and provides a braking signal to the braking part of any one of the rear wheels based on the determination result.

10. The vehicle braking system according to claim 9, wherein: In an oversteering condition, the electronic control unit provides the braking signal to a braking portion of a wheel on the outside of the rear wheels in the direction of rotation of the vehicle.

11. The vehicle braking system according to claim 9, wherein: In an understeering condition, the electronic control unit provides the braking signal to a braking portion of a wheel on the inner side of the rear wheels in the direction of rotation of the vehicle.

12. The vehicle braking system according to claim 6, wherein: When the yaw angle deviation is below a first threshold, the electronic control unit determines that an understeering condition exists, and when the yaw angle deviation is above a second threshold, the electronic control unit determines that an oversteering condition exists.

13. The vehicle braking system according to claim 12, wherein: The electronic control unit provides a target wheel slip obtained based on the yaw angle deviation through the brake signal. The braking unit that receives the braking signal obtains the target braking pressure based on the target wheel slip and then performs braking control on the corresponding wheel.

14. A method for controlling a braking system of a vehicle, comprising: a step of executing a posture control function based on a wheel speed sensor value received from a wheel speed sensor provided at each wheel of the vehicle; Steps for determining whether the posture control function has failed; In the case where the posture control function can be executed, a step of determining whether the wheel speed sensor is faulty or not; the step of determining availability of a posture control function in the event of a wheel speed sensor failure; as well as Steps to perform actions in ESC restricted mode when the gesture control function can be executed.

15. The control method according to claim 14, wherein: In the step of determining the availability of the posture control function in the event of a malfunction of the wheel speed sensor, When one wheel speed sensor fails or when both wheel speed sensors of the front wheels or both wheel speed sensors of the rear wheels fail, it is determined that the posture control function can be executed.

16. The control method according to claim 14, wherein: In the step of determining the availability of the posture control function in the event of a malfunction of the wheel speed sensor, In a state where two wheel speed sensors fail and either one of the front wheel speed sensors or one of the rear wheel speed sensors fails, it is determined that the posture control function cannot be executed, and the system operates in the ESC disabled mode.

17. The control method according to claim 14, wherein: After the step of determining the availability of the posture control function in the event of a malfunction of the wheel speed sensor, the method further includes: A step of operating in an ESC inhibit mode when three or more wheel speed sensors fail.

18. The control method according to claim 15, wherein: In the case where the above posture control function can be performed, in the steps of performing actions in ESC limited mode, In the event of a failure of the two wheel speed sensors of the rear wheels, the oversteering or understeering condition is determined, and a braking signal is provided to the brake part of any one of the front wheels according to the determination result. In the event that the two wheel speed sensors of the front wheels fail, the brake signal is provided to the brake unit of any one of the rear wheels according to the determination result.

19. The control method according to claim 18, wherein: In the oversteering condition, the above-mentioned braking signal is provided to the braking part of the front wheel or the rear wheel on the outer side of the vehicle's rotation direction. In an understeering condition, the brake signal is provided to a brake portion of a wheel on the inside of the front wheel or the rear wheel in the direction of rotation of the vehicle.

20. The control method according to claim 19, wherein: When the yaw angle deviation is below a first threshold, it is determined to be an understeering condition, and when it is above a second threshold, it is determined to be an oversteering condition. providing a target wheel slip obtained based on the yaw angle deviation through the braking signal, After the target braking pressure is obtained based on the target wheel slip, braking control is performed on the corresponding wheel.

Images