Power-off self-test method and vehicle

Abstract

An embodiment of the present invention provides a power-off self-inspection method and a vehicle, which relate to the field of vehicle braking. The method includes starting timing when it is detected that the electronic hydraulic brake system is in a power-off state of the entire vehicle, and when the power-off state of the entire vehicle lasts for a preset time, and the brake pedal of the vehicle is not stepped on, the vehicle speed is zero, and the parking system of the vehicle is in a parking state, determining the self-inspection strategy of each component in the electronic hydraulic brake system, thereby ensuring that the electronic hydraulic brake system can work normally when it is started next time, thereby ensuring driving safety, thereby ensuring that the electronic hydraulic brake system can work normally when it is started next time, thereby ensuring driving safety.

Description

Technical Field

[0001] The present invention relates to the field of vehicle braking, and in particular to a power-off self-checking method and a vehicle. Background Art

[0002] The integrated electronic hydraulic braking system includes the functions of three major braking products: EHB (Electronic Hydraulic Brake), EPB (Electronic Park Brake), and ESC (Electronic Stability Control). It can achieve high-quality basic braking, wire-controlled braking, wire-controlled parking, stability control and other functions, and can serve as a chassis domain controller to fully take over the wire-controlled chassis.

[0003] However, since multiple braking functions of the integrated electronic hydraulic brake system share one controller, when some functions fail, the system can only rely on mechanical backup for braking. Therefore, it is necessary for the integrated electronic hydraulic brake system to perform self-checks for each function before operation.

[0004] The strategy of power-off detection in the integrated electronic hydraulic brake system is even more important. Power-off detection is a series of detection or self-test processes performed when the vehicle power is turned off or the vehicle is in a non-operating state. These tests are designed to ensure that the various systems of the vehicle can work normally when they are started next time, and can help identify potential problems.

[0005] Therefore, there is an urgent need for a power-off self-check method to perform a self-check on the electronic hydraulic brake system when the power is off to ensure driving safety. Summary of the invention

[0006] The object of the present invention is to provide a power-off self-inspection method and a vehicle, which can perform power-off self-inspection on an electronic hydraulic brake system to ensure driving safety.

[0007] In order to achieve the above purpose, the technical solution adopted by the embodiment of the present invention is as follows:

[0008] In a first aspect, an embodiment of the present invention provides a power-off self-test method, which is applied to a vehicle controller, wherein the vehicle controller is communicatively connected to an electronic hydraulic brake system of the vehicle, and the method comprises:

[0009] The timing starts when it is detected that the electronic hydraulic brake system is in the vehicle power-off state;

[0010] When the duration of the power-off state of the whole vehicle reaches a preset time, the brake pedal of the vehicle is not stepped on, the vehicle speed is zero, and the parking system of the vehicle is in the parking state, determining the self-check strategy of each component in the electronic hydraulic brake system;

[0011] Each component in the electronic hydraulic brake system is tested separately according to the self-test strategy to complete the power-off self-test.

[0012] Optionally, each component in the electronic hydraulic brake system includes an electric cylinder, a master cylinder and a solenoid valve group, the vehicle controller is in communication connection with the electric cylinder, the master cylinder and the solenoid valve group, and the step of testing each component in the electronic hydraulic brake system according to the self-test strategy to complete the power-off self-test includes:

[0013] Controlling the electric cylinder to establish a first preset pressure;

[0014] Based on the first preset pressure, the power-on state of the solenoid valve group is controlled to complete the power-off self-test.

[0015] Optionally, the solenoid valve group includes a PSV1 valve and a PSV2 valve, and the step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test includes:

[0016] Switch the PSV1 valve and the PSV2 valve to a power-off state;

[0017] Detecting the real-time pressure of the master cylinder and the real-time pressure of the electric cylinder;

[0018] Based on the real-time pressure of the master cylinder, the first preset pressure, and the real-time pressure of the electric cylinder, the working states of the electric cylinder, the PSV1 valve, and the PSV2 valve are determined.

[0019] Optionally, the solenoid valve group includes a PSV1 valve, an IV1 valve, an IV2 valve, an IV3 valve, an IV4 valve, a CSV1 valve and a CSV2 valve, the CSV1 valve is respectively connected to the IV1 valve and the IV2 valve through an oil circuit, the CSV2 valve is respectively connected to the IV3 valve and the IV4 valve through an oil circuit, and the step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test includes:

[0020] Controlling the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve to be in an energized state;

[0021] Control the PSV1 valve to be energized;

[0022] Detecting the real-time pressure of the electric cylinder;

[0023] Based on the real-time pressure of the electric cylinder and the first preset pressure, the working states of the CSV1 valve, the IV1 valve and the IV2 valve are determined.

[0024] Optionally, the solenoid valve group further includes an OV1 valve, the OV1 valve is connected to the IV1 valve, and the step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test also includes:

[0025] Controlling the IV1 valve to a power-off state;

[0026] Detecting the real-time pressure of the electric cylinder;

[0027] Determine the working states of the OV1 valve, the IV1 valve, the wheel end corresponding to the IV1 valve, and the wheel end pipeline corresponding to the IV1 valve based on the real-time pressure of the electric cylinder and the first preset pressure;

[0028] Controlling the OV1 valve to be energized;

[0029] Detecting the real-time pressure of the electric cylinder;

[0030] The working state of the OV1 valve is determined based on the real-time pressure of the electric cylinder and the first preset pressure.

[0031] Optionally, the solenoid valve group further includes an OV2 valve, the OV2 valve is connected to the IV2 valve, and the step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test also includes:

[0032] Controlling the OV1 valve and the IV2 valve to be in a power-off state;

[0033] Detecting the real-time pressure of the electric cylinder;

[0034] Based on the real-time pressure of the electric cylinder and the first preset pressure, determining the working states of the IV2 valve, the OV2 valve, the wheel end corresponding to the IV2 valve, and the wheel end pipeline corresponding to the IV2 valve;

[0035] Controlling the OV2 valve to be in an energized state;

[0036] Detecting the real-time pressure of the electric cylinder;

[0037] The working state of the OV2 valve is determined based on the real-time pressure of the electric cylinder and the first preset pressure.

[0038] Optionally, the solenoid valve group includes a PSV2 valve, an IV1 valve, an IV2 valve, an IV3 valve, an IV4 valve, a CSV1 valve and a CSV2 valve, the CSV1 valve is respectively connected to the IV1 valve and the IV2 valve through an oil circuit, the CSV2 valve is respectively connected to the IV3 valve and the IV4 valve through an oil circuit, and the step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test includes:

[0039] Controlling the CSV1 valve, CSV2 valve, IV3 valve, IV4 valve and PSV2 valve to be energized;

[0040] Detecting the real-time pressure of the electric cylinder;

[0041] Based on the real-time pressure of the electric cylinder and the first preset pressure, the working states of the CSV2 valve, the IV3 valve and the IV4 valve are determined.

[0042] Optionally, the solenoid valve group further includes an OV3 valve and an OV4 valve, the OV3 valve is connected to the IV3 valve, the OV4 valve is connected to the IV4 valve, and the step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test also includes:

[0043] Controlling the IV3 valve to a power-off state;

[0044] Detecting the real-time pressure of the electric cylinder;

[0045] Determine the working states of the IV3 valve, the OV3 valve, the wheel end corresponding to the IV3 valve, and the pipeline of the wheel end corresponding to the IV3 valve based on the real-time pressure of the electric cylinder and the first preset pressure;

[0046] Controlling the OV3 valve to be in an energized state;

[0047] Detecting the real-time pressure of the electric cylinder;

[0048] Determining the working state of the OV3 valve based on the real-time pressure of the electric cylinder and the first preset pressure;

[0049] Controlling the OV3 valve and the IV4 valve to be in a power-off state;

[0050] Detecting the real-time pressure of the electric cylinder;

[0051] Determine the working states of the IV4 valve, the OV4 valve, the wheel end corresponding to the IV4 valve, and the pipeline of the wheel end corresponding to the IV4 valve based on the real-time pressure of the electric cylinder and the first preset pressure;

[0052] Controlling the OV4 valve to be in an energized state;

[0053] Detecting the real-time pressure of the electric cylinder;

[0054] The working state of the OV4 valve is determined based on the real-time pressure of the electric cylinder and the first preset pressure.

[0055] Optionally, the solenoid valve group includes a PSV1 valve, a PSV2 valve, a TSV valve, a CSV1 valve, a CSV2 valve and an SSV valve, the SSV valve is connected to the master cylinder, the TSV valve is connected to the master cylinder, the CSV1 valve is respectively connected to the IV1 valve and the IV2 valve through an oil circuit, the CSV2 valve is respectively connected to the IV3 valve and the IV4 valve through an oil circuit, and the step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test includes:

[0056] Controlling the PSV1 valve and the PSV2 valve to be energized;

[0057] Detecting the real-time pressure of the electric cylinder;

[0058] Determining the working states of the CSV1 valve, the CSV2 valve, the TSV valve, and the SSV valve based on the real-time pressure of the electric cylinder and the first preset pressure;

[0059] Detecting the real-time pressure of the master cylinder;

[0060] Determining the working states of the pressure sensor of the master cylinder and the pressure sensor of the electric cylinder based on the real-time pressure of the master cylinder and the real-time pressure of the electric cylinder;

[0061] Controlling the SSV valve to be in an energized state;

[0062] Detecting the real-time pressure of the electric cylinder;

[0063] The working state of the SSV valve is determined based on the real-time pressure of the electric cylinder and the first preset pressure.

[0064] In a second aspect, an embodiment of the present invention provides a vehicle, including a processor and a memory, wherein the memory stores a computer program that can be executed by the processor, and the processor can execute the computer program to implement the power-off self-test method.

[0065] The present invention has the following beneficial effects:

[0066] The vehicle controller starts timing when it detects that the electronic hydraulic brake system is in the power-off state of the vehicle. When the power-off state of the vehicle lasts for a preset time, the vehicle's brake pedal is not stepped on, the vehicle speed is zero, and the vehicle's parking system is in the parking state, the self-check strategy of each component in the electronic hydraulic brake system is determined to ensure that the electronic hydraulic brake system can work normally when it is started next time, thereby ensuring driving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0068] Figure 1 A schematic diagram of an electronic hydraulic brake system provided by an embodiment of the present invention;

[0069] Figure 2 A block diagram of a vehicle controller provided by an embodiment of the present invention;

[0070] Figure 3 One of the flowcharts of a power-off self-test method provided by an embodiment of the present invention;

[0071] Figure 4 A second flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0072] Figure 5 A third flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0073] Figure 6 One of the state switching schematic diagrams of the electronic hydraulic brake system provided by an embodiment of the present invention;

[0074] Figure 7 A fourth flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0075] Figure 8 A second schematic diagram of state switching of an electronic hydraulic brake system provided by an embodiment of the present invention;

[0076] Fig. 9 A fifth flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0077] Fig.10 A third state switching diagram of the electronic hydraulic brake system provided by an embodiment of the present invention;

[0078] Fig.11 A fourth state switching diagram of the electronic hydraulic brake system provided in an embodiment of the present invention;

[0079] Fig.12 A sixth flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0080] Fig.13 A fifth state switching diagram of the electronic hydraulic brake system provided in an embodiment of the present invention;

[0081] Fig.14 A sixth state switching diagram of the electronic hydraulic brake system provided in an embodiment of the present invention;

[0082] Fig.15 A seventh flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0083] Fig.16 A seventh state switching diagram of an electronic hydraulic brake system provided in an embodiment of the present invention;

[0084] Fig.17 An eighth flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0085] Fig.18 An eighth state switching diagram of the electronic hydraulic brake system provided by an embodiment of the present invention;

[0086] Fig.19 A ninth state switching diagram of an electronic hydraulic brake system provided in an embodiment of the present invention;

[0087] Fig. 20 A tenth schematic diagram of state switching of an electronic hydraulic brake system provided in an embodiment of the present invention;

[0088] Fig.21 The eleventh state switching diagram of the electronic hydraulic brake system provided by the embodiment of the present invention;

[0089] Fig. 22 A ninth flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0090] Fig.23 A twelfth schematic diagram of state switching of an electronic hydraulic brake system provided in an embodiment of the present invention;

[0091] Fig.24 The thirteenth state switching diagram of the electronic hydraulic brake system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0092] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0093] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0094] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0095] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear to indicate an orientation or position relationship, they are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the invention is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0096] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0097] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0098] The integrated electronic hydraulic braking system includes the functions of three major braking products: EHB (Electronic Hydraulic Brake), EPB (Electronic Park Brake), and ESC (Electronic Stability Control). It can achieve high-quality basic braking, wire-controlled braking, wire-controlled parking, stability control and other functions, and can serve as a chassis domain controller to fully take over the wire-controlled chassis.

[0099] like Figure 1As shown, it is a schematic diagram of an electronic hydraulic brake system, which includes an oil pot module 10, a wheel end module 20, a main brake circuit 30 and a mechanical brake circuit 40. The oil pot module includes a small oil pot 11 and a large oil pot 12. The main brake circuit 30 includes an electric cylinder 31 and a PSV1 valve and a PSV2 valve. The pressure buildup of the electric cylinder 31 is achieved by the piston movement in the electric cylinder driven by the motor. The wheel end module 20 includes an IV1 valve, an IV2 valve, an IV3 valve, an IV4 valve, an OV1 valve, an OV2 valve, an OV3 valve and an OV4 valve. The IV1 valve is connected to the OV1 valve, the OV1 valve is connected to the first wheel end, the IV2 valve is connected to the OV2 valve, and the OV2 valve is connected to the second wheel end. The IV3 valve is connected to the OV3 valve, the OV3 valve is connected to the third wheel end, the IV4 valve is connected to the OV4 valve, and the OV4 valve is connected to the fourth wheel end. The PSV1 valve of the main brake circuit 30 is connected to the IV1 valve and the IV2 valve through an oil circuit, and the PSV2 valve of the main brake circuit 30 is connected to the IV3 valve and the IV4 valve through an oil circuit. When the solenoid valve in the mechanical brake circuit 40 is in a closed state and the PSV1 valve and the PSV2 valve are in an energized state, the electric cylinder 31 provides hydraulic pressure to the IV1 valve, the IV2 valve, the IV3 valve and the IV4 valve.

[0100] The mechanical brake circuit 40 includes a master cylinder 41, a CSV1 valve, a CSV2 valve, an SSV valve and a TSV valve. The CSV1 valve, the CSV2 valve, the SSV valve and the TSV valve are respectively connected to the master cylinder. The SSV valve is connected to the simulation chamber 42. The simulation chamber 42 is connected to the oil pot module 10 through an oil circuit. The other end of the TSV valve is connected to the oil pot module 10. The CSV1 valve is connected to the IV1 valve and the IV2 valve through an oil circuit. The CSV2 valve is connected to the IV3 valve and the IV4 valve through an oil circuit. When the CSV1 valve and the CSV2 valve are in a power-off state, that is, the CSV1 valve and the CSV2 valve allow flow to pass through, and the PSV1 valve and the PSV2 valve are in a power-off state, that is, the PSV1 valve and the PSV2 valve do not allow flow to pass through, the master cylinder 41 provides hydraulic pressure to the IV1 valve, the IV2 valve, the IV3 valve and the IV4 valve. The master cylinder 41 is connected to the brake pedal 43, and pressure is built up in the master cylinder 41 by stepping on the brake pedal 43.

[0101] It should be noted that the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve are normally open valves, that is, when the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve are powered on, the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve are powered on, that is, the flow is not allowed to pass through, and when the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve are powered off, the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve are powered off, that is, the flow is allowed to pass through. In the electronic hydraulic brake system, other solenoid valves except the above-mentioned CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve are normally closed valves.

[0102] Therefore, there is an urgent need to provide a power-off self-check method to perform self-check on the electronic hydraulic brake system when the power is off to ensure driving safety.

[0103] In view of the discovery of the above problems, the present embodiment provides a power-off self-check method and a vehicle, which can start timing when the vehicle controller detects that the electronic hydraulic brake system is in the power-off state of the whole vehicle. When the power-off state of the whole vehicle lasts for a preset time, and the brake pedal of the vehicle is not stepped on, the vehicle speed is zero, and the parking system of the vehicle is in the parking state, the self-check strategy of each component in the electronic hydraulic brake system is determined to ensure that the electronic hydraulic brake system can work normally when it is started next time, so as to ensure driving safety. The solution provided in this embodiment is elaborated in detail below.

[0104] This embodiment provides a vehicle controller that can perform power-off self-test on an electronic hydraulic brake system. In a possible implementation, the vehicle controller can be, but is not limited to, a vehicle computer, a server, a smart phone, a personal computer (PC), a tablet computer, a personal digital assistant (PDA), a mobile Internet device (MID), etc.

[0105] Please refer to Figure 2 , Figure 2 FIG. 1 is a schematic diagram of the structure of a vehicle controller 100 provided in an embodiment of the present invention. The vehicle controller 100 may also include Figure 2 More or fewer components as shown, or with Figure 2 Different configurations are shown. Figure 2 Each component shown in the figure can be implemented by hardware, software or a combination thereof.

[0106] The vehicle controller 100 includes a power-off self-test device 110 , a memory 120 and a processor 130 .

[0107] The components of the memory 120 and the processor 130 are electrically connected to each other directly or indirectly to realize data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The power-off self-test device 110 includes at least one software function module that can be stored in the memory 120 in the form of software or firmware or solidified in the operating system (OS) of the vehicle controller 100. The processor 130 is used to execute the executable modules stored in the memory 120, such as the software function modules and computer programs included in the power-off self-test device 110.

[0108] The memory 120 may be, but is not limited to, a random access memory (RAM), a read only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable read-only memory (EEPROM), etc. The memory 120 is used to store a program, and the processor 130 executes the program after receiving an execution instruction.

[0109] Please refer to Figure 3 , Figure 2 For application Figure 2 A flow chart of a power-off self-test method of a vehicle controller 100 is shown, and the method including each step is described in detail below.

[0110] S201: Start timing when it is detected that the electronic hydraulic brake system is in a vehicle power-off state.

[0111] S202: When the duration of the vehicle power-off state reaches a preset time, the brake pedal of the vehicle is not stepped on, the vehicle speed is zero, and the parking system of the vehicle is in the parking state, determine the self-check strategy of each component in the electronic hydraulic brake system.

[0112] S203: Detecting each component in the electronic hydraulic brake system according to the self-detection strategy to complete the power-off self-detection.

[0113] The vehicle power-off state of the electronic hydraulic brake system refers to receiving the KL15 OFF signal. KL15 represents the vehicle power main line, which is responsible for supplying power to most of the electrical equipment on the vehicle.

[0114] There are many ways to detect the components of the electronic hydraulic brake system. In one implementation, when the electronic hydraulic brake system is in the vehicle power-off state, start timing and determine the duration of the vehicle power-off state, compare the duration of the vehicle power-off state with the preset timing duration, and when the duration of the vehicle power-off state is equal to the preset timing duration and the vehicle's brake pedal is not stepped on, the vehicle speed is zero, and the vehicle's parking system is in the parking state, enter the power-off self-test process, that is, determine the self-test strategy of each component in the electronic hydraulic brake system, and detect each component in the electronic hydraulic brake system based on the self-test strategy. For example, the solenoid valve group in the electronic hydraulic brake system is turned on or off, and each hydraulic circuit and hydraulic chamber in the electronic hydraulic brake system are tested to ensure that the electronic hydraulic brake system is normal and effective.

[0115] In another implementation method of testing each component of the electronic hydraulic brake system, when the vehicle is powered off for a preset time duration, the vehicle's brake pedal is not stepped on, the vehicle's speed is zero, and the vehicle's parking system is in the parking state, a power-off self-check is performed. When it is detected that the brake pedal is stepped on, the current power-off self-check is exited. When it is detected again that the electronic hydraulic brake system is powered off for a preset time duration, the vehicle's brake pedal is not stepped on, the vehicle's speed is zero, and the vehicle's parking system is in the parking state, a second power-off self-check is performed.

[0116] When the power-off self-test is performed again, if it is detected that the brake pedal is stepped on, the power-off self-test process will not be performed again during the process from the current vehicle ignition to the current power-off.

[0117] In another example, when the vehicle's power-off state lasts for a preset time, the vehicle's brake pedal is not pressed, the vehicle's speed is zero, and the vehicle's parking system is in the parking state, a power-off self-check process is performed. If it is detected during the self-check process that the brake pedal is pressed, the power-off self-check process is exited, the vehicle's normal power assistance is restored, and the second power-off self-check is waited for.

[0118] It should be noted that the duration of the vehicle power-off state can be set to 2 minutes, 4 minutes, 6 minutes or 8 minutes, and the present invention does not impose any specific limitation on this.

[0119] When the power-off self-test is completed, the power-off self-test information of the electronic hydraulic brake system is stored in an EEPROM (Electrically Erasable Programmable read only memory) for monitoring the state of the electronic hydraulic brake system.

[0120] In addition to determining whether it is necessary to inspect each component in the electronic hydraulic braking system based on the status of the electronic hydraulic braking system, it is also possible to obtain the vehicle's single mileage and compare the single mileage with the preset mileage. When the single mileage is less than or equal to the preset mileage, the power-off self-inspection process will not be performed during the period from the current ignition to the current power-off.

[0121] It should be noted that the preset driving mileage can be set to 400m, 500m, 600m, etc., and the embodiment of the present invention does not impose any specific limitation on this.

[0122] In order to improve the user experience, the overall detection time of the power-off self-test of each component in the electronic hydraulic brake system is set to not exceed a preset time according to the self-test strategy of each component in the electronic hydraulic brake system. The preset time can be set to 10s, 15s, 20s, etc., and the embodiment of the present invention does not make specific restrictions on this.

[0123] When the power-off self-test is completed, regardless of whether there is a fault in the electronic hydraulic brake system, the residual pressure in the electronic hydraulic brake system needs to be released to ensure subsequent driving safety.

[0124] There are many ways to implement the self-test of each component in the electronic hydraulic brake system according to the self-test strategy to complete the power-off self-test. In one implementation, Figure 4 As shown, the following steps are included:

[0125] Still refer to Figure 1 The components in the electronic hydraulic brake system include electric cylinder, master cylinder and solenoid valve group.

[0126] S301: Control the electric cylinder to establish a first preset pressure.

[0127] S302: Based on the first preset pressure, the power-on state of the solenoid valve group is controlled to complete the power-off self-test.

[0128] The solenoid valve group includes a PSV valve, a CSV valve, an IV valve, an OV valve, a SSV valve and a TSV valve.

[0129] After the control electric cylinder establishes the first preset pressure, the control solenoid valve group is in the power-off state, and the PSV1 valve is powered on for pressure detection, the IV1 valve is powered off for pressure detection, the OV1 valve is powered on for pressure detection, the OV1 valve and the IV2 valve are powered off for pressure detection, the OV2 valve is powered on for pressure detection, the OV2 valve is powered off and the PSV2 valve is powered on for pressure detection, the IV3 valve is powered off for pressure detection, the OV3 valve is powered on for pressure detection, the OV3 valve and the IV4 valve are powered off for pressure detection, the OV4 valve is powered on for pressure detection, the OV4 valve, the TSV valve and the CSV valve are powered off for pressure detection, and the SSV valve is powered on for pressure detection, so that each device can be tested after the electric cylinder builds pressure once. By performing power-off self-test in the above sequence, the time of power-off self-test can be reduced, and the number of times the motor is started and the solenoid valve is switched on and off can be reduced.

[0130] Based on the first preset pressure, there are multiple ways to control the power-on state of the solenoid valve group and complete the power-off self-test. In one implementation, Figure 5 As shown, the following steps are included:

[0131] Still refer to Figure 1 , the solenoid valve group includes PSV1 valve and PSV2 valve.

[0132] S302-1: Switch the PSV1 valve and PSV2 valve to the power-off state.

[0133] S302-2: Detect the real-time pressure of the master cylinder and the real-time pressure of the electric cylinder.

[0134] S302-3: Based on the real-time pressure of the master cylinder, the first preset pressure and the real-time pressure of the electric cylinder, determine the working states of the electric cylinder, the PSV1 valve and the PSV2 valve.

[0135] Reference Figure 6 ,for Figure 1 Schematic diagram of the structure when the solenoid valve group is switched to the power-off state. In the figure, when the state of the solenoid valve group in the electronic hydraulic brake system is switched to the power-off state, since the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve are normally open valves, when the solenoid valve group in the electronic hydraulic brake system is in the power-off state, the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve in the electronic hydraulic brake system are in the power-off state, that is, the state of allowing flow to pass. Except for the above-mentioned CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve, the other solenoid valves are in the power-off state, that is, the state of not allowing flow to pass.

[0136] When the state of the solenoid valve group of the electronic hydraulic brake system is switched to the power-off state, the PSV1 valve and the PSV2 valve are also in the power-off state. If there is no abnormality in the PSV1 valve and the PSV2 valve, the PSV1 valve and the PSV2 valve can seal the pressure in the electric cylinder in the electric cylinder, and the hydraulic pressure in other oil circuits in the electronic hydraulic brake system is 0. When the PSV1 valve or the PSV2 valve is abnormal, the PSV1 valve and the PSV2 valve cannot seal the pressure in the electric cylinder in the electric cylinder, and the pressure will leak from the electric cylinder to other oil circuits in the electronic hydraulic brake system, making the hydraulic pressure in other oil circuits in the electronic hydraulic brake system not 0.

[0137] For example, when the PSV1 valve or the PSV2 valve leaks, since the CSV1 valve and the CSV2 valve are in a power-off state, the hydraulic pressure can leak to the master cylinder through the oil circuit between the PSV1 valve and the CSV1 valve or leak to the master cylinder through the oil circuit between the PSV2 valve and the CSV2 valve. Therefore, the presence of hydraulic pressure in the master cylinder can be detected at the master cylinder, that is, it is detected that the real-time pressure of the master cylinder is not 0.

[0138] In one example, when the real-time pressure of the master cylinder is zero and the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is considered that the electric cylinder has no leakage, and the PSV1 valve and the PSV2 valve can correctly seal the flow, that is, the PSV1 valve and the PSV2 valve have no forward leakage, and the motor of the electric cylinder is controlled normally, and the PSV1 valve and the PSV2 valve are controlled normally. When the real-time pressure of the master cylinder is not zero or the real-time pressure of the electric cylinder is inconsistent with the first preset pressure, the electric cylinder leaks, the PSV1 valve and the PSV2 valve have forward leakage, the PSV valve is abnormally controlled, or the motor is abnormally controlled.

[0139] In another example, when the real-time pressure of the master cylinder is zero, the first displacement of the piston corresponding to the real-time pressure of the electric cylinder is determined, the target displacement of the piston corresponding to the first preset pressure is determined, and the first displacement is compared with the target displacement. When the first displacement is equal to the target displacement, it is determined that the electric cylinder has no leakage, and the PSV1 valve and the PSV2 valve can correctly seal the flow, that is, the PSV1 valve and the PSV2 valve have no forward leakage, and the motor of the electric cylinder is controlled normally, and the PSV1 valve and the PSV2 valve are controlled normally. When the master cylinder pressure is not zero or the first displacement is inconsistent with the target displacement, it is determined that the electric cylinder leaks, the PSV1 valve and the PSV2 valve have forward leakage, the PSV valve is abnormally controlled, or the motor is abnormally controlled.

[0140] In another example, when the real-time pressure of the master cylinder is zero, the first displacement of the piston corresponding to the real-time pressure of the electric cylinder is determined, the target displacement corresponding to the first preset pressure is determined, and the absolute value of the difference between the first displacement and the target displacement is calculated. When the absolute value is less than or equal to the preset error, it is determined that the electric cylinder has no leakage, and the PSV1 valve and the PSV2 valve can correctly seal the flow, that is, the PSV1 valve and the PSV2 valve have no forward leakage, and the electric cylinder's motor is controlled normally, and the PSV1 valve and the PSV2 valve are controlled normally. When the first pressure of the master cylinder is not zero or the absolute value is greater than the preset error, it is determined that the electric cylinder is leaking, the PSV1 valve and the PSV2 valve have forward leakage, the PSV valve is abnormally controlled, or the motor is abnormally controlled.

[0141] Based on the first preset pressure, the power-on state of the solenoid valve group is controlled to complete the power-off self-test. In one implementation, Figure 7 As shown, the following steps are included:

[0142] Still refer to Figure 1 The solenoid valve group includes an IV1 valve, an IV2 valve, an IV3 valve, an IV4 valve, a CSV1 valve and a CSV2 valve. The CSV1 valve is connected to the IV1 valve and the IV2 valve respectively through an oil circuit, and the CSV2 valve is connected to the IV3 valve and the IV4 valve respectively through an oil circuit.

[0143] S302-4: Control the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve, PSV1 valve, and IV4 valve to be in an energized state.

[0144] S302-5: Detect the real-time pressure of the electric cylinder.

[0145] S302-6: Determine the working status of the CSV1 valve, the IV1 valve, and the IV2 valve based on the real-time pressure of the electric cylinder and the first preset pressure.

[0146] like Figure 8 As shown, the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve, IV4 valve and PSV1 valve in the electronic hydraulic brake system are energized, and all the solenoid valves in the electronic hydraulic control system except the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve, IV4 and PSV1 valve are in the de-energized state.

[0147] When the electric cylinder builds up the first preset pressure, when the PSV1 valve is in the energized state, the hydraulic pressure at the electric cylinder leaks to the oil circuit connecting the PSV1 valve and the CSV1 valve, and the oil circuit connecting the CSV1 valve and the IV1 valve and the IV2 valve. When the CSV1 valve leaks in the reverse direction, the hydraulic pressure will leak from the CSV1 valve to the master cylinder. When there is a leak in the IV1 valve or the IV2 valve, the first preset pressure built up by the electric cylinder will leak to the first wheel end or the second wheel end.

[0148] In one example, the working states of the CSV1 valve, the IV1 valve, and the IV2 valve may be determined based on a comparison result between the real-time pressure of the electric cylinder and the first preset pressure.

[0149] When the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is determined that the CSV1 valve has no reverse leakage, the IV1 valve and the IV2 valve have no forward leakage, and when the real-time pressure of the electric cylinder is consistent with the first preset pressure, it can also be determined that the PSV1 valve is controlled normally.

[0150] When the real-time pressure of the electric cylinder is inconsistent with the first preset pressure, it can be determined that the CSV1 valve has reverse leakage when the real-time pressure detected by the master cylinder is not 0. If pressure is detected at the first wheel end or the second wheel end, the IV1 valve or the IV2 valve has forward leakage.

[0151] The pressure sensor at the electric cylinder compares the real-time pressure of the electric cylinder with the first preset pressure. When the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is determined that the CSV1 valve has no reverse leakage, and it is determined that the IV1 valve and the IV2 valve have no forward leakage. When the real-time pressure of the electric cylinder is inconsistent with the first preset pressure, it is determined that the CSV1 valve is reversely leaking, the IV1 valve and the IV2 valve are forward leaking, or the PSV1 valve is abnormally controlled.

[0152] In another example, the target displacement of the piston corresponding to the first preset pressure can be determined, the first displacement corresponding to the real-time pressure of the electric cylinder can be determined, and the first displacement can be compared with the target displacement. When the first displacement is consistent with the target displacement, it is determined that the CSV1 valve has no reverse leakage, the IV1 valve and the IV2 valve have no forward leakage, and the PSV1 valve is controlled normally. When the first displacement is inconsistent with the target displacement and when the real-time pressure detected in the master cylinder is not 0, it is determined that the CSV1 valve has reverse leakage. If the first displacement is inconsistent with the target displacement and pressure is detected at the wheel end, there is forward leakage in the IV1 valve or the IV2 valve.

[0153] Based on the sequence of detecting the working status of the electric cylinder, PSV1 valve and PSV2 valve and detecting the working status of the CSV1 valve, IV1 valve and IV2 valve, the electric cylinder, PSV1 valve and PSV2 valve can be detected based on the detection step of the working status of the electric cylinder, PSV1 valve and PSV2 valve first, and then the specific step of detecting the working status of the CSV1 valve, IV1 valve and IV2 valve is detected on the basis of the detection of the electric cylinder, PSV1 valve and PSV2 valve. That is, when the first preset pressure is established for the electric cylinder and the electromagnetic valve group in the electronic hydraulic brake system is in the power-off state, the electric cylinder, PSV1 valve and PSV2 valve are detected, and when the electric cylinder maintains the first preset pressure and the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve, IV4 and PSV1 valve are in the power-on state, the working status of the CSV1 valve, IV1 valve and IV2 valve is detected.

[0154] The solenoid valve group also includes an OV1 valve, which controls the power-on state of the solenoid valve group based on the first preset pressure, and completes the power-off self-test, such as Fig. 9 As shown, the following steps are included:

[0155] S302-7: Control IV1 valve to the power-off state.

[0156] S302-8: Detect the real-time pressure of the electric cylinder.

[0157] S302-9: Based on the real-time pressure of the electric cylinder and the first preset pressure, determine the working states of the OV1 valve, the IV1 valve, the wheel end corresponding to the IV1 valve, and the wheel end pipeline corresponding to the IV1 valve.

[0158] like Fig.10 As shown, in Figure 8 On the basis of, the IV1 valve is in a power-off state. When the IV1 valve is controlled normally, the hydraulic pressure can pass through the IV1 valve to the oil circuit connected to the OV1 valve and push the hydraulic pressure to the first wheel end, that is, the hydraulic pressure can be detected at the first wheel end, and the hydraulic pressure detected at the first wheel end is consistent with the first preset pressure. When the OV1 valve has no leakage, the hydraulic pressure will not leak through the OV1 valve and the oil circuit connecting the OV1 valve and the oil tank module.

[0159] In one example, by detecting the comparison result between the real-time pressure of the electric cylinder and the first preset pressure, when the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is determined that the IV1 valve is controlled normally and the OV1 valve has no leakage. The wheel end corresponding to IV1 has no leakage and the wheel end pipeline corresponding to the IV1 valve has no leakage. When the real-time pressure of the electric cylinder is inconsistent with the first preset pressure, it is determined that the IV1 valve is abnormally controlled or the OV1 valve has no leakage or the wheel end corresponding to the IV1 valve has no leakage or the wheel end pipeline corresponding to the IV1 valve has no leakage.

[0160] In another example, the first displacement of the piston corresponding to the real-time pressure of the electric cylinder is determined, the target displacement of the piston corresponding to the first preset pressure is determined, and the first displacement is compared with the target displacement. When the first displacement is equal to the target displacement, it is determined that the IV1 valve is controlled normally and the OV1 valve has no leakage. The wheel end corresponding to the IV1 valve has no leakage and the wheel end pipeline corresponding to the IV1 valve has no leakage. When the first displacement is inconsistent with the target displacement, it is determined that the IV1 valve is abnormally controlled or the OV1 valve is leaking or the wheel end corresponding to the IV1 valve is leaking or the wheel end pipeline corresponding to the IV1 valve is leaking.

[0161] In another example, the first displacement of the piston corresponding to the real-time pressure of the electric cylinder is determined, the target displacement corresponding to the first preset pressure is determined, and the absolute value of the difference between the first displacement and the target displacement is calculated. When the absolute value is less than or equal to the preset error, it is determined that the IV1 valve is controlled normally and the OV1 valve has no leakage. There is no leakage at the wheel end corresponding to IV1 and there is no leakage at the wheel end pipeline corresponding to the IV1 valve. When the absolute value is greater than the preset error, it is determined that the IV1 valve is abnormally controlled or the OV1 valve is leaking or the wheel end corresponding to the IV1 valve is leaking or the wheel end pipeline corresponding to the IV1 valve is leaking.

[0162] S302-10: Control the OV1 valve to be energized.

[0163] S302-11: Detect the real-time pressure of the electric cylinder.

[0164] S302-12: Determine the working state of the OV1 valve based on the real-time pressure of the electric cylinder and the first preset pressure.

[0165] When the conduction state of the OV1 valve is detected, the electric cylinder establishes a first preset pressure and the pressure of the electric cylinder is maintained at the first preset pressure. Fig.11 As shown, in Fig.10 On the basis of, the OV1 valve is controlled to be powered on. Since the OV1 valve is powered on, the hydraulic pressure will be released to the small oil pot through the oil circuit of the OV1 valve and the oil pot module. At this time, in order to maintain the first preset pressure, the motor of the electric cylinder continues to work, and the piston corresponding to the electric cylinder continues to push forward to maintain the first preset pressure of the electric cylinder.

[0166] In one example, when the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is determined that the OV1 valve is controlled normally, that is, the OV1 valve is conducted normally.

[0167] In another example, the displacement of the piston corresponding to the electric cylinder can be determined to judge whether the conduction of the OV1 valve is normal. If it is detected that the displacement of the piston corresponding to the electric cylinder is consistent with the displacement corresponding to maintaining the first preset pressure, it is determined that the conduction of the OV1 valve is normal.

[0168] Based on the first preset pressure, the power-on state of the solenoid valve group is controlled, and the power-off self-test is completed, and the following steps are also included: Fig.12 As shown, the following steps are included:

[0169] S302-13: Control the OV1 valve and IV2 valve to the power-off state.

[0170] S302-14: Detect the real-time pressure of the electric cylinder.

[0171] S302-15: Based on the real-time pressure of the electric cylinder and the first preset pressure, determine the working status of the IV2 valve, the OV2 valve, the wheel end corresponding to the IV2 valve, and the wheel end pipeline corresponding to the IV2 valve.

[0172] like Fig.13 As shown, in Fig.11 On the basis of, the OV1 valve and IV2 valve are controlled to be in the de-energized state, so that the OV1 valve is in the de-energized state and the IV2 valve is in the open state. After the OV1 valve is de-energized, the hydraulic pressure will no longer be released to the oil tank module. When the IV2 valve is opened, the hydraulic pressure will be pushed to the second wheel end through the IV2 valve.

[0173] When the real-time pressure of the electric cylinder is consistent with the first preset pressure, it can be determined that the IV2 valve is conducting normally, the OV2 valve has no leakage, the wheel end corresponding to the IV2 valve has no leakage, and the wheel end pipeline corresponding to the IV2 valve has no leakage.

[0174] If there is leakage at the wheel end corresponding to the IV2 valve, i.e. the second wheel end, then Fig.13 The hydraulic pressure in the entire conductive oil circuit will change, that is, the real-time pressure of the electric cylinder is inconsistent with the first preset pressure. When the IV2 valve is abnormally controlled, the hydraulic pressure pushed to the second wheel end by the electric cylinder cannot be detected at the second wheel end. When the OV2 valve leaks, the hydraulic pressure will leak into the oil pot through the OV2 valve, causing the real-time pressure of the electric cylinder to be inconsistent with the first preset pressure. When the wheel-end pipeline corresponding to the IV2 valve leaks, the real-time pressure of the electric cylinder will also be inconsistent with the first preset pressure. Therefore, the working status of the IV2 valve, the OV2 valve, the wheel end corresponding to the IV2 valve, and the wheel-end pipeline corresponding to the IV2 valve can be determined by comparing the real-time pressure of the electric cylinder with the first preset pressure.

[0175] S302-16: Control the OV2 valve to be energized.

[0176] S302-17: Detect the real-time pressure of the electric cylinder.

[0177] S302-18: Determine the working state of the OV2 valve based on the real-time pressure of the electric cylinder and the first preset pressure.

[0178] like Fig.14 As shown, in Fig.13Based on the above, the OV2 valve is controlled to be in the energized state. The conduction state of the OV2 valve is determined by comparing the real-time pressure of the electric cylinder with the first preset pressure for the same reason as the OV1 valve is in the energized state, which will not be described in detail.

[0179] The solenoid valve group also includes IV3 valve and IV4 valve. The CSV2 valve is connected to the IV3 valve and IV4 valve through an oil circuit. Based on the first preset pressure, the power-on state of the solenoid valve group is controlled to complete the power-off self-test. Fig.15 As shown, the following steps are included:

[0180] S302-19: Control the CSV1 valve, CSV2 valve, IV3 valve, IV4 valve and PSV2 valve to be energized.

[0181] S302-20: Detect the real-time pressure of the electric cylinder.

[0182] S302-21: Based on the real-time pressure of the electric cylinder and the first preset pressure, determine the working status of the CSV2 valve, the IV3 valve and the IV4 valve.

[0183] like Fig.16 , CSV1 valve, CSV2 valve, IV3 valve, IV4 valve and PSV2 valve are controlled to be energized.

[0184] In one example, the hydraulic pressure of the electric cylinder is released through the PSV2 valve to the oil circuit connected to the PSV2 valve by IV3. When the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is determined that the CSV2 valve has no reverse leakage, and the IV3 valve and the IV4 valve have no leakage. When the real-time pressure of the electric cylinder is inconsistent with the first preset pressure, it is determined that the CSV2 valve has reverse leakage, the IV3 valve has leakage, or the IV4 valve has leakage.

[0185] In another example, the displacement of the piston corresponding to the electric cylinder can be determined to determine the working status of the CSV2 valve, the IV3 valve, and the IV4 valve. If it is detected that the first displacement of the piston corresponding to the electric cylinder is consistent with the target displacement corresponding to the first preset pressure, it is determined that the CSV2 valve has no reverse leakage, and the IV3 valve and the IV4 valve have no leakage. If it is detected that the first displacement of the piston corresponding to the electric cylinder is inconsistent with the target displacement corresponding to the first preset pressure, it is determined that the CSV2 valve has reverse leakage, the IV3 valve has leakage, or the IV4 valve has leakage.

[0186] When the CSV2 valve has reverse leakage, the hydraulic pressure will leak through the CSV2 valve to the master cylinder. When the pressure detector of the master cylinder detects that the pressure of the master cylinder is not zero, it is determined that the CSV2 valve has reverse leakage. When the IV3 valve leaks, the hydraulic pressure will leak through the IV3 valve to the third wheel end. When the pressure sensor based on the third wheel end detects that the pressure is not zero, it is determined that the IV3 valve is leaking.

[0187] Since the IV4 valve is connected to the IV3 valve through an oil circuit, when the IV4 valve leaks, the hydraulic pressure is released through the PSV2 valve to the oil circuit connecting the IV3 valve and the PSV2 valve and the oil circuit connecting the IV3 valve and the IV4 valve. Therefore, when the IV4 valve leaks, the hydraulic pressure will leak through the IV4 valve to the fourth wheel end, and the pressure will be detected by the pressure sensor corresponding to the fourth wheel end. When the pressure detected by the pressure sensor corresponding to the fourth wheel end is not zero, it is determined that the IV4 valve is leaking.

[0188] The solenoid valve group also includes an OV3 valve and an OV4 valve, the OV3 valve is connected to the IV3 valve, and the OV4 valve is connected to the IV4 valve. Based on the first preset pressure, the power-on state of the solenoid valve group is controlled, and the power-off self-test is completed, such as Fig.17 As shown, the following steps are included:

[0189] S302-22: Control IV3 valve to the power-off state.

[0190] S302-23: Detect the real-time pressure of the electric cylinder.

[0191] S302-24: Based on the real-time pressure of the electric cylinder and the first preset pressure, determine the working status of the IV3 valve, the OV3 valve, the wheel end corresponding to the IV3 valve, and the pipeline of the wheel end corresponding to the IV3 valve.

[0192] like Fig.18 As shown, in Fig.16 On the basis of, the IV3 valve is controlled to be in the power-off state.

[0193] When the IV3 valve is in the de-energized state, the hydraulic pressure leaks through the IV3 valve into the oil passage connecting IV3 and OV3.

[0194] In one example, the real-time pressure of the electric cylinder is compared with the first preset pressure, and the leakage of the IV3 valve, the OV3 valve, the wheel end corresponding to the IV3 valve, and the pipeline corresponding to the wheel end of the IV3 valve is determined based on the comparison result. When the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is determined that the IV3 valve is normally conducted, the OV3 valve is not leaking, the wheel end corresponding to the IV3 valve is not leaking, and the pipeline corresponding to the wheel end of the IV3 valve is not leaking. When the real-time pressure of the electric cylinder is inconsistent with the first preset pressure, it is determined that the IV3 valve is abnormally controlled, the OV3 valve is leaking, the wheel end corresponding to the IV3 valve is leaking, or the pipeline corresponding to the wheel end of the IV3 valve is leaking.

[0195] In another example, the first displacement of the piston corresponding to the real-time pressure of the electric cylinder is determined, the target displacement of the piston corresponding to the first preset pressure is determined, and the first displacement is compared with the target displacement. When the first displacement is equal to the target displacement, it is determined that the IV3 valve is normally connected, the OV3 valve has no leakage, the wheel end corresponding to the IV3 valve has no leakage, and the pipeline of the wheel end corresponding to the IV3 valve has no leakage. When the first displacement is inconsistent with the target displacement, it is determined that the IV3 valve is abnormally controlled, the OV3 valve corresponding to the IV3 valve is leaking, the wheel end corresponding to the IV3 valve is leaking, or the pipeline of the wheel end corresponding to the IV3 valve is leaking.

[0196] In another example, the first displacement of the piston corresponding to the real-time pressure of the electric cylinder is determined, the target displacement corresponding to the first preset pressure is determined, and the absolute value of the difference between the first displacement and the target displacement is calculated. When the absolute value is less than or equal to the preset error, it is determined that the IV3 valve is conducting normally, the OV3 valve has no leakage, the wheel end corresponding to the IV3 valve has no leakage, and the pipeline of the wheel end corresponding to the IV3 valve has no leakage. When the absolute value is greater than the preset error, the IV3 valve is abnormally controlled, the OV3 valve corresponding to the IV3 valve is leaking, the wheel end corresponding to the IV3 valve is leaking, or the pipeline of the wheel end corresponding to the IV3 valve is leaking.

[0197] S302-25: Control the OV3 valve to be energized.

[0198] S302-26: Detect the real-time pressure of the electric cylinder.

[0199] S302-27: Determine the working state of the OV3 valve based on the real-time pressure of the electric cylinder and the first preset pressure.

[0200] When the conduction state of the OV3 valve is detected, the electric cylinder establishes a first preset pressure and the pressure of the electric cylinder is maintained at the first preset pressure.

[0201] like Fig.19 As shown, in Fig.18 On this basis, the OV3 valve is controlled to be energized.

[0202] Since the OV3 valve is in the energized state, the hydraulic pressure will be released to the oil pot through the oil circuit of the OV3 valve and the oil pot module. At this time, in order to maintain the first preset pressure, the motor of the electric cylinder continues to work, and the piston corresponding to the electric cylinder continues to push forward to maintain the first preset pressure of the electric cylinder.

[0203] In one example, when the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is determined that the OV3 valve is controlled normally, that is, the OV3 valve is conducted normally.

[0204] In another example, the displacement of the piston corresponding to the electric cylinder can be determined to judge whether the conduction of the OV3 valve is normal. If it is detected that the displacement of the piston corresponding to the electric cylinder is consistent with the displacement corresponding to maintaining the first preset pressure, it is determined that the conduction of the OV3 valve is normal.

[0205] S302-28: Control the OV3 valve and IV4 valve to the power-off state.

[0206] S302-29: Detect the real-time pressure of the electric cylinder.

[0207] S302-30: Based on the real-time pressure of the electric cylinder and the first preset pressure, determine the working status of the IV4 valve, the OV4 valve, the wheel end corresponding to the IV4 valve, and the pipeline of the wheel end corresponding to the IV4 valve.

[0208] like Fig. 20 As shown, in Fig.19 On the basis of the above, the OV3 valve and IV4 valve are controlled to be de-energized. After the OV3 valve is de-energized, the hydraulic pressure will no longer be released to the oil tank module. When the IV4 valve is opened, the hydraulic pressure will be pushed to the fourth wheel end through the IV4 valve.

[0209] When the real-time pressure of the electric cylinder is consistent with the first preset pressure, it can be determined that the IV4 valve is conducting normally, the OV4 valve corresponding to the IV4 valve has no leakage, the wheel end corresponding to the IV4 valve has no leakage, and the wheel end pipe corresponding to the IV4 valve has no leakage.

[0210] If there is leakage at the wheel end corresponding to the IV4 valve, i.e. the fourth wheel end, then Fig. 20 The hydraulic pressure in the entire conductive oil circuit will change, that is, the real-time pressure of the electric cylinder is inconsistent with the first preset pressure. When the IV4 valve is abnormally controlled, the hydraulic pressure pushed to the wheel end by the electric cylinder cannot be detected at the fourth wheel end. When the OV4 valve leaks, the hydraulic pressure will leak into the oil pot through the OV4 valve, causing the real-time pressure of the electric cylinder to be inconsistent with the first preset pressure. When the wheel end pipeline corresponding to the IV4 valve leaks, the real-time pressure of the electric cylinder will also be inconsistent with the first preset pressure. Therefore, the comparison result of the real-time pressure of the electric cylinder with the first preset pressure can be used to determine whether the IV4 valve, the OV4 valve, the wheel end corresponding to the IV4 valve, or the wheel end pipeline corresponding to the IV4 valve is leaking.

[0211] S302-31: Control the OV4 valve to be energized.

[0212] S302-32: Detect the real-time pressure of the electric cylinder, and determine the working state of the OV4 valve based on the real-time pressure of the electric cylinder and the first preset pressure.

[0213] like Fig.21 As shown, in Fig. 20 Based on the above, the OV4 valve is controlled to be in the energized state. The conduction state of the OV4 valve is determined by comparing the real-time pressure of the electric cylinder with the first preset pressure for the same reason as the OV3 valve is in the open state, which will not be described in detail.

[0214] The solenoid valve group also includes a TSV valve and an SSV valve. The SSV valve is connected to the master cylinder. The TSV valve is connected to the master cylinder. Based on the first preset pressure, the power-on state of the solenoid valve group is controlled to complete the power-off self-test. Fig. 22 As shown, the following steps are included:

[0215] S302-33: Control the PSV1 valve and PSV2 valve to the energized state.

[0216] S302-34: Detect the real-time pressure of the electric cylinder.

[0217] S302-35: Based on the real-time pressure of the electric cylinder and the first preset pressure, the working status of the CSV1 valve, the CSV2 valve, the TSV valve and the SSV valve.

[0218] S302-36: Detect the real-time pressure of the master cylinder.

[0219] S302-37: Based on the real-time pressure of the master cylinder and the real-time pressure of the electric cylinder, determine the working states of the pressure sensor of the master cylinder and the pressure sensor of the electric cylinder.

[0220] like Fig.23 As shown in the figure, the PSV1 valve and the PSV2 valve are in the energized state, and the other solenoid valves are in the de-energized state.

[0221] When the electric cylinder builds up the first preset pressure, the hydraulic pressure is released to the CSV1 valve and the CSV2 valve through the PSV1 valve and the PSV2 valve. When the CSV1 valve and the CSV2 valve are in the power-off state, the hydraulic pressure is released to the master cylinder through the CSV1 valve and the CSV2 valve.

[0222] Since the TSV valve is connected to the master cylinder, when the TSV valve leaks, the hydraulic pressure in the master cylinder will leak from the TSV valve to the oil tank module, causing the real-time pressure at the electric cylinder to decrease. When the SSV valve leaks, the hydraulic pressure will leak to the simulation chamber connected to the SSV valve, causing the real-time pressure at the electric cylinder to decrease.

[0223] Therefore, the operating states of the CSV1 valve, the CSV2 valve, the TSV valve, and the SSV valve may be determined based on the comparison result between the real-time pressure of the electric cylinder and the first preset pressure.

[0224] When the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is determined that the TSV valve and the SSV valve have no leakage, and the CSV1 valve and the CSV2 valve are controlled normally. When the real-time pressure of the electric cylinder is inconsistent with the first preset pressure, it is determined that the TSV valve or the SSV valve is leaking or the CSV1 valve and the CSV2 valve are abnormally controlled.

[0225] When the CSV1 valve and the CSV2 valve are abnormally controlled, the pressure sensor at the master cylinder cannot detect the pressure. Therefore, to determine whether the CSV1 valve and the CSV2 valve are abnormally controlled, the pressure of the master cylinder can be detected. When it is detected that the real-time pressure of the master cylinder is consistent with the real-time pressure of the electric cylinder, it is determined that the CSV1 valve and the CSV2 valve are controlled normally and the pressure sensor of the master cylinder and the pressure sensor of the electric cylinder are normal.

[0226] S302-38: Control the SSV valve to be energized.

[0227] S302-39: Detect the real-time pressure of the electric cylinder, and determine the working state of the SSV valve based on the real-time pressure of the electric cylinder and the first preset pressure.

[0228] like Fig.24 As shown, in Fig.23 On the basis of, the SSV valve is controlled to be in an energized state.

[0229] In one example, when the SSV valve is in an energized state, hydraulic pressure is released from the SSV valve into the simulation chamber. When the real-time pressure of the electric cylinder is consistent with the first preset pressure, it is determined that the flow conduction of the SSV valve is normal.

[0230] In another example, when the SSV valve is in the energized state, hydraulic pressure will be released from the SSV valve into the simulation chamber, the electric cylinder establishes a first preset pressure and the pressure of the electric cylinder is maintained at the first preset pressure. In order to maintain the first preset pressure, the motor of the electric cylinder continues to work, and the piston corresponding to the electric cylinder continues to push forward to maintain the first preset pressure of the electric cylinder. When it is detected that the displacement of the piston corresponding to the electric cylinder is consistent with the displacement corresponding to maintaining the first preset pressure, it is determined that the SSV valve is conducting normally.

[0231] The power-off self-test solution of the present invention can also detect the conduction state of the TSV valve. Fig.23 On the basis of, the TSV valve is turned on, and when it is detected that the real-time pressure corresponding to the master cylinder is zero or the real-time pressure detected by the electric cylinder is zero, it is determined that the TSV valve is turned on normally.

[0232] Since one end of the TSV valve is connected to the master cylinder and the other end of the TSV valve is connected to the oil pot module, when the TSV is controlled normally and the TSV valve is energized, the hydraulic pressure will leak into the oil pot module, causing the pressure in the entire electronic hydraulic brake system to leak into the oil pot module, making the real-time pressure detection of the electric cylinder zero and the real-time pressure detection of the master cylinder zero.

[0233] An embodiment of the present invention further provides a vehicle, including a processor and a memory, wherein the memory stores a computer program that can be executed by the processor, and the processor can execute the computer program to implement the power-off self-test method.

[0234] In the embodiments provided by the present invention, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present invention. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, program segment or a part of the code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0235] In addition, each functional module in each embodiment of the present invention can be integrated together to form an independent part, or each module can exist separately, or two or more modules can be integrated to form an independent part. If the function is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program code.

[0236] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0237] The above are only various embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A power-off self-test method, applied to a vehicle controller, wherein the vehicle controller is communicatively connected to an electronic hydraulic brake system, characterized in that: The method comprises: The timing starts when it is detected that the electronic hydraulic brake system is in the vehicle power-off state; When the duration of the power-off state of the whole vehicle reaches a preset time, the brake pedal of the vehicle is not stepped on, the vehicle speed is zero, and the parking system of the vehicle is in the parking state, determining the self-check strategy of each component in the electronic hydraulic brake system; The components in the electronic hydraulic brake system are tested respectively according to the self-test strategy to complete the power-off self-test; the components in the electronic hydraulic brake system include an electric cylinder, a master cylinder and a solenoid valve group, the vehicle controller is in communication connection with the electric cylinder, the master cylinder and the solenoid valve group, and the steps of testing the components in the electronic hydraulic brake system respectively according to the self-test strategy to complete the power-off self-test include: Controlling the electric cylinder to establish a first preset pressure; Based on the first preset pressure, controlling the power-on state of the solenoid valve group to complete power-off self-test; The solenoid valve group includes a PSV1 valve and a PSV2 valve. The step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test includes: Switch the PSV1 valve and the PSV2 valve to a power-off state; Detecting the real-time pressure of the master cylinder and the real-time pressure of the electric cylinder; Based on the real-time pressure of the master cylinder, the first preset pressure and the real-time pressure of the electric cylinder, determining the working states of the electric cylinder, the PSV1 valve and the PSV2 valve to detect leakage of the PSV1 valve or the PSV2 valve; The solenoid valve group further includes an IV1 valve, an IV2 valve, an IV3 valve, an IV4 valve, a CSV1 valve and a CSV2 valve, wherein the CSV1 valve is respectively connected to the IV1 valve and the IV2 valve through an oil circuit, and the CSV2 valve is respectively connected to the IV3 valve and the IV4 valve through an oil circuit. Based on the first preset pressure, the power-on state of the solenoid valve group is controlled to complete the power-off self-test step, including: Controlling the CSV1 valve, CSV2 valve, IV1 valve, IV2 valve, IV3 valve and IV4 valve to be in an energized state; Control the PSV1 valve to be energized; Detecting the real-time pressure of the electric cylinder; Based on the real-time pressure of the electric cylinder and the first preset pressure, determining the working states of the CSV1 valve, the IV1 valve and the IV2 valve, so as to detect the leakage of the CSV1 valve, the IV1 valve and the IV2 valve, and detecting the controlled state of the PSV1 valve; The step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test includes: Controlling the CSV1 valve, CSV2 valve, IV3 valve, IV4 valve and PSV2 valve to be in an energized state; Detecting the real-time pressure of the electric cylinder; Based on the real-time pressure of the electric cylinder and the first preset pressure, the working states of the CSV2 valve, the IV3 valve and the IV4 valve are determined to detect leakage of the CSV2 valve, the IV3 valve and the IV4 valve.

2. The method according to claim 1, characterized in that The solenoid valve group further includes an OV1 valve, and the OV1 valve is connected to the IV1 valve. When the CSV1 valve, the CSV2 valve, the IV1 valve, the IV2 valve, the IV3 valve, the PSV1 valve, and the IV4 valve are controlled to be in an energized state, the step of controlling the energized state of the solenoid valve group based on the first preset pressure to complete the power-off self-test also includes: Controlling the IV1 valve to a power-off state; Detecting the real-time pressure of the electric cylinder; Determine the working states of the OV1 valve, the IV1 valve, the wheel end corresponding to the IV1 valve, and the wheel end pipeline corresponding to the IV1 valve based on the real-time pressure of the electric cylinder and the first preset pressure; Controlling the OV1 valve to be energized; Detecting the real-time pressure of the electric cylinder; The working state of the OV1 valve is determined based on the real-time pressure of the electric cylinder and the first preset pressure.

3. The method according to claim 2, characterized in that The solenoid valve group further includes an OV2 valve, the OV2 valve is connected to the IV2 valve, and the step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test also includes: Controlling the OV1 valve and the IV2 valve to be in a power-off state; Detecting the real-time pressure of the electric cylinder; Based on the real-time pressure of the electric cylinder and the first preset pressure, determining the working states of the IV2 valve, the OV2 valve, the wheel end corresponding to the IV2 valve, and the wheel end pipeline corresponding to the IV2 valve; Controlling the OV2 valve to be in an energized state; Detecting the real-time pressure of the electric cylinder; The working state of the OV2 valve is determined based on the real-time pressure of the electric cylinder and the first preset pressure.

4. The method according to claim 1, characterized in that: The solenoid valve group further includes an OV3 valve and an OV4 valve, the OV3 valve is connected to the IV3 valve, the OV4 valve is connected to the IV4 valve, and when the CSV1 valve, the CSV2 valve, the IV3 valve, the IV4 valve and the PSV2 valve are in an energized state, the step of controlling the energized state of the solenoid valve group based on the first preset pressure to complete the power-off self-test also includes: Controlling the IV3 valve to a power-off state; Detecting the real-time pressure of the electric cylinder; Determine the working states of the IV3 valve, the OV3 valve, the wheel end corresponding to the IV3 valve, and the pipeline of the wheel end corresponding to the IV3 valve based on the real-time pressure of the electric cylinder and the first preset pressure; Controlling the OV3 valve to be in an energized state; Detecting the real-time pressure of the electric cylinder; Determining the working state of the OV3 valve based on the real-time pressure of the electric cylinder and the first preset pressure; Controlling the OV3 valve and the IV4 valve to be in a power-off state; Detecting the real-time pressure of the electric cylinder; Determine the working states of the IV4 valve, the OV4 valve, the wheel end corresponding to the IV4 valve, and the pipeline of the wheel end corresponding to the IV4 valve based on the real-time pressure of the electric cylinder and the first preset pressure; Controlling the OV4 valve to be in an energized state; Detecting the real-time pressure of the electric cylinder; The working state of the OV4 valve is determined based on the real-time pressure of the electric cylinder and the first preset pressure.

5. The method according to claim 1, characterized in that The solenoid valve group further includes a TSV valve and an SSV valve, the SSV valve is connected to the master cylinder, the TSV valve is connected to the master cylinder, and the step of controlling the power-on state of the solenoid valve group based on the first preset pressure to complete the power-off self-test includes: Controlling the PSV1 valve and the PSV2 valve to be energized; Detecting the real-time pressure of the electric cylinder; Determining the working states of the CSV1 valve, the CSV2 valve, the TSV valve, and the SSV valve based on the real-time pressure of the electric cylinder and the first preset pressure; Detecting the real-time pressure of the master cylinder; Determining the working states of the pressure sensor of the master cylinder and the pressure sensor of the electric cylinder based on the real-time pressure of the master cylinder and the real-time pressure of the electric cylinder; Controlling the SSV valve to be in an energized state; Detecting the real-time pressure of the electric cylinder; The working state of the SSV valve is determined based on the real-time pressure of the electric cylinder and the first preset pressure.

6. A vehicle, characterized in that: The invention comprises a processor and a memory, wherein the memory stores a computer program executable by the processor, and the processor can execute the computer program to implement the power-off self-test method according to any one of claims 1 to 5.

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