Power-off self-checking method and vehicle

Abstract

An embodiment of the present invention provides a power-off self-test 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 timing time reaches a preset timing time, controlling the piston isolation valve and the circuit isolation valve in the electronic hydraulic brake system to an open state, controlling the electric cylinder to establish a first target hydraulic pressure, and when the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, closing the circuit isolation valve, controlling the electric cylinder to establish a second target hydraulic pressure, and performing a power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure to complete a two-way detection of the solenoid valve 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.

Description

Technical Field

[0001] The present invention relates to the technical 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] The solenoid valve is a key component of the entire braking system. The detection of the solenoid valve should include two-way detection. However, two-way detection requires different pressures in the electronic hydraulic brake system. How to control the solenoid valve is the difficulty of two-way detection. Summary of the invention

[0004] The object of the present invention is to provide a power-off self-inspection method and a vehicle, which can perform bidirectional detection on the solenoid valve of an electronic hydraulic brake system to perform power-off self-inspection to ensure driving safety.

[0005] In order to achieve the above purpose, the technical solution adopted by the embodiment of the present invention is as follows:

[0006] 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 controller is communicatively connected to an electronic hydraulic brake system, and the method comprises:

[0007] The timing starts when it is detected that the electronic hydraulic brake system is in a vehicle power-off state;

[0008] When the timing time reaches the preset timing time, the piston isolation valve and the circuit isolation valve in the electronic hydraulic brake system are controlled to be in an open state, wherein the circuit isolation valve is used to block the hydraulic pressure of the master cylinder, and the piston isolation valve is used to block the hydraulic pressure of the electric cylinder;

[0009] Controlling the electric cylinder to establish a first target hydraulic pressure;

[0010] When the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, closing the circuit isolation valve;

[0011] controlling the electric cylinder to establish a second target hydraulic pressure, wherein the first target hydraulic pressure is greater than the second target hydraulic pressure;

[0012] A power-off detection is performed on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure.

[0013] Optionally, the electronic hydraulic brake system includes a first pressure sensor and a second pressure sensor;

[0014] The first pressure sensor is used to detect the real-time hydraulic pressure corresponding to the master cylinder, and the second pressure sensor is used to detect the real-time hydraulic pressure corresponding to the electric cylinder;

[0015] The first pressure sensor is disposed between the master cylinder and the circuit isolation valve;

[0016] The second pressure sensor is disposed between the electric cylinder and the piston isolation valve.

[0017] Optionally, the piston isolation valve includes a PSV1 valve and a PSV2 valve, the circuit isolation valve includes a CSV1 valve and a CSV2 valve, the CSV1 valve is connected to the PSV1 valve via an oil circuit, and the CSV2 valve is connected to the PSV2 valve via an oil circuit, and the step of controlling the piston isolation valve and the circuit isolation valve in the electronic hydraulic brake system to be in an open state includes:

[0018] Controlling the CSV1 valve and the CSV2 valve to cut off power so that the CSV1 valve and the CSV2 valve are in an open state;

[0019] The PSV1 valve and the PSV2 valve are controlled to be energized so that the PSV1 valve and the PSV2 valve are in an open state.

[0020] Optionally, the electronic hydraulic brake system includes an SSV valve, the SSV valve is connected to the master cylinder, and the step of controlling the electric cylinder to establish the first target hydraulic pressure further includes:

[0021] The SSV valve is controlled to be energized so that the SSV valve is in an open state.

[0022] Optionally, the step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure includes:

[0023] Obtaining the real-time hydraulic pressure corresponding to the master cylinder;

[0024] comparing the real-time hydraulic pressure with the first target hydraulic pressure;

[0025] When the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, it is determined that the circuit isolation valve has no forward leakage.

[0026] Optionally, the circuit isolation valve includes a CSV1 valve and a CSV2 valve, and the step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure further includes:

[0027] Controlling the CSV2 valve to be powered off so that the CSV2 valve is in an open state;

[0028] Acquiring the real-time hydraulic pressure corresponding to the master cylinder and the real-time hydraulic pressure corresponding to the electric cylinder;

[0029] determining whether the real-time hydraulic pressure corresponding to the master cylinder is less than a first target hydraulic pressure;

[0030] When the real-time hydraulic pressure corresponding to the master cylinder is less than the first target hydraulic pressure, determining whether the real-time hydraulic pressure corresponding to the electric cylinder is greater than the second target hydraulic pressure;

[0031] When the real-time hydraulic pressure corresponding to the electric cylinder is greater than the second target hydraulic pressure, determining whether the real-time hydraulic pressure corresponding to the master cylinder is consistent with the real-time hydraulic pressure corresponding to the electric cylinder;

[0032] When the real-time hydraulic pressure corresponding to the master cylinder is consistent with the real-time hydraulic pressure corresponding to the electric cylinder, it is determined that the CSV2 valve is conducting normally.

[0033] Optionally, the electronic hydraulic brake system further includes a TSV valve and an oil pot, 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, and the step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure further includes:

[0034] Applying power to the CSV2 valve to close the CSV2 valve;

[0035] Applying electricity to the TSV valve to open the TSV valve;

[0036] Acquiring the real-time hydraulic pressure of the master cylinder;

[0037] When the real-time hydraulic pressure of the master cylinder is zero, it is determined that the TSV valve conduction is normal.

[0038] Optionally, the electronic hydraulic brake system further includes an SSV valve, the SSV valve is connected to the master cylinder through an oil circuit connected to the master cylinder by the CSV1 valve, and the step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure includes:

[0039] Controlling the SSV valve to cut off power so that the SSV valve is in a closed state;

[0040] De-energizing the CSV1 valve to open the CSV1 valve;

[0041] Acquiring the real-time hydraulic pressure of the electric cylinder and the real-time hydraulic pressure of the master cylinder;

[0042] When the real-time hydraulic pressure of the electric cylinder and the real-time hydraulic pressure of the master cylinder are both zero, it is determined that the CSV1 valve is conducting normally.

[0043] Optionally, the piston isolation valve includes a PSV1 valve and a PSV2 valve, and the step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure includes:

[0044] Controlling the CSV2 valve to be powered off so that the CSV2 valve is in an open state;

[0045] Power is cut off to the PSV1 valve and the PSV2 valve to make the PSV1 valve and the PSV2 valve in a closed state, so as to complete the power-off self-test.

[0046] In a second aspect, an embodiment of the present invention provides a vehicle, comprising a controller, a memory and an electronic hydraulic brake system, wherein the memory stores a computer program executable by the controller, and the controller can execute the computer program to implement the power-off self-test method to perform a power-off self-test on the electronic hydraulic brake system.

[0047] The present invention has the following beneficial effects:

[0048] The present invention starts timing when it is detected that the electronic hydraulic brake system is in a vehicle power-off state. When the timing time reaches a preset timing time, the piston isolation valve and the circuit isolation valve in the electronic hydraulic brake system are controlled to be in an open state, wherein the circuit isolation valve is used to block the hydraulic pressure of the master cylinder, and the piston isolation valve is used to block the hydraulic pressure of the electric cylinder, and the electric cylinder is controlled to establish a first target hydraulic pressure. When the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, the circuit isolation valve is closed, and the electric cylinder is controlled to establish a second target hydraulic pressure, wherein the first target hydraulic pressure is greater than the second target hydraulic pressure. Based on the first target hydraulic pressure and the second target hydraulic pressure, the electronic hydraulic brake system is subjected to a power-off detection to complete the bidirectional detection of the solenoid valve in the electronic hydraulic brake system, thereby ensuring that the electronic hydraulic brake system can work normally when it is started next time, and ensuring driving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] 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.

[0050] Figure 1 A schematic diagram of an electronic hydraulic brake system provided by an embodiment of the present invention;

[0051] Figure 2 A block diagram of a controller provided by an embodiment of the present invention;

[0052] Figure 3 One of the flowcharts of a power-off self-test method provided by an embodiment of the present invention;

[0053] Figure 4 One of the state switching schematic diagrams of the electronic hydraulic brake system provided by an embodiment of the present invention;

[0054] Figure 5 A second schematic diagram of state switching of an electronic hydraulic brake system provided by an embodiment of the present invention;

[0055] Figure 6 A second flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0056] Figure 7 A third flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0057] Figure 8 A third state switching diagram of the electronic hydraulic brake system provided by an embodiment of the present invention;

[0058] Fig. 9 A fourth flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0059] Fig.10 A fourth state switching diagram of the electronic hydraulic brake system provided in an embodiment of the present invention;

[0060] Fig.11 A fifth flowchart of a power-off self-test method provided by an embodiment of the present invention;

[0061] Fig.12 A fifth state switching diagram of the electronic hydraulic brake system provided in an embodiment of the present invention;

[0062] Fig.13 A structural block diagram of a power-off self-test device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] like Figure 1 As 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 piston isolation valve. The piston isolation valve includes a PSV1 valve and a PSV2 valve. The pressure buildup of the electric cylinder 31 is achieved by driving the piston movement in the electric cylinder by a 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 can be connected to the first wheel end and the second wheel end, the PSV2 valve can be connected to the third wheel end and the fourth wheel end, the PSV1 valve can also be connected to the first wheel end and the third wheel end, and the PSV2 valve is connected to the second wheel end and the fourth wheel end.

[0071] Figure 1 It is shown that the PSV1 valve of the main brake circuit 30 is connected to the IV1 valve and the IV2 valve through the oil circuit, and the PSV2 valve of the main brake circuit 30 is connected to the IV3 valve and the IV4 valve through the 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 open state, the electric cylinder 31 provides hydraulic pressure to the IV1 valve, the IV2 valve, the IV3 valve and the IV4 valve.

[0072] The mechanical brake circuit 40 includes a master cylinder 41 and a circuit isolation valve, the circuit isolation valve includes a CSV1 valve and a CSV2 valve, and the electronic hydraulic brake system also includes 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 first wheel end component 21 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 an open 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 closed 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, and the master cylinder 41 is connected to the brake pedal 43, and the master cylinder 41 is pressurized by stepping on the brake pedal 43.

[0073] 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 in a closed state, that is, a state in which flow is not allowed to pass, 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 in an open state, that is, a state in which flow is allowed to pass. 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.

[0074] In view of the discovery of the above problems, the present embodiment provides a power-off self-test method and a vehicle, which can start timing when it is detected that the electronic hydraulic brake system is in a vehicle power-off state. When the timing time reaches a preset timing time, the piston isolation valve and the circuit isolation valve in the electronic hydraulic brake system are controlled to be in an open state, and the electric cylinder is controlled to establish a first target hydraulic pressure. When the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, the circuit isolation valve is closed, and the electric cylinder is controlled to establish a second target hydraulic pressure. Based on the first target hydraulic pressure and the second target hydraulic pressure, the electronic hydraulic brake system is tested for power-off to complete the two-way detection of the solenoid valve in the electronic hydraulic brake system, thereby ensuring that the electronic hydraulic brake system can work normally when it is started next time, and ensuring driving safety. The solution provided in the present embodiment is elaborated in detail below.

[0075] This embodiment provides a vehicle controller that can perform power-off detection 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.

[0076] 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.

[0077] The vehicle controller 100 includes a power-off self-test device 110 , a memory 120 , and a controller 130 .

[0078] The components of the memory 120 and the controller 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 controller 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.

[0079] 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 controller 130 executes the program after receiving an execution instruction.

[0080] Please refer to Figure 3 , Figure 3 For application Figure 2 A flowchart of a power-off self-test of a vehicle controller 100 is provided, and the method including each step is described in detail below.

[0081] S201: Start timing when it is detected that the electronic hydraulic brake system is in a vehicle power-off state.

[0082] S202: When the timing time reaches a preset timing time, the piston isolation valve and the circuit isolation valve in the electronic hydraulic brake system are controlled to be in an open state.

[0083] The circuit isolation valve is used to block the hydraulic pressure of the master cylinder, and the piston isolation valve is used to block the hydraulic pressure of the electric cylinder.

[0084] S203: Control the electric cylinder to establish a first target hydraulic pressure.

[0085] S204: When the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, the circuit isolation valve is closed.

[0086] S205: Control the electric cylinder to establish a second target hydraulic pressure.

[0087] The first target hydraulic pressure is greater than the second target hydraulic pressure.

[0088] S206: Performing a power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure.

[0089] 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.

[0090] 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 when the timing time reaches the preset timing time 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. 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.

[0091] It should be noted that the preset timing time can be set to 5 minutes, 6 minutes, 7 minutes, etc., and the embodiment of the present invention does not impose any specific limitation on this.

[0092] In another implementation method of testing each component of the electronic hydraulic brake system, when the timing time of the whole vehicle power-off state reaches a preset timing time, 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, if it is detected that the brake pedal is stepped on, the current power-off self-test is exited, and when it is detected again that the timing time of the electronic hydraulic brake system in the whole vehicle power-off state reaches the preset timing time, 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-test is performed.

[0093] During the second power-off self-test, if it is detected that the brake pedal is stepped on, the power-off self-test process will no longer be performed during the process from the current vehicle ignition to the current power-off.

[0094] In another example, when the timing time of the vehicle's power-off state reaches a preset timing time, 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, the power-off self-check process is performed. If it is detected during the self-check process that the brake pedal is stepped on, 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] When the vehicle power-off time reaches the preset time, it will enter the power-off self-test process normally. Figure 4 As shown, the piston isolation valve in the electronic hydraulic brake system is controlled to be in an open state, that is, the PSV1 valve and the PSV2 valve are controlled to be in an open state, and the TSV valve is in a power-off state, so that the TSV valve is in a closed state. The circuit isolation valve in the electronic hydraulic brake system is controlled to be in an open state, that is, the CSV1 valve and the CSV2 valve are controlled to be in an open state.

[0101] When the vehicle power-off time reaches the preset time, it will enter the power-off self-test process normally. Figure 4 The IV1 valve, IV2 valve, IV3 valve and IV4 valve are controlled to be in a closed state, that is, the IV1 valve, IV2 valve, IV3 valve and IV4 valve are energized to make the IV1 valve, IV2 valve, IV3 valve and IV4 valve in a closed state to avoid hydraulic leakage when the electric cylinder builds pressure.

[0102] When the electric cylinder establishes the first target hydraulic pressure, the SSV valve is energized to open the SSV valve. When the PSV1 valve, the PSV2 valve, the CSV1 valve, and the CSV2 valve are all in the open state, the first target hydraulic pressure is pushed to the master cylinder through the PSV1 valve, the PSV2 valve, the CSV1 valve, and the CSV2 valve. Since the PSV1 valve is connected to the CSV1 valve, and the PSV2 valve is connected to the CSV2 valve, when the PSV1 valve and the CSV1 valve are in the open state, the hydraulic pressure can be pushed into the master cylinder through the PSV1 valve and the CSV1 valve, and when the PSV2 valve and the CSV2 valve are in the open state, the hydraulic pressure can be pushed into the master cylinder through the PSV2 valve and the CSV2 valve.

[0103] Still refer to Figure 4 The electronic hydraulic brake system includes a first pressure sensor 1 and a second pressure sensor 2. The first pressure sensor 1 is used to detect the real-time hydraulic pressure corresponding to the master cylinder 41, and the second pressure sensor 2 is used to detect the real-time hydraulic pressure corresponding to the electric cylinder 31. The first pressure sensor 1 is arranged between the master cylinder 41 and the circuit isolation valve, and the second pressure sensor 2 is arranged between the electric cylinder 31 and the piston isolation valve.

[0104] When the real-time hydraulic pressure of the master cylinder 41 detected by the first pressure sensor 1 is consistent with the first target hydraulic pressure, the first target hydraulic pressure is determined to be pushed to the master cylinder. When the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, the circuit isolation valve is closed. Figure 5 As shown, in Figure 4On the basis of, the CSV1 valve and the CSV2 valve are controlled to be in a closed state, and at this time, the first target hydraulic pressure is blocked in the master cylinder.

[0105] After the first target hydraulic pressure is sealed in the master cylinder, the motor corresponding to the electric cylinder is controlled to operate to establish the second target hydraulic pressure. When the CSV1 valve and the CSV2 valve are in the closed state, the second target hydraulic pressure will be sealed in the oil circuit in the conductive state.

[0106] Based on the first target hydraulic pressure and the second target hydraulic pressure, each solenoid valve in the electronic hydraulic brake system is closed and opened, so that power-off detection is performed based on changes in the first target hydraulic pressure and the second target hydraulic pressure.

[0107] Since the first target hydraulic pressure is greater than the second target hydraulic pressure, when the first target hydraulic pressure is blocked in the master cylinder, if there is no forward leakage in the circuit isolation valve, the pressure will not leak through the circuit isolation valve to the circuit connected to the piston isolation valve. When there is forward leakage in the circuit isolation valve, the real-time hydraulic pressure in the master cylinder will not meet the first target hydraulic pressure. When it is detected that the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, the circuit isolation valve is closed and the electric cylinder is controlled to establish the second target hydraulic pressure. When it is detected that the real-time hydraulic pressure of the electric cylinder is less than the second target hydraulic pressure, it indicates that the circuit isolation valve is leaking in the reverse direction. When it is detected that the real-time hydraulic pressure of the electric cylinder is consistent with the second target hydraulic pressure, it indicates that there is no reverse leakage in the circuit isolation valve.

[0108] Through the above scheme, bidirectional detection of the solenoid valve can be completed.

[0109] There are multiple ways to implement power-off detection of the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure. In one implementation, Figure 6 As shown, the following steps are included:

[0110] S206-1: Obtain the real-time hydraulic pressure corresponding to the master cylinder.

[0111] S206 - 2 : Compare the real-time hydraulic pressure with the first target hydraulic pressure.

[0112] S206-3: When the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, it is determined that there is no forward leakage of the circuit isolation valve.

[0113] In one example, the first pressure sensor detects the real-time hydraulic pressure of the master cylinder. When the reading of the first pressure sensor is consistent with the first target hydraulic pressure, it is determined that the circuit isolation valve has no positive leakage, that is, the CSV1 valve and the CSV2 valve have no positive leakage. When the CSV1 valve and the CSV2 valve leak, the hydraulic pressure of the master cylinder cannot be blocked in the master cylinder and will leak to other places in the electronic hydraulic brake system. At this time, the real-time hydraulic pressure of the master cylinder cannot reach the first target hydraulic pressure.

[0114] In another example, the electronic hydraulic brake system may further include a first displacement sensor connected to the master cylinder, and the first displacement sensor is used to detect the displacement of the piston in the master cylinder. Based on the real-time displacement of the piston in the master cylinder detected by the first displacement sensor, a target displacement corresponding to the first target hydraulic pressure is determined, and the real-time displacement is compared with the target displacement. When the real-time displacement is consistent with the target displacement, it is determined that the CSV1 valve and the CSV2 valve have no positive leakage.

[0115] In another example, based on the real-time displacement of the piston in the master cylinder detected by the first displacement sensor, the target displacement corresponding to the first target hydraulic pressure is determined, the absolute value of the difference between the real-time displacement and the target displacement is calculated, and the absolute value is compared with a preset error. When the absolute value is less than or equal to the preset error, it is determined that there is no forward leakage in the CSV1 valve and the CSV2 valve.

[0116] In another implementation of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure, as Figure 7 As shown, the following steps are included:

[0117] S206-4: Control the CSV2 valve to cut off the power so that the CSV2 valve is in the open state.

[0118] like Figure 8 As shown, in Figure 5 On the basis of the above, the CSV2 valve is controlled to be in the open state. When the CSV2 valve is in the open state, the hydraulic pressure in the master cylinder will be released through the CSV2 valve, and when the PSV1 valve and the PSV2 valve are also in the open state, the first target hydraulic pressure in the master cylinder and the second target hydraulic pressure in the electric cylinder will be hydraulically merged.

[0119] S206-5: Obtain the real-time hydraulic pressure corresponding to the master cylinder and the real-time hydraulic pressure corresponding to the electric cylinder.

[0120] The real-time hydraulic pressure of the master cylinder is detected based on the first pressure sensor corresponding to the master cylinder, and the real-time hydraulic pressure of the electric cylinder is detected based on the second pressure sensor corresponding to the electric cylinder.

[0121] S206-6: Determine whether the real-time hydraulic pressure corresponding to the master cylinder is less than the first target hydraulic pressure.

[0122] S206-7: When the real-time hydraulic pressure corresponding to the master cylinder is less than the first target hydraulic pressure, determine whether the real-time hydraulic pressure corresponding to the electric cylinder is greater than the second target hydraulic pressure.

[0123] S206-8: When the real-time hydraulic pressure corresponding to the electric cylinder is greater than the second target hydraulic pressure, determine whether the real-time hydraulic pressure corresponding to the master cylinder is consistent with the real-time hydraulic pressure corresponding to the electric cylinder.

[0124] S206-9: When the real-time hydraulic pressure corresponding to the master cylinder is consistent with the real-time hydraulic pressure corresponding to the electric cylinder, it is determined that the CSV2 valve is conducting normally.

[0125] Since the first target hydraulic pressure established by the electric cylinder is greater than the second target hydraulic pressure established, when the CSV2 valve is opened, the first target hydraulic pressure and the second target hydraulic pressure will be merged, and the merged pressure is less than the first target hydraulic pressure and greater than the second target hydraulic pressure. If the CSV2 valve is controlled normally, that is, the CSV2 valve is normally connected, the real-time hydraulic pressure of the master cylinder must be less than the first target hydraulic pressure before the CSV2 valve is opened, and the real-time hydraulic pressure of the electric cylinder must be greater than the second target hydraulic pressure before the CSV2 valve is opened. And, finally, the first target hydraulic pressure and the second target hydraulic pressure are merged into a fixed value. At this time Figure 8 The hydraulic pressure at each point in the oil circuit that is connected should be equal.

[0126] Therefore, the conduction state of the CSV2 valve can be detected based on the relationship between the real-time hydraulic pressure of the master cylinder and the first target hydraulic pressure, the relationship between the real-time hydraulic pressure of the electric cylinder and the second target hydraulic pressure, and the relationship between the real-time hydraulic pressure corresponding to the master cylinder and the real-time hydraulic pressure corresponding to the electric cylinder.

[0127] That is, when the real-time hydraulic pressure of the master cylinder is less than the first target hydraulic pressure, the real-time hydraulic pressure of the electric cylinder is greater than the second target hydraulic pressure, and the real-time hydraulic pressure of the master cylinder is consistent with the real-time hydraulic pressure of the electric cylinder, it is determined that the CSV2 valve is normally conductive.

[0128] In another implementation of power-off detection of the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure, as Fig. 9 As shown, the following steps are included:

[0129] S206-10: Power is supplied to the CSV2 valve to close the CSV2 valve, and power is supplied to the TSV valve to open the TSV valve.

[0130] like Fig.10 As shown, in Figure 8 On the basis of, the CSV2 valve is controlled to be closed, and the TSV valve is controlled to be open. The TSV valve is connected to the oil pot module, the oil pot module includes a small oil pot and a large oil pot, one end of the TSV valve is connected to the master cylinder, and the other end of the TSV valve is connected to the small oil pot.

[0131] When the CSV2 valve and CSV1 valve are in the closed state and the TSV valve is in the open state, the hydraulic pressure in the master cylinder will leak into the small oil pot.

[0132] S206-11: Obtain the real-time hydraulic pressure of the master cylinder.

[0133] S206-12: When the real-time hydraulic pressure of the master cylinder is zero, determine that the TSV valve conduction is normal.

[0134] When the real-time hydraulic pressure of the master cylinder is zero, it means that the hydraulic pressure in the master cylinder is released into the small oil pot through the TSV valve. At this time, the TSV valve conduction is normal. When the TSV valve conduction is abnormal, the real-time hydraulic pressure of the master cylinder is not zero.

[0135] In another implementation of power-off detection of the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure, as Fig.11 As shown, the following steps are included:

[0136] S206-13: Control the SSV valve to cut off the power so that the SSV valve is in a closed state, and cut off the power to the CSV1 valve so that the CSV1 valve is in an open state.

[0137] S206-14: Obtain the real-time hydraulic pressure of the electric cylinder and the real-time hydraulic pressure of the master cylinder.

[0138] S206-15: When the real-time hydraulic pressure of the electric cylinder and the real-time hydraulic pressure of the master cylinder are both zero, it is determined that the CSV1 valve is conducting normally.

[0139] like Fig.12 As shown, in Fig.10 On the basis of, the SSV valve is controlled to be closed, and the CSV1 valve is controlled to be open. At this time, the TSV valve is turned on, and the TSV valve is connected to the small oil pot through the master cylinder. When the TSV valve is turned on, the hydraulic pressure passing through the TSV valve will be released into the small oil pot to complete the pressure relief. When the CSV1 valve is in the open state, the PSV1 valve corresponding to the electric cylinder is connected to the CSV1 valve, and the hydraulic pressure in the electric cylinder will be released into the small oil pot through the PSV1 valve, CSV1 valve and TSV valve, so that the real-time hydraulic pressure at the electric cylinder is zero, and the hydraulic pressure in the master cylinder is also released into the small oil pot through the TSV valve, so that the real-time hydraulic pressure at the master cylinder is zero.

[0140] When the real-time hydraulic pressure of the electric cylinder and the real-time hydraulic pressure of the master cylinder are both zero, it is determined that the CSV1 valve is conducting normally.

[0141] Control the CSV2 valve to cut off the power so that the CSV2 valve is in the open state; cut off the power to the PSV1 valve and the PSV2 valve so that the PSV1 valve and the PSV2 valve are in the closed state to complete the power-off self-test.

[0142] Please refer to Fig.13 The embodiment of the present invention further provides a power-off self-test device, the power-off self-test device comprising:

[0143] The timing module 111 is used to start timing when it is detected that the electronic hydraulic brake system is in a vehicle power-off state;

[0144] The control module 112 is used to control the piston isolation valve and the circuit isolation valve in the electronic hydraulic brake system to be in an open state when the timing time reaches a preset timing time, wherein the circuit isolation valve is used to block the hydraulic pressure of the master cylinder, and the piston isolation valve is used to block the hydraulic pressure of the electric cylinder, and control the electric cylinder to establish a first target hydraulic pressure; when the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, close the circuit isolation valve; and control the electric cylinder to establish a second target hydraulic pressure, wherein the first target hydraulic pressure is greater than the second target hydraulic pressure;

[0145] The power-off self-detection module 113 is configured to perform a power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure.

[0146] 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.

[0147] 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.

[0148] 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.

[0149] 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 a vehicle power-off state; When the timing time reaches the preset timing time, the piston isolation valve and the circuit isolation valve in the electronic hydraulic brake system are controlled to be in an open state, wherein the circuit isolation valve is used to block the hydraulic pressure of the master cylinder, and the piston isolation valve is used to block the hydraulic pressure of the electric cylinder; Controlling the electric cylinder to establish a first target hydraulic pressure; When the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, closing the circuit isolation valve; controlling the electric cylinder to establish a second target hydraulic pressure, wherein the first target hydraulic pressure is greater than the second target hydraulic pressure; performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure; The piston isolation valve includes a PSV1 valve and a PSV2 valve, the circuit isolation valve includes a CSV1 valve and a CSV2 valve, the CSV1 valve is connected to the PSV1 valve via an oil circuit, and the CSV2 valve is connected to the PSV2 valve via an oil circuit. The step of controlling the piston isolation valve and the circuit isolation valve in the electronic hydraulic brake system to be in an open state includes: Controlling the CSV1 valve and the CSV2 valve to cut off power so that the CSV1 valve and the CSV2 valve are in an open state; Controlling the PSV1 valve and the PSV2 valve to be energized so that the PSV1 valve and the PSV2 valve are in an open state; The step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure includes: Obtaining the real-time hydraulic pressure corresponding to the master cylinder; comparing the real-time hydraulic pressure with the first target hydraulic pressure; When the real-time hydraulic pressure of the master cylinder is consistent with the first target hydraulic pressure, it is determined that the circuit isolation valve has no forward leakage; The step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure further includes: Controlling the CSV2 valve to be powered off so that the CSV2 valve is in an open state; Acquiring the real-time hydraulic pressure corresponding to the master cylinder and the real-time hydraulic pressure corresponding to the electric cylinder; determining whether the real-time hydraulic pressure corresponding to the master cylinder is less than a first target hydraulic pressure; When the real-time hydraulic pressure corresponding to the master cylinder is less than the first target hydraulic pressure, determining whether the real-time hydraulic pressure corresponding to the electric cylinder is greater than the second target hydraulic pressure; When the real-time hydraulic pressure corresponding to the electric cylinder is greater than the second target hydraulic pressure, determining whether the real-time hydraulic pressure corresponding to the master cylinder is consistent with the real-time hydraulic pressure corresponding to the electric cylinder; When the real-time hydraulic pressure corresponding to the master cylinder is consistent with the real-time hydraulic pressure corresponding to the electric cylinder, it is determined that the CSV2 valve is normally open; The electronic hydraulic brake system further includes a TSV valve and an oil pot, 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. The step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure also includes: Applying power to the CSV2 valve to close the CSV2 valve; Applying electricity to the TSV valve to open the TSV valve; Acquiring the real-time hydraulic pressure of the master cylinder; When the real-time hydraulic pressure of the master cylinder is zero, it is determined that the TSV valve conduction is normal.

2. The method according to claim 1, characterized in that The electronic hydraulic brake system includes a first pressure sensor and a second pressure sensor; The first pressure sensor is used to detect the real-time hydraulic pressure corresponding to the master cylinder, and the second pressure sensor is used to detect the real-time hydraulic pressure corresponding to the electric cylinder; The first pressure sensor is disposed between the master cylinder and the circuit isolation valve; The second pressure sensor is disposed between the electric cylinder and the piston isolation valve.

3. The method according to claim 1, characterized in that The electronic hydraulic brake system includes an SSV valve, the SSV valve is connected to the master cylinder, and the step of controlling the electric cylinder to establish the first target hydraulic pressure further includes: The SSV valve is controlled to be energized so that the SSV valve is in an open state.

4. The method according to claim 1, characterized in that: The electronic hydraulic brake system further includes an SSV valve, and the SSV valve is connected to the master cylinder through an oil circuit connected to the master cylinder by the CSV1 valve. The step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure includes: Controlling the SSV valve to cut off power so that the SSV valve is in a closed state; De-energizing the CSV1 valve to keep the CSV1 valve in an open state; Acquiring the real-time hydraulic pressure of the electric cylinder and the real-time hydraulic pressure of the master cylinder; When the real-time hydraulic pressure of the electric cylinder and the real-time hydraulic pressure of the master cylinder are both zero, it is determined that the CSV1 valve is conducting normally.

5. The method according to claim 4, characterized in that The step of performing power-off detection on the electronic hydraulic brake system based on the first target hydraulic pressure and the second target hydraulic pressure includes: Controlling the CSV2 valve to be powered off so that the CSV2 valve is in an open state; The PSV1 valve and the PSV2 valve are powered off to make them in a closed state, so as to complete the power-off self-test.

6. A vehicle, characterized in that: It includes a controller, a memory and an electronic hydraulic brake system, the memory stores a computer program that can be executed by the controller, and the controller can execute the computer program to implement the power-off self-test method as described in any one of claims 1 to 5 to perform a power-off self-test on the electronic hydraulic brake system.

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