Brake control method, controller, brake control system, and vehicle

Abstract

The application discloses a brake control method, a controller, a brake control system and a vehicle. The method comprises: in the case that the brake system of the vehicle is abnormal, executing an abnormal control scheme corresponding to the abnormal state of the brake system; wherein in the case that the abnormal state is that the brake system cannot send a feedback signal to the controller, a corresponding first abnormal control scheme comprises reducing the motor brake and increasing the hydraulic brake. In this way, in the case that the brake system communication is abnormal, the brake can be realized by increasing the hydraulic brake.

Description

Technical Field

[0001] This application relates to the field of vehicle braking technology, and more specifically, to a braking control method, a controller, a braking control system, and a vehicle. Background Technology

[0002] The vehicle's braking system is crucial for driving safety. However, the relevant technologies are not perfect in handling abnormal situations in the vehicle's braking system. Summary of the Invention

[0003] This application provides a braking control method, including:

[0004] In the event of a malfunction in the vehicle's braking system, an abnormal control scheme corresponding to the abnormal state of the braking system is executed. Specifically, if the abnormal state is that the braking system cannot send a feedback signal to the controller, the corresponding first abnormal control scheme includes reducing the electric motor braking and increasing the hydraulic braking. This allows braking to be achieved by increasing the hydraulic braking even in the event of a communication failure in the braking system.

[0005] In some implementations, the first anomaly control scheme further includes: attenuating the vehicle's maximum permissible feedback capability.

[0006] In some implementations, the attenuation of the vehicle's maximum permissible feedback capability is either gradual or smooth.

[0007] In some implementations, in the first anomaly control scheme:

[0008] The electric motor braking is gradually reduced or smoothly reduced, while the hydraulic braking is gradually increased or smoothly increased.

[0009] In some implementations, the first anomaly control scheme further includes:

[0010] Switch to pure hydraulic braking.

[0011] In some implementations, the first abnormal control scheme further includes: when the deceleration of the vehicle is less than the expected deceleration, controlling the braking system to increase the motor braking, wherein the expected deceleration is obtained based on the driver's deceleration intention and / or deceleration operation.

[0012] In some implementations, if the controller verifies an anomaly in the lifeframe corresponding to the braking system, the anomaly is that the braking system is unable to send a feedback signal to the controller.

[0013] In some implementations, when the abnormal state is a braking system failure, the corresponding second abnormal control scheme includes: controlling the motor to apply auxiliary braking torque based on the vehicle's real-time deceleration and required deceleration.

[0014] In some embodiments, the abnormal state is a braking system failure in the event of hydraulic braking failure of the braking system.

[0015] In some implementations, the hydraulic braking of the braking system fails when the difference between the vehicle's real-time deceleration and the required deceleration exceeds a reasonable range.

[0016] In some implementations, the required deceleration is obtained based on the brake push rod travel and the vehicle speed, or the required acceleration is obtained based on the driver's braking intention and the normal vehicle speed.

[0017] In some implementations, the auxiliary braking torque is less than or equal to an upper torque limit, which is related to the vehicle's overall power generation capacity.

[0018] Secondly, this application also provides a controller, including a processor connected to a memory storing a computer program, the processor executing the computer program to implement the method described in any of the above embodiments.

[0019] Thirdly, this application also provides a braking control system, including a braking system and a controller as described in the second aspect.

[0020] In some implementations, the controller is a domain controller or a central controller.

[0021] Fourthly, this application also provides a vehicle including the controller described in the second aspect above;

[0022] Or it may include the braking control system mentioned in the third aspect above. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the braking control system provided in an embodiment of this application;

[0025] Figure 2 This is a schematic flowchart of the braking control method provided in the embodiments of this application;

[0026] Figure 3 A flowchart illustrating the first anomaly control scheme provided in certain embodiments of this application;

[0027] Figure 4 A flowchart illustrating the second anomaly control scheme provided in certain embodiments of this application. Detailed Implementation

[0028] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Furthermore, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application.

[0029] In related technologies, vehicles are equipped with an integrated power brake (IPB) system. IPB is an electro-hydraulic integrated braking system that includes multiple sub-functions. IPB integrates hydraulic braking and electric motor braking.

[0030] The IPB connects to at least one controller of the vehicle, and the IPB can implement hydraulic braking and electric braking functions through the controller.

[0031] Optionally, the controller can be a domain controller or a central controller. A domain controller can be a power domain controller or a zone controller.

[0032] This application provides a braking control system, including an IPB and a controller. The IPB integrates hydraulic braking and electric braking functions.

[0033] like Figure 1In one optional embodiment, the IPB can control the hydraulic brake actuator to perform hydraulic braking. The controller calculates the maximum permissible feedback capability of the current vehicle based on the vehicle status and sends it to the IPB. After receiving the maximum permissible feedback capability from the controller, the IPB calculates the IPB braking feedback target torque and master cylinder pressure through its internal logic. The IPB braking feedback target torque is used to control the motor for motor braking, and the master cylinder pressure is used to control the hydraulic brake actuator for hydraulic braking. The IPB braking feedback target torque will not exceed the maximum permissible feedback capability, and the master cylinder pressure is directly related to the IPB braking feedback target torque. The IPB-calculated IPB braking feedback target torque is sent to the controller, which converts it into a motor target feedback torque to control the motor to be in generator mode, applying regenerative braking force. Simultaneously, the master cylinder pressure calculated by the IPB generates hydraulic braking force through the hydraulic brake actuator. The combined action of the regenerative braking force and the hydraulic braking force achieves vehicle deceleration.

[0034] The controller controls the vehicle's regenerative braking force and hydraulic braking force by adjusting the maximum permissible feedback capability sent to the IPB and sending the target feedback torque to the motor. The controller can combine message communication fault diagnosis and vehicle deceleration monitoring to determine the current braking status of the vehicle, and thus determine whether the IPB system is experiencing communication abnormalities or braking system failure. For example, when the IPB cannot send a feedback signal (IPB braking feedback target torque) to the controller, the controller determines that the IPB system communication is abnormal. The controller cannot effectively know the IPB system status and the IPB braking feedback target torque, and cannot establish the relationship between electro-hydraulic braking. The controller can adjust the maximum permissible feedback capability sent to the IPB, gradually attenuating the maximum permissible feedback capability, affecting the IPB braking feedback target torque and master cylinder pressure, thus achieving controller control of the IPB electro-hydraulic coupling, and consequently affecting the vehicle's regenerative braking force and hydraulic braking force, thus controlling the vehicle's deceleration. Conversely, when the controller determines that the IPB is unable to apply hydraulic braking force, indicating an IPB system failure, the controller adjusts the vehicle's motor target feedback torque, controlling the motor to generate power and apply regenerative braking force, thereby affecting the vehicle's regenerative braking force and achieving PDC deceleration control of the vehicle. The electric motor compensates for the hydraulic braking. Throughout the braking process, the controller continuously monitors the vehicle's deceleration to ensure that even in the event of an IPB system communication failure or system malfunction, the vehicle remains within a reasonable deceleration range, thus achieving the driver's braking intention.

[0035] This application provides a braking control method, including the steps of: executing an abnormal control scheme corresponding to the abnormal state of the braking system when the braking system of the vehicle is abnormal; wherein, when the abnormal state is that the braking system cannot send a feedback signal to the controller, the corresponding first abnormal control scheme includes reducing the electric motor braking and increasing the hydraulic braking.

[0036] like Figure 2 As shown, in some embodiments of this application, the braking method includes the following steps:

[0037] S01, The controller recognizes that the driver intends to brake.

[0038] Optionally, the controller can obtain the driver's braking intention by collecting throttle and brake pedal depth data. Alternatively, the controller can obtain the driver's braking intention through mechanical buttons, a gearshift, electronic input, voice commands, or action commands.

[0039] For example, when the accelerator is released and the brake is pressed, it can be assumed that the driver intends to brake.

[0040] S02. The controller checks for communication abnormalities.

[0041] The controller checks whether it can receive the feedback signal sent by IPB normally.

[0042] Whether there is a communication problem between the IPB and the controller can be detected by checking whether the feedback signal sent by the IPB can be received normally.

[0043] Optionally, the controller communicates with the IPB via a CAN bus. The controller verifies the IPB's lifeframe to determine if it can normally receive the feedback signal sent by the IPB. If the lifeframe is abnormal, it is assumed that the controller cannot normally receive the feedback signal sent by the IPB, and the communication between the controller and the IPB is abnormal. If the lifeframe is normal, it is assumed that the communication between the controller and the IPB is normal.

[0044] S03, The controller monitors the vehicle's deceleration in real time.

[0045] Optionally, the controller can acquire the current vehicle speed signal via the CAN bus, perform Kalman filtering and mean filtering on the vehicle speed signal to obtain the processed vehicle speed signal, calculate the vehicle deceleration corresponding to the vehicle speed using the least squares method on the processed vehicle speed signal, and perform Kalman filtering and mean filtering on the vehicle deceleration to obtain the processed vehicle deceleration.

[0046] S04. The controller determines whether the IPB system has failed.

[0047] The vehicle deceleration obtained in step S03 is compared with the required deceleration. If the difference between the real-time deceleration and the preset deceleration exceeds a reasonable range, the IPB system is determined to be abnormal and the IPB system is not capable of applying hydraulic braking force. If the real-time deceleration and the preset deceleration are within a reasonable range, the IPB system is capable of applying hydraulic braking force and the IPB system is not faulty.

[0048] Optionally, the required deceleration is obtained based on the brake push rod travel and the vehicle speed, or the required acceleration is obtained based on the driver's braking intention and the normal vehicle speed.

[0049] If the electric motor brake fails, the IPB will control the hydraulic brake to supplement the braking force.

[0050] If the IPB system is determined to be normal in step S04, and the IPB system communication is determined to be normal in step S02, then step S05 is executed, the PDC executes the IPB braking feedback target torque, and the controller controls the IPB to perform normal braking.

[0051] If step S02 determines that the IPB system communication is abnormal, then step S06 is executed, and the controller executes the first abnormal control scheme under the IPB system communication abnormality.

[0052] If the IPB system is determined to be faulty in step S04, then step S07 is executed, and the controller executes the second abnormal control scheme corresponding to the IPB system failure.

[0053] The first abnormal control scheme includes: reducing the motor braking and increasing the hydraulic braking.

[0054] Optionally, motor braking can be reduced and hydraulic braking increased by attenuating the maximum permissible feedback capability.

[0055] Optionally, the maximum permissible feedback capability of the vehicle can be attenuated gradually or smoothly.

[0056] Optionally, the maximum permissible feedback capability of the vehicle can be attenuated gradually or smoothly. This allows for a gradual switch between electric motor braking and hydraulic braking, resulting in smoother vehicle braking and preventing vehicle jerking.

[0057] like Figure 3 As shown, optionally, in the first abnormal control scheme, the controller stops responding to the IPB braking feedback target torque.

[0058] Optionally, the first abnormal control scheme also includes switching to pure hydraulic braking. This ensures normal vehicle braking even when the IPB system communication is abnormal and unable to send feedback signals to the controller.

[0059] Optionally, the first abnormal control scheme further includes: when the vehicle's deceleration is less than the expected deceleration, controlling the IPB to increase the motor braking, wherein the expected deceleration is obtained based on the driver's deceleration intention and / or deceleration operation. In this way, when hydraulic braking is insufficient, appropriately increasing the motor braking compensation can better ensure braking performance.

[0060] Thus, this application incorporates communication anomalies as part of the braking system redundancy design. When an IPB experiences a communication anomaly, the maximum permissible feedback capability is gradually reduced, guiding the IPB to transition from electro-hydraulic coupling braking to pure hydraulic braking. Simultaneously, the vehicle deceleration is monitored in real time, and when the vehicle deceleration is significantly less than the expected deceleration, the motor regenerative braking force is promptly supplemented, thereby avoiding the risk of insufficient braking.

[0061] In the case of IPB failure, the corresponding second abnormal control scheme includes: controlling the motor to apply auxiliary braking torque based on the vehicle's real-time deceleration and required deceleration.

[0062] The auxiliary braking torque is less than or equal to the upper limit of torque, which is related to the vehicle's overall power generation capacity.

[0063] In some embodiments, in the second abnormal control scheme, the controller adjusts the target regenerative torque of the vehicle's motor to control the motor to be in a generating state, applying regenerative braking force, thereby affecting the vehicle's regenerative braking force and achieving deceleration control of the vehicle. Throughout the braking process, the controller continuously monitors the vehicle's deceleration to ensure that the vehicle is within a reasonable deceleration range when the IPB system fails, thus realizing the driver's braking intention.

[0064] In related technologies, the redundant design of vehicle braking systems does not monitor the acceleration during auxiliary braking, which poses a risk of over-braking or under-braking.

[0065] like Figure 4 This application obtains the required acceleration by measuring the brake push rod stroke and vehicle speed, and monitors the vehicle status and deceleration in real time. Through closed-loop control, it controls the motor to apply regenerative braking force to achieve the vehicle deceleration that meets the expected requirements.

[0066] In one optional embodiment, the second anomaly control scheme includes the following steps:

[0067] Step S071: Determine that the IPB system is malfunctioning and that the IPB is unable to apply hydraulic braking force.

[0068] Step S072: Obtain the preset deceleration based on the brake push rod travel and the vehicle speed. The greater the push rod travel and the higher the vehicle speed, the greater the preset deceleration value.

[0069] Step S073: Calculate the basic auxiliary braking torque based on the preset deceleration obtained in step S072;

[0070] Step S074: Compare the vehicle deceleration obtained in step S03 with the preset deceleration obtained in step S072, and find the auxiliary braking torque gain coefficient.

[0071] Step S075: Multiply the auxiliary braking torque gain coefficient calculated in step S074 and the basic auxiliary braking torque obtained in step S073 to obtain the target auxiliary braking torque.

[0072] Step S076: Control the motor braking according to the target auxiliary braking torque.

[0073] For step S073, the basic auxiliary braking torque will vary depending on the vehicle's overall parameters;

[0074] For step S074, in order to avoid excessive auxiliary braking torque, it is necessary to constrain the auxiliary braking torque gain coefficient. The upper limit of this coefficient can be calibrated according to the vehicle status.

[0075] For step S075, the calculated target auxiliary braking torque needs to be subject to torque limiting to prevent the torque from exceeding the vehicle's power generation capacity.

[0076] In this application, after recognizing the driver's braking intention, the controller checks whether the IPB-related messages are received normally, whether there is a fault, and whether the life frame is abnormal to determine if the IPB system is experiencing communication abnormalities. Simultaneously, the controller monitors the vehicle's deceleration in real time to determine if the IPB system has failed and whether it has the capability to apply hydraulic braking force. After determining whether the IPB system is experiencing communication abnormalities and failure, if both IPB system communication and the IPB system itself are normal, the controller executes the IPB braking feedback target torque normally, resulting in normal braking. If IPB system communication is normal but the IPB system is abnormal, the controller executes IPB system communication abnormality control (first abnormality control scheme). If both IPB system communication and the IPB system itself are abnormal, the controller executes IPB system abnormality control (second abnormality control scheme). Therefore, the braking system failure redundancy design control method of this application takes into account redundancy design control under both IPB system communication abnormality and IPB system failure modes, solving the problem of insufficient braking force or vehicle jerking caused by IPB system communication failure or system failure.

[0077] This application also provides a vehicle that includes a controller according to any of the above embodiments, or a braking control system according to any of the above embodiments.

Claims

1. A braking control method, characterized in that, include: In the event of an abnormality in the vehicle's braking system, an abnormal control scheme corresponding to the abnormal state of the braking system is executed; wherein, when the abnormal state is that the braking system is unable to send a feedback signal to the controller, the corresponding first abnormal control scheme includes reducing the electric motor braking and increasing the hydraulic braking.

2. The method according to claim 1, characterized in that, The first anomaly control scheme further includes: attenuating the maximum permissible feedback capability of the vehicle.

3. The method according to claim 2, characterized in that, The attenuation refers to the vehicle's maximum permissible feedback capability being either gradually attenuated or smoothly attenuated.

4. The method according to any one of claims 1-3, characterized in that, In the first anomaly control scheme: The electric motor braking is gradually reduced or smoothly reduced, while the hydraulic braking is gradually increased or smoothly increased.

5. The method according to any one of claims 1-4, characterized in that, The first anomaly control scheme also includes: Switch to pure hydraulic braking.

6. The method according to any one of claims 1-5, characterized in that, The first abnormal control scheme further includes: when the deceleration of the vehicle is less than the expected deceleration, controlling the braking system to increase the motor braking, wherein the expected deceleration is obtained based on the driver's deceleration intention and / or deceleration operation.

7. The method according to any one of claims 1-6, characterized in that, If the controller verifies that the life frame corresponding to the braking system is abnormal, the abnormal state is that the braking system is unable to send a feedback signal to the controller.

8. The method according to any one of claims 1-7, characterized in that, In the case of brake system failure, the corresponding second abnormal control scheme includes: controlling the motor to apply auxiliary braking torque based on the vehicle's real-time deceleration and required deceleration.

9. The method according to claim 8, characterized in that, In the event of hydraulic braking failure of the braking system, the abnormal state is a braking system failure.

10. The method according to claim 8, characterized in that, When the difference between the vehicle's real-time deceleration and the required deceleration exceeds a reasonable range, the hydraulic braking of the braking system fails.

11. The method according to any one of claims 8-10, characterized in that, The required deceleration is obtained based on the brake push rod travel and the vehicle speed, or the required acceleration is obtained based on the driver's braking intention and the normal vehicle speed.

12. The method according to any one of claims 8-11, characterized in that, The auxiliary braking torque is less than or equal to the upper limit of torque, which is related to the vehicle's overall power generation capacity.

13. A controller, characterized in that, The method includes a processor connected to a memory storing a computer program, the processor executing the computer program to implement the method according to any one of claims 1-12.

14. A braking control system, characterized in that, Includes a braking system and the controller as described in claim 13.

15. The braking control system according to claim 14, characterized in that, The controller is either a domain controller or a central controller.

16. A vehicle, characterized in that, Includes the controller as described in claim 13; Or it may include the braking control system as described in claim 14 or 15.

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