Vehicle and method, device for braking thereof

Abstract

This invention discloses a vehicle and its braking method and device. The vehicle includes a braking unit and a motor control unit. The method includes: when the regenerative braking function of the motor control unit is normal, if the motor control unit cannot determine whether the braking function of the braking unit has failed, it obtains the state of the brake light switch; if it determines that the brake light switch is in the on state, it controls braking based on regenerative torque through the motor control unit. Therefore, in cases where it is impossible to determine whether the braking unit has failed, the risk of accidents to passengers during vehicle operation is reduced, and the reliability of vehicle braking is improved.

Description

Technical Field

[0001] This application relates to the field of vehicles, specifically to a vehicle and its braking method and device. Background Technology

[0002] The growing severity of problems such as energy crisis, environmental pollution and greenhouse effect has made new energy vehicles, especially pure electric vehicles, an inevitable trend in the transformation of the automotive industry.

[0003] Pure electric vehicles use electric motors as their power source, and the motors can also convert the vehicle's kinetic energy into electrical energy for recycling, thereby achieving a deceleration and braking effect on the vehicle's movement. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, one objective of this invention is to provide a vehicle braking method in which the motor control unit, when unable to determine whether the braking function of the braking unit has failed and confirming that the brake light switch is in the on state, can perform feedback torque control braking based on vehicle speed, thereby reducing the risk of accidents to passengers during vehicle operation and improving the reliability of vehicle braking.

[0005] A second objective of this invention is to provide a computer-readable storage medium.

[0006] The third objective of this invention is to provide a vehicle.

[0007] According to an embodiment of the present invention, a vehicle braking method is applied to a vehicle, the vehicle including a braking unit, a motor control unit, and a brake light switch. The method includes: when the regenerative braking function of the motor control unit is normal, if the motor control unit cannot determine whether the braking function of the braking unit has failed, it obtains the state of the brake light switch; if it is determined that the state of the brake light switch is the on state, the motor control unit performs regenerative torque control braking based on the vehicle speed.

[0008] In some embodiments of the present invention, if the motor control unit does not receive a message sent by the braking unit within a first time period, or if the message sent by the braking unit is abnormal, it is determined that the braking unit cannot be judged as to whether it has failed.

[0009] In some embodiments of the present invention, when the braking function of the braking unit is normal, if the braking unit detects a target condition, it performs closed-loop control based on the target deceleration corresponding to the brake pedal depth; wherein, the target condition includes: it is impossible to determine whether the regenerative braking function of the motor control unit is effective, or the regenerative braking function of the motor control unit fails.

[0010] In some embodiments of the present invention, if the braking unit does not receive a message from the motor control unit within a second time period, or if the message sent by the motor control unit is abnormal, it is determined that the regenerative braking function of the motor control unit cannot be determined.

[0011] In some embodiments of the present invention, the braking unit includes dual braking circuits; normal braking function of the braking unit includes: both braking circuits are normal, or, a single braking circuit of the braking unit fails.

[0012] In some embodiments of the present invention, controlling vehicle braking includes: when both braking circuits are normal, performing closed-loop control based on a first target deceleration corresponding to a first brake pedal depth; when a single braking circuit of the braking unit fails, performing closed-loop control based on a second target deceleration corresponding to a second brake pedal depth; wherein, when the first brake pedal depth and the second brake pedal depth are the same, the second target deceleration is greater than the first target deceleration.

[0013] In some embodiments of the present invention, if the motor control unit determines that the vehicle will roll backward during the process of regenerative torque control braking based on vehicle speed, it stops performing regenerative torque control braking before the vehicle rolls backward.

[0014] If the braking unit determines that the vehicle will roll backward during closed-loop control based on the target deceleration corresponding to the brake pedal depth, it will stop performing closed-loop control before the vehicle rolls backward.

[0015] In some embodiments of the present invention, if the motor control unit determines that the braking unit has failed, it performs feedback torque control braking based on the maximum permissible feedback torque and the feedback torque sent by the braking unit.

[0016] According to an embodiment of the present invention, a computer-readable storage medium stores a vehicle braking program thereon, which, when executed by a processor, implements the vehicle braking method described above.

[0017] According to an embodiment of the present invention, a vehicle includes a memory, a processor, and a vehicle braking program stored in the memory and executable on the processor. When the processor executes the vehicle braking program, it implements the vehicle braking method described above.

[0018] According to an embodiment of the present invention, a vehicle includes: a braking unit, a motor control unit, and a brake light switch. The motor control unit is configured to: when the regenerative braking function of the motor control unit is normal, if it is determined that the braking function of the braking unit is not working, then obtain the state of the brake light switch; if it is determined that the state of the brake light switch is on, then perform regenerative torque control braking based on the vehicle speed.

[0019] In summary, this invention provides a vehicle braking method. When the regenerative braking function of the motor control unit is normal, the motor control unit can determine whether the braking function of the braking unit has failed. If it cannot determine whether the braking function of the braking unit has failed, it can determine the state of the brake light switch. If the brake light switch is in the on state, regenerative torque control braking is performed based on the vehicle speed. Therefore, even when it is impossible to determine whether the braking unit has failed, the risk of accidents to passengers during vehicle operation is reduced, and the reliability of vehicle braking is improved.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] Figure 1 This is a flowchart of a vehicle braking method provided in an embodiment of the present invention;

[0022] Figure 2 This is a flowchart of another vehicle braking method provided in an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of a vehicle structure provided in an embodiment of the present invention. Detailed Implementation

[0024] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0025] Figure 1 This is a flowchart of a vehicle braking method provided in an embodiment of the present invention. The method is applied to a vehicle, which may include: a braking unit, a motor control unit, and a brake light switch, such as... Figure 1 As shown, the method includes:

[0026] Step 101: If the regenerative braking function of the motor control unit is normal, and the motor control unit cannot determine whether the braking function of the braking unit has failed, then obtain the status of the brake light switch.

[0027] If the regenerative braking function of the motor control unit is normal, and the motor control unit cannot determine whether the braking function of the braking unit has failed, it can obtain the status of the brake light switch. The status of the brake light switch can be either on or off.

[0028] Optionally, if the motor control unit receives a brake start signal, it can determine that the brake light switch is in the on state.

[0029] Step 102: If the brake light switch is determined to be in the on state, the motor control unit performs feedback torque control braking based on the vehicle speed.

[0030] If the brake light switch is determined to be in the on state, the motor control unit will control the braking by providing feedback torque based on the vehicle speed.

[0031] In summary, this invention provides a vehicle braking method. When the regenerative braking function of the motor control unit is normal, the motor control unit can determine whether the braking function of the braking unit has failed. If it cannot determine whether the braking function of the braking unit has failed, it can determine the state of the brake light switch. If the brake light switch is in the on state, regenerative torque control braking is performed based on the vehicle speed. Therefore, even when it is impossible to determine whether the braking function of the braking unit has failed, the risk of accidents to passengers during vehicle operation can be reduced, and the reliability of vehicle braking can be improved.

[0032] Figure 2 This is a flowchart of another vehicle braking method provided in an embodiment of the present invention. This method is applied to vehicles, such as... Figure 2 As shown, the method may include:

[0033] Step 201: The motor control unit checks whether the regenerative braking function of the motor control unit is normal.

[0034] In this embodiment of the invention, the motor control unit can periodically or in real-time detect whether its regenerative braking function is normal. If the regenerative braking function of the motor control unit fails, the motor control unit can determine that it cannot control the vehicle braking, and therefore executes step 202. If the regenerative braking function of the motor control unit is normal, the motor control unit can determine that it can control the vehicle braking, and therefore sends a first valid prompt message to the braking unit and executes step 205. The first valid prompt message is used to indicate that the regenerative braking function of the motor control unit is normal.

[0035] Step 202: The motor control unit sends the first failure warning message to the braking unit.

[0036] If the motor control unit determines that the regenerative braking function of the motor control unit has failed, it can send a first failure warning message to the braking unit. This first failure warning message is used to indicate that the regenerative braking function of the motor control unit has failed.

[0037] Step 203: Check whether the braking function of the braking unit is normal.

[0038] The braking unit can periodically or in real-time check whether its braking function is normal. If the braking function of the braking unit fails, it can be determined that the braking unit cannot control the vehicle braking, and therefore step 204 is executed. If the braking function of the braking unit is normal, the braking unit can determine that it can control the vehicle braking, and therefore sends a second valid prompt message to the motor control unit and executes step 208. The second valid prompt message is used to indicate that the regenerative braking function of the braking unit is normal.

[0039] In this embodiment of the invention, the braking unit may include dual braking circuits. Normal braking function of the braking unit can include: both braking circuits being normal, or a single braking circuit of the braking unit failing, i.e., only one braking circuit failing. Failure of the braking function of the braking unit can include: both braking circuits failing.

[0040] Step 204: The braking unit sends a second failure warning message, a valid brake pedal indicator, and the feedback target torque corresponding to the brake pedal depth to the motor control unit.

[0041] If the braking unit determines that its braking function has failed, it can send a second failure warning message, a valid brake pedal indicator, and the target feedback torque corresponding to the brake pedal depth to the motor control unit. The second failure warning message is used to indicate that the braking function of the braking unit has failed.

[0042] Step 205: The motor control unit checks whether it can determine whether the braking function of the braking unit has failed.

[0043] If the motor control unit determines that its regenerative braking function is normal, it can check whether the braking function of the braking unit has failed. If it determines that the braking function of the braking unit has failed, the motor control unit can proceed to step 206. If it determines that the braking function of the braking unit has failed, the motor control unit can proceed to step 207.

[0044] In this embodiment of the invention, if the motor control unit does not receive a message from the braking unit within a first time period, it can determine whether the braking function of the braking unit has failed. The first time period can be pre-stored in the motor control unit. Alternatively, if the motor control unit determines that the received message from the braking unit is abnormal, it can determine whether the braking function of the braking unit has failed.

[0045] Understandably, regardless of whether the braking function of the braking unit is normal, if the controller area network (CAN) fails, the motor control unit will be unable to receive the message sent by the braking unit. As a result, the motor control unit cannot determine whether the braking function of the braking unit has failed. This message can be a CAN message.

[0046] If the motor control unit receives a second failure warning message, it can determine that the braking function of the braking unit has failed. In this case, the CAN bus will function normally. If it receives a second valid warning message, it can determine that the braking function of the braking unit is valid. In this case, the CAN bus will also function normally.

[0047] Step 206: The motor control unit obtains the status of the brake light switch. If the brake light switch is in the on state, the control unit performs feedback torque control braking based on the vehicle speed.

[0048] If the regenerative braking function of the motor control unit is normal, and the motor control unit cannot determine whether the braking function of the braking unit has failed, it can obtain the status of the brake light switch, which can be either on or off. If the brake light switch is on, regenerative torque control braking can be performed based on vehicle speed. If the brake light switch is off, there is no need to control the vehicle braking.

[0049] If the motor control unit receives a brake start signal, it can determine that the brake light switch is in the on state. For example, when the driver presses the brake pedal, the motor control unit can receive the brake start signal and thus determine that the brake light switch is in the on state. When the driver does not press the brake pedal, the brake light switch is in the off state.

[0050] The motor control unit can pre-store the correspondence between vehicle speed and torque. Based on the current vehicle speed, the motor control unit can determine the torque corresponding to the current vehicle speed from the correspondence, and control the motor based on the determined torque, thereby realizing regenerative torque control braking.

[0051] In this embodiment of the invention, if the motor control unit determines that the vehicle will roll backward during the process of regenerative torque control braking based on vehicle speed, it can stop the regenerative torque control braking before the vehicle rolls backward, thereby preventing the vehicle from accelerating backward.

[0052] Furthermore, if the motor control unit determines that the vehicle's rotational speed is less than the preset speed and the rate at which the rotational speed decreases is greater than the preset rate, it can determine that the vehicle will roll backward.

[0053] In this embodiment of the invention, the motor control unit can control the vehicle to complete braking before the vehicle rolls backward, thereby preventing backward rolling and maximizing the use of torque braking.

[0054] Step 207: When the motor control unit determines that the braking unit has failed, it performs feedback torque control braking based on the maximum permissible feedback torque and the feedback target torque sent by the braking unit.

[0055] When the motor control unit determines that the braking function of the braking unit has failed, it can determine the maximum permissible feedback torque and perform feedback torque control braking based on the maximum permissible feedback torque and the feedback target torque sent by the braking unit.

[0056] The motor control unit can calculate the maximum permissible feedback torque in real time. After receiving the second failure warning information sent by the braking unit, the motor control unit can request the maximum permissible charging power of the battery from the battery management system (BMS) and obtain the efficiency and speed of the motor. Based on the maximum permissible charging power, the efficiency and speed of the motor, the maximum permissible feedback torque is determined.

[0057] The maximum permissible regenerative torque N can satisfy: P is the maximum allowable charging power, n is the motor speed, E is the motor efficiency, and K is a constant.

[0058] During the regenerative torque control braking process based on the maximum permissible regenerative torque and the target regenerative torque sent by the braking unit, if the motor control unit receives a vehicle rollback command from the braking unit, it can determine that the vehicle will rollback. Therefore, it can stop the regenerative torque control braking before the vehicle rolls back, thereby controlling the vehicle to stop braking.

[0059] The vehicle rollback command includes a target torque value, which is 0. The motor control unit can determine whether the vehicle will roll backward based on the target torque value sent by the braking unit. If the target torque value is 0, then it can be determined that the vehicle will roll backward.

[0060] Optionally, the braking unit can determine whether the vehicle will roll backward based on the current wheel speed, direction, and gear. If it is determined that the vehicle will roll backward, it can send a feedback target torque value to the motor control unit before the vehicle rolls backward, thereby causing the motor control unit to stop performing feedback torque control braking before the vehicle rolls backward.

[0061] The motor control unit can perform feedback torque control braking before the vehicle rolls backward, thus preventing backward rolling and maximizing the use of torque braking.

[0062] Step 208: The braking unit determines whether the target condition has been detected.

[0063] If the braking unit determines that its braking function is normal, it can determine whether a target condition has been detected. If a target condition is detected, the braking unit can execute step 209. The target condition may include: it is impossible to determine whether the regenerative braking function of the motor control unit is effective, or the regenerative braking function of the motor control unit is malfunctioning.

[0064] If the target condition is not detected, the braking unit can determine that the motor control unit is normal and the CAN is normal, so step 210 can be executed.

[0065] In this embodiment of the invention, if the braking unit does not receive a message from the motor control unit within a second time period, it can determine whether the regenerative braking function of the motor control unit is effective. The braking unit may pre-store the second time period. Alternatively, if the braking unit determines that the message sent by the motor control unit is abnormal, it can detect that it cannot determine whether the regenerative braking function of the motor control unit is effective.

[0066] Understandably, regardless of whether the regenerative braking function of the motor control unit is normal, a CAN failure will prevent the braking unit from receiving messages sent by the motor control unit, thus making it impossible for the braking unit to determine whether the regenerative braking function of the motor control unit is effective.

[0067] If the braking unit receives the first failure warning message, it can determine that the regenerative braking function of the motor control unit has failed, and thus determine that the target condition has been detected. In this case, CAN is normal. If it receives the first valid warning message, it can determine that the regenerative braking function of the motor control unit is valid, and thus determine that the target condition has not been detected. In this case, CAN is normal.

[0068] Step 209: Perform closed-loop control based on the target deceleration corresponding to the brake pedal depth.

[0069] Under certain target conditions, the braking unit can perform closed-loop control based on the target deceleration corresponding to the brake pedal depth.

[0070] Optionally, when both braking circuits are functioning normally, the braking unit can perform closed-loop control based on the first target deceleration corresponding to the first brake pedal depth. If one braking circuit of the braking unit fails, the braking unit can perform closed-loop control based on the second target deceleration corresponding to the second brake pedal depth.

[0071] Among them, when the first brake pedal depth and the second brake pedal depth are the same, the deceleration of the second target is greater than that of the first target.

[0072] The braking unit can pre-store the correspondence between pedal depth and target deceleration. Based on the first brake pedal depth, the braking unit can determine the first target deceleration corresponding to the first brake pedal depth from the correspondence, and perform closed-loop control based on the first target deceleration.

[0073] If the braking unit determines that the vehicle will roll backward during the braking process, it can control the vehicle to perform closed-loop control before the vehicle rolls backward.

[0074] Optionally, the braking unit can control the vehicle to complete braking before it rolls backward, thereby preventing it from rolling backward and maximizing the use of torque braking.

[0075] Step 210: The braking unit and the motor control unit jointly control the vehicle braking.

[0076] If the braking unit does not detect the target condition, it can be determined that the regenerative braking function of the motor control unit is normal. Therefore, the braking unit and the motor control unit jointly control the vehicle braking.

[0077] If the motor control unit can determine that the braking function of the braking unit is normal, then the braking unit and the motor control unit jointly control the vehicle braking. The braking unit and the motor control unit can execute the function of regenerative braking systems (RBS), that is, superimposing the reverse torque of the motor's energy recovery function on the braking force of the mechanical hydraulic braking system.

[0078] In the event that both the braking unit and the motor control unit fail, braking can only be achieved by the driver pressing the brake pedal with their foot to build up mechanical pressure without assistance.

[0079] In this embodiment of the invention, when the braking unit fails, some components of the vehicle's motor will fail and become inoperable during the pressure build-up process. However, the brake pedal can still drive the vehicle's master cylinder to work. At this time, the master cylinder can provide some mechanical braking force, thereby controlling the vehicle's braking.

[0080] In summary, this invention provides a vehicle braking method. When the regenerative braking function of the motor control unit is normal, the motor control unit can determine whether the braking function of the braking unit has failed. If it cannot determine whether the braking function of the braking unit has failed, it can determine the state of the brake light switch. If the brake light switch is in the on state, regenerative torque control braking is performed based on the vehicle speed. Therefore, even when it is impossible to determine whether the braking unit has failed, the risk of accidents to passengers during vehicle operation is reduced, and the reliability of vehicle braking is improved.

[0081] Furthermore, the motor control unit can determine the effectiveness of its regenerative braking function and the braking function of the braking unit, or the braking unit can determine the effectiveness of its braking function and the regenerative braking function of the motor control unit, and brake the vehicle in different ways depending on the situation. Because this invention fully considers all possible scenarios that may occur when the braking function fails, and brakes the vehicle in different ways depending on the situation, the risk of accidents to passengers during travel can be reduced, and the safety and reliability of the vehicle can be improved.

[0082] This invention provides a computer-readable storage medium storing a vehicle braking program, which, when executed by a processor, implements the vehicle braking method described in the above embodiments. For example, Figure 1 or Figure 2 The vehicle braking method shown.

[0083] Figure 3 This is a structural schematic diagram of a vehicle provided in an embodiment of the present invention, such as... Figure 3 As shown, vehicle 30 may include memory 301, processor 302, and a vehicle braking program stored in memory 301 and executable on processor 302. When processor 302 executes the vehicle braking program, it implements the vehicle braking method shown in the above embodiment. For example, Figure 1 or Figure 2 The vehicle braking method shown.

[0084] According to an embodiment of the present invention, a vehicle is provided, comprising: a braking unit and a motor control unit, wherein the motor control unit is configured to:

[0085] If the regenerative braking function of the motor control unit is normal, and it is detected that the braking function of the braking unit cannot be determined, then the status of the brake light switch in the braking unit is obtained.

[0086] If the brake light switch is determined to be in the on state, the motor control unit will control the braking by providing feedback torque based on the vehicle speed.

[0087] Optionally, the motor control unit is also configured to: if it does not receive a message from the braking unit within a first time period, or if the message sent by the braking unit is abnormal, determine that it is impossible to determine whether the braking unit has failed.

[0088] Optionally, the braking unit is used to: when the braking function of the braking unit is normal, if the target condition is determined, perform closed-loop control based on the target deceleration corresponding to the brake pedal depth.

[0089] The target conditions include: it is impossible to determine whether the regenerative braking function of the motor control unit is effective, or the regenerative braking function of the motor control unit is ineffective.

[0090] Optionally, the braking unit is also configured to: determine whether the regenerative braking function of the motor control unit is effective if no message is received from the motor control unit within the second time period; or if the message sent by the motor control unit is abnormal.

[0091] Optionally, the braking unit includes dual braking circuits; normal braking unit operation includes: both braking circuits being normal, or, a single braking circuit of the braking unit failing.

[0092] Optionally, the braking unit is used to: perform closed-loop control based on a first target deceleration corresponding to the first brake pedal depth when both braking circuits are normal; and perform closed-loop control based on a second target deceleration corresponding to the second brake pedal depth when a single braking circuit of the braking unit fails; wherein, when the first brake pedal depth and the second brake pedal depth are the same, the second target deceleration is greater than the first target deceleration.

[0093] Optionally, the motor control unit is also used to stop the regenerative torque control braking before the vehicle rolls backward if it is determined that the vehicle will roll backward during the process of regenerative torque control braking based on vehicle speed.

[0094] The braking unit is also used to stop performing closed-loop control before the vehicle rolls backward if it is determined that the vehicle will roll backward during the closed-loop control process based on the target deceleration corresponding to the brake pedal depth.

[0095] Optionally, the motor control unit is also configured to: if the braking unit is determined to have failed, perform regenerative torque control braking based on the maximum permissible regenerative torque and the regenerative torque sent by the braking unit.

[0096] In summary, this invention provides a vehicle braking method. When the regenerative braking function of the motor control unit is normal, the motor control unit can determine whether the braking function of the braking unit has failed. If it cannot determine whether the braking function of the braking unit has failed, it can determine the state of the brake light switch. If the brake light switch is in the on state, regenerative torque control braking is performed based on the vehicle speed. Therefore, even when it is impossible to determine whether the braking unit has failed, the risk of accidents to passengers during vehicle operation is reduced, and the reliability of vehicle braking is improved.

[0097] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0098] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0099] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0100] Furthermore, the terms "first," "second," etc., used in the embodiments of this invention are for descriptive purposes only and should not be construed as indicating or implying relative importance, or implicitly specifying the number of technical features indicated in this embodiment. Therefore, features defined with terms such as "first" and "second" in the embodiments of this invention can explicitly or implicitly indicate that the embodiment includes at least one of those features. In the description of this invention, the word "multiple" means at least two or more, such as two, three, four, etc., unless otherwise explicitly specified in the embodiments.

[0101] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A vehicle braking method, characterized in that, Applied to a vehicle, the vehicle including: a braking unit, a motor control unit, and a brake light switch, the method includes: If the regenerative braking function of the motor control unit is normal, and the motor control unit cannot determine whether the braking function of the braking unit has failed, then it obtains the status of the brake light switch. If the brake light switch is determined to be in the on state, the motor control unit performs feedback torque control braking based on the vehicle speed. If the motor control unit does not receive a message from the braking unit within a first time period, or if the message sent by the braking unit is abnormal, it is determined that it cannot determine whether the braking unit has failed. The motor control unit detects whether the regenerative braking function of the motor control unit is normal; If so, a first valid prompt message is sent to the braking unit, the first valid prompt message being used to indicate that the regenerative braking function of the motor control unit is normal; If not, the motor control unit sends a first failure warning message to the braking unit, the first failure warning message being used to indicate that the regenerative braking function of the motor control unit has failed; The motor control unit can determine whether the braking function of the braking unit has failed. If so, then feedback torque control braking is performed based on the maximum permissible feedback torque and the feedback target torque sent by the braking unit; If not, the motor control unit obtains the status of the brake light switch. If the brake light switch is in the on state, then the regenerative torque control braking is performed based on the vehicle speed.

2. The method according to claim 1, characterized in that, The method further includes: When the braking function of the braking unit is normal, if the braking unit determines the target condition, it will perform closed-loop control based on the target deceleration corresponding to the brake pedal depth. The target conditions include: it is impossible to determine whether the regenerative braking function of the motor control unit is effective, or the regenerative braking function of the motor control unit is ineffective.

3. The method according to claim 2, characterized in that, The method further includes: If the braking unit does not receive a message from the motor control unit within the second time period, or if the message sent by the motor control unit is abnormal, it is determined that the regenerative braking function of the motor control unit cannot be effective.

4. The method according to claim 2, characterized in that, The braking unit includes dual braking circuits; The braking function of the braking unit is normal if both braking circuits are normal, or if one braking circuit of the braking unit fails.

5. The method according to claim 4, characterized in that, Closed-loop control is performed based on the target deceleration corresponding to the brake pedal depth, including: Under the condition that both braking circuits are normal, closed-loop control is performed based on the first target deceleration corresponding to the first brake pedal depth. In the event of failure of a single braking circuit in the braking unit, closed-loop control is performed based on the second target deceleration corresponding to the second brake pedal depth. Where the first brake pedal depth and the second brake pedal depth are the same, the second target deceleration is greater than the first target deceleration.

6. The method according to claim 2, characterized in that, The method further includes: If the motor control unit determines that the vehicle will roll backward during the regenerative torque control braking process based on vehicle speed, it will stop the regenerative torque control braking before the vehicle rolls backward. If the braking unit determines that the vehicle will roll backward during closed-loop control based on the target deceleration corresponding to the brake pedal depth, it will stop performing closed-loop control before the vehicle rolls backward.

7. The method according to any one of claims 1 to 5, characterized in that, The method further includes: If the motor control unit determines that the braking unit has failed, it performs feedback torque control braking based on the maximum permissible feedback torque and the feedback torque sent by the braking unit.

8. A computer-readable storage medium, characterized in that, It stores a vehicle braking program, which, when executed by a processor, implements the vehicle braking method according to any one of claims 1 to 7.

9. A vehicle, characterized in that, The system includes a memory, a processor, and a vehicle braking program stored in the memory and executable on the processor. When the processor executes the vehicle braking program, it implements the vehicle braking method according to any one of claims 1 to 7.

10. A vehicle, characterized in that, The vehicle includes: a braking unit, a motor control unit, and a brake light switch. The motor control unit is used for: If the regenerative braking function of the motor control unit is normal, and it cannot be determined whether the braking function of the braking unit has failed, then the state of the brake light switch is obtained. If the brake light switch is determined to be in the on state, then feedback torque control braking is performed based on the vehicle speed; If the motor control unit does not receive a message from the braking unit within a first time period, or if the message sent by the braking unit is abnormal, it is determined that it cannot determine whether the braking unit has failed. The motor control unit detects whether the regenerative braking function of the motor control unit is normal; If so, a first valid prompt message is sent to the braking unit, the first valid prompt message being used to indicate that the regenerative braking function of the motor control unit is normal; If not, the motor control unit sends a first failure warning message to the braking unit, the first failure warning message being used to indicate that the regenerative braking function of the motor control unit has failed; The motor control unit can determine whether the braking function of the braking unit has failed. If so, then feedback torque control braking is performed based on the maximum permissible feedback torque and the feedback target torque sent by the braking unit; If not, the motor control unit obtains the status of the brake light switch. If the brake light switch is in the on state, then the regenerative torque control braking is performed based on the vehicle speed.

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