A method for monitoring leakage of a brake system

Abstract

The present invention discloses a brake system leakage monitoring method, which utilizes the EBbooster controller in the EBbooster electronic booster to monitor the brake fluid pressure and wheel speed at different positions in the brake system, and uses the set judgment rules and processes to identify whether the brake system has a leakage risk, and find the specific brake fluid leakage position when the brake system has a leakage risk. The method makes full use of the inherent sensors and computing equipment of the brake system and the vehicle machine, and realizes the timely and accurate identification of the brake fluid leakage position in the brake system at a low cost.

Description

Technical Field

[0001] The invention relates to the technical field of brake system monitoring, and in particular to a brake system leakage monitoring method. Background Art

[0002] This patent is mainly aimed at vehicles with electric drive systems, including hybrid and pure electric vehicles; it involves a method for active monitoring and alarm of brake fluid leakage in the braking system.

[0003] In recent years, with the vigorous development of automobiles towards electrification, intelligence, and networking; on the one hand, the proportion of electronic automobile parts continues to increase, and the brake system, as a key subsystem of the automobile, has also been gradually replaced by the electronic power-assisted braking solution from the traditional vacuum power-assisted solution. The electronic brake booster Ebooster, unlike the vacuum booster, integrates signals such as the brake pedal stroke and power-assisted current, providing greater possibilities for creating new functions. On the other hand, due to the intelligence of vehicles, higher requirements are also placed on the safety of automobiles. The current mainstream braking system uses hydraulic transmission to push the caliper piston; after a long period of use, or the pipeline is damaged by collision, the brake fluid leaks, and the basic braking system gradually loses its braking force; for this kind of fault condition, the current automobile system can only rely on the liquid level sensor in the brake reservoir to monitor and alarm when the brake fluid leaks very seriously, and ordinary drivers cannot predict it in advance, which poses a serious safety hazard.

[0004] Prior art 1 discloses a solution, which places a liquid level sensor in the brake fluid reservoir and connects it to the controller through a hard wire; when the sensor detects that the liquid level is very low, it will actively alarm. The disadvantage of this solution is that it will only alarm when the leakage is very serious and the liquid level is lower than the minimum threshold, which cannot be predicted in advance and poses a great safety hazard. In addition, this solution can only monitor the brake fluid level in the reservoir, and cannot determine the specific leakage location.

[0005] Prior art 2 discloses a solution, which is mainly to place a liquid level closing switch and other sensors, such as temperature and water content detectors, in the brake fluid reservoir; when the brake fluid in the reservoir is abnormal, an alarm will be triggered. The disadvantage of this solution is that the main purpose is only to monitor the amount of brake fluid in the reservoir, and it cannot directly monitor brake fluid leakage, so slow leakage cannot be effectively monitored, and the cost is high due to the coordination of multiple sensors for monitoring. Summary of the invention

[0006] The object of the present invention is to provide a brake system leakage monitoring method to achieve timely and accurate identification of the leakage position in the brake system.

[0007] In order to solve the above technical problems, the present invention provides a technical solution: a brake system leakage monitoring method, which is implemented based on a brake system using an EBbooster electronic booster, in which a brake master cylinder is connected to a first pipeline and a second pipeline is connected to a brake hydraulic control unit, the pipeline between the brake master cylinder and the brake hydraulic control unit constitutes a primary brake circuit, and the pipelines between the brake hydraulic control unit and the left front wheel caliper wheel cylinder, the right front wheel caliper wheel cylinder, the left rear wheel caliper wheel cylinder, and the right rear wheel caliper wheel cylinder constitute a secondary brake circuit;

[0008] The method includes:

[0009] Brake hydraulic parameter collection: real-time collection of the brake hydraulic pressure of the brake master cylinder, the first pipeline, and the second pipeline; and judging whether to proceed with the subsequent brake fluid leakage location judgment process based on the brake hydraulic pressure of the brake master cylinder, the first pipeline, the second pipeline, and the pedal stroke;

[0010] Preliminary judgment of the brake fluid leakage location: According to the brake fluid pressure of the brake master cylinder, the first pipeline, the second pipeline and the pedal stroke, it is judged that the brake fluid leakage location is in the primary brake circuit or the secondary brake circuit;

[0011] Specific judgment on the brake fluid leakage location: when the brake fluid leakage location determined in the preliminary judgment on the brake fluid leakage location is located in the primary brake circuit, the brake fluid leakage location is determined to be located in the brake master cylinder, the first pipeline, the second pipeline, and the pedal stroke. The brake fluid leakage location is determined to be located in the brake master cylinder, the first pipeline, the second pipeline, and the pedal stroke. When the brake fluid leakage location determined in the preliminary judgment on the brake fluid leakage location is the secondary brake circuit, and the current driving road surface is a homogeneous road surface, the brake fluid leakage location is determined to be located in the left front wheel caliper wheel cylinder, the right front wheel caliper wheel cylinder, the left rear wheel caliper wheel cylinder, or the right rear wheel caliper wheel cylinder according to the left front wheel speed, the right front wheel speed, the left rear wheel speed, and the right rear wheel speed.

[0012] According to the above scheme, the process of determining whether to perform the subsequent brake fluid leakage position determination process according to the brake fluid pressure of the brake master cylinder, the first pipeline, the second pipeline and the pedal stroke is as follows:

[0013] During braking, the EBbooster controller in the EBbooster electronic booster obtains the target brake hydraulic pressure PS according to the pedal travel signal. tar The brake hydraulic pressures of the master cylinder, the first pipeline, and the second pipeline are PS １ , PS2, PS3, find PS １ , PS2, PS3 average , and calculate PS tar and The difference ΔPS;

[0014] When ΔPS≥0, the subsequent brake fluid leakage position determination process is enabled, otherwise the brake fluid pressures of the brake master cylinder, the first pipeline, and the second pipeline are continuously collected and ΔPS is calculated.

[0015] According to the above scheme, the preliminary judgment process of the brake fluid leakage location is as follows:

[0016] If ΔPS≤MAX{αbar,β%×PS tar}, it is judged that the brake fluid leakage position is located in the secondary brake circuit, otherwise it is judged that the brake fluid leakage position is located in the primary brake circuit; wherein α is the preset pressure value, and β is the preset percentage value.

[0017] According to the above scheme, when it is determined that the brake fluid leakage position is located in the primary brake circuit, the specific judgment process of the brake fluid leakage position is as follows:

[0018] Calculate PS respectively tar The differences with PS1, PS2, PS3 are ΔPS1, ΔPS2, ΔPS3;

[0019] If both meet

[0020] ΔPS １ >MAX{αbar,β%×PS tar}

[0021] ΔPS2>MAX{αbar,β%×PS tar}

[0022] ΔPS3>MAX{αbar,β%×PS tar}

[0023] Then the leakage location is judged to be the brake master cylinder;

[0024] If both meet

[0025] ΔPS １ <MAX{αbar,β%×PS tar}

[0026] ΔPS2>MAX{αbar,β%×PS tar}

[0027] ΔPS3<MAX{αbar,β%×PS tar}

[0028] Then it is determined that the leakage location is the first pipeline;

[0029] If both meet

[0030] ΔPS1<MAX{αbar,β%×PStar}

[0031] ΔPS2<MAX{αbar,β%×PS tar}

[0032] ΔPS3>MAX{αbar,β%×PS tar}

[0033] It is determined that the leakage location is the second pipeline.

[0034] According to the above scheme, the mean road surface judgment method is specifically as follows:

[0035] When it is determined that the brake fluid leakage position is located in the second-stage brake circuit, the specific judgment process of the brake fluid leakage position is as follows:

[0036] Collect the left front wheel speed ω FL , right front wheel speedω FR 、Left rear wheel speedω RL 、Right rear wheel speedω RR , calculate the left front wheel deceleration Right front wheel deceleration Left rear wheel deceleration Right rear wheel deceleration Get the average of the two front wheel decelerations and the average of the two rear wheel decelerations

[0037] If both are satisfied,

[0038]

[0039]

[0040]

[0041]

[0042] The current driving road surface is judged to be a homogeneous road surface; wherein γ is a preset percentage value.

[0043] According to the above scheme, when it is determined that the brake fluid leakage position is located in the secondary brake circuit and the current driving road surface is a homogeneous road surface, the specific judgment process of the brake fluid leakage position is as follows:

[0044] Select several braking actions with target brake fluid pressure within a certain threshold under normal braking conditions and driving on homogeneous road conditions, and take the average of the four-wheel deceleration corresponding to the selected several braking actions according to the left front wheel, right front wheel, left rear wheel, and right rear wheel, and get Then there is,

[0045]

[0046]

[0047] If both meet

[0048]

[0049]

[0050]

[0051]

[0052] The leak is determined to be at the left front wheel caliper cylinder; if both

[0053]

[0054]

[0055]

[0056]

[0057] The leak position is determined to be the wheel cylinder of the right front wheel caliper;

[0058] If both meet

[0059]

[0060]

[0061]

[0062]

[0063] The leak location is determined to be the left rear wheel caliper wheel cylinder;

[0064] If both meet

[0065]

[0066]

[0067]

[0068]

[0069] The leak position is determined to be the wheel cylinder of the right rear wheel caliper;

[0070] Where ε and μ are preset percentage values.

[0071] A brake system with a leakage monitoring function for implementing the above-mentioned brake system leakage monitoring method comprises a brake pedal, an EBbooster electronic booster, a brake master cylinder, a brake hydraulic control unit, a left front wheel caliper wheel cylinder, a right front wheel caliper wheel cylinder, a left rear wheel caliper wheel cylinder, a right rear wheel caliper wheel cylinder, a first brake pressure sensor, a second brake pressure sensor, a third brake pressure sensor and wheel speed sensors arranged on four wheels;

[0072] The EBbooster electronic booster includes an input push rod, a travel sensor, an EBbooster controller and a boost motor; the brake pedal is transmission-connected to the input push rod, the travel sensor is arranged on the input push rod and is electrically connected to the EBbooster controller, and the boost motor is electrically connected to the EBbooster controller;

[0073] The power-assisting motor is connected to the piston of the brake master cylinder through a first pipeline and a second pipeline, and the brake hydraulic control unit is connected to the left front wheel caliper wheel cylinder, the right front wheel caliper wheel cylinder, the left rear wheel caliper wheel cylinder, and the right rear wheel caliper wheel cylinder through pipelines, respectively; wherein, the pipeline between the brake master cylinder and the brake hydraulic control unit constitutes a primary brake circuit, and the pipeline between the brake hydraulic control unit and the left front wheel caliper wheel cylinder, the right front wheel caliper wheel cylinder, the left rear wheel caliper wheel cylinder, and the right rear wheel caliper wheel cylinder constitutes a secondary brake circuit;

[0074] The first brake pressure sensor is arranged in the brake master cylinder, the second brake pressure sensor is arranged in the first pipeline, and the third brake pressure sensor is arranged in the second pipeline; the first, second and third brake pressure sensors are all electrically connected to the EBbooster electronic booster;

[0075] The wheel speed sensor is electrically connected to the EBbooster electronic booster;

[0076] The first brake pressure sensor, the second brake pressure sensor, and the third brake pressure sensor are used to collect the brake hydraulic pressure PS1, PS2, and PS3 of the brake master cylinder, the first pipeline, and the second pipeline, respectively;

[0077] The wheel speed sensor is used to collect the left front wheel speed ω FL , right front wheel speedω FR 、Left rear wheel speedω RL 、Right rear wheel speedω RR ;

[0078] The EBbooster controller obtains the target brake fluid pressure PS through the pedal travel signal of the travel sensor. tar, and combined with PS1, PS2, PS3, ω FL ,ω FR ,ω RL ,ω RR Determine whether there is a brake fluid leak and the specific location of the brake fluid leak.

[0079] A computer comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned brake system leakage monitoring method when executing the computer program.

[0080] A computer-readable storage medium stores a computer program, which implements the steps of the above-mentioned brake system leakage monitoring method when executed by a processor.

[0081] A vehicle is provided with the above-mentioned brake system with leakage monitoring function.

[0082] The beneficial effects of the present invention are: by monitoring the brake fluid pressure and wheel speed at different positions in the brake system, it is possible to determine whether the vehicle has a risk of brake fluid leakage and the specific location of the brake fluid leakage. Compared with the prior art, the judgment of brake fluid leakage is more timely and accurate, and can help the owner or maintenance personnel quickly confirm the fault location. The sensors required by the method are all sensors owned by the vehicle, and the calculation control is realized through the EBbooster controller, without adding additional hardware costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 is a schematic diagram of a brake system with a leakage monitoring function according to an embodiment of the present invention;

[0084] Figure 2 4 is a diagram showing a corresponding relationship between a pedal travel signal and a target brake hydraulic pressure according to an embodiment of the present invention. DETAILED DESCRIPTION

[0085] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0086] A brake system leakage monitoring method, the method is implemented based on a brake system using an EBbooster electronic booster, in which a brake master cylinder is connected to a first pipeline and a second pipeline is connected to a brake hydraulic control unit, the pipeline between the brake master cylinder and the brake hydraulic control unit constitutes a primary brake circuit, and the pipelines between the brake hydraulic control unit and a left front wheel caliper wheel cylinder, a right front wheel caliper wheel cylinder, a left rear wheel caliper wheel cylinder, and a right rear wheel caliper wheel cylinder constitute a secondary brake circuit;

[0087] The method comprises the following steps:

[0088] S1, real-time collection of brake hydraulic pressure PS1, PS2, PS3 of the brake master cylinder, the first pipeline, and the second pipeline;

[0089] S2: During braking, the EBbooster controller in the EBbooster electronic booster obtains the target brake hydraulic pressure PS according to the pedal travel signal. tar ; Find the mean of PS1, PS2, and PS3 And calculate PS tar and The difference ΔPS;

[0090]

[0091] When ΔPS ≥ 0, the subsequent brake fluid leakage position determination process is enabled; otherwise, the process returns to S1;

[0092] S3, if ΔPS≤MAX{1bar, 1%×PS tar}, it is determined that the primary brake circuit is normal, and S5 is executed; otherwise, it is determined that there is a leak in the primary brake circuit, and S4 is executed;

[0093] S4. Calculate PS respectively tar The differences with PS1, PS2, PS3 are ΔPS1, ΔPS2, ΔPS3;

[0094] If both meet

[0095] ΔPS1>MAX{1bar, 1%×PS tar}

[0096] ΔPS2>MAX{1bar, 1%×PS tar}

[0097] ΔPS3>MAX{1bar, 1%×PS tar}

[0098] Then the leakage location is judged to be the brake master cylinder;

[0099] If both meet

[0100] ΔPS1<MAX{1bar, 1%×PS tar}

[0101] ΔPS2>MAX{1bar, 1%×PS tar}

[0102] ΔPS3<MAX{1bar, 1%×PS tar}

[0103] Then it is determined that the leakage location is the first pipeline;

[0104] If both meet

[0105] ΔPS1<MAX{1bar, 1%×PS tar}

[0106] ΔPS2<MAX{1bar, 1%×PS tar}

[0107] ΔPS3>MAX{1bar, 1%×PS tar}

[0108] Then it is determined that the leakage location is the second pipeline;

[0109] S5. If the current braking condition is a normal braking condition (and the vehicle's stability control function ABS or AYC is in a non-triggered state, and the braking condition is obtained by the EBbooster controller through the electronic power assist mode in its program), and the current driving road surface is a homogeneous road surface, then proceed to the subsequent steps; the current driving road surface judgment is specifically:

[0110] Collect the left front wheel speed ω FL , right front wheel speedω FR 、Left rear wheel speedω RL 、Right rear wheel speedω RR , calculate the left front wheel deceleration Right front wheel deceleration Left rear wheel deceleration Right rear wheel deceleration Get the average of the two front wheel decelerations and the average of the two rear wheel decelerations

[0111] If both are satisfied,

[0112]

[0113]

[0114]

[0115]

[0116] It is judged that the current driving road surface is a homogeneous road surface;

[0117] S6. Select three braking actions with target brake fluid pressure in the range of (25 bar, 50 bar) under the condition of normal braking condition and driving on homogeneous road surface, and take the average of the four-wheel deceleration corresponding to the three selected braking actions according to the left front wheel, right front wheel, left rear wheel, and right rear wheel, and obtain Then there is,

[0118]

[0119]

[0120] If both meet

[0121]

[0122]

[0123]

[0124]

[0125] The leak is determined to be at the left front wheel caliper cylinder; if both

[0126]

[0127]

[0128]

[0129]

[0130] The leak is judged to be at the right front wheel caliper cylinder; if both

[0131]

[0132]

[0133]

[0134]

[0135] The leak location is determined to be the left rear wheel caliper wheel cylinder;

[0136] If both meet

[0137]

[0138]

[0139]

[0140]

[0141] The leakage location is determined to be the right rear wheel caliper wheel cylinder.

[0142] See also Figure 1 , a brake system with a leakage monitoring function for implementing the above-mentioned brake system leakage monitoring method, comprising a brake pedal, an EBbooster electronic booster, a brake master cylinder, a brake hydraulic control unit, a left front wheel caliper wheel cylinder, a right front wheel caliper wheel cylinder, a left rear wheel caliper wheel cylinder, a right rear wheel caliper wheel cylinder, a first brake pressure sensor, a second brake pressure sensor, a third brake pressure sensor and wheel speed sensors arranged on four wheels;

[0143] The EBbooster electronic booster includes an input push rod, a travel sensor, an EBbooster controller and a boost motor; the brake pedal is transmission-connected to the input push rod, the travel sensor is arranged on the input push rod and is electrically connected to the EBbooster controller, and the boost motor is electrically connected to the EBbooster controller;

[0144] The power-assisting motor is connected to the piston of the brake master cylinder through a first pipeline and a second pipeline, and the brake hydraulic control unit is connected to the left front wheel caliper wheel cylinder, the right front wheel caliper wheel cylinder, the left rear wheel caliper wheel cylinder, and the right rear wheel caliper wheel cylinder through pipelines, respectively; wherein, the pipeline between the brake master cylinder and the brake hydraulic control unit constitutes a primary brake circuit, and the pipeline between the brake hydraulic control unit and the left front wheel caliper wheel cylinder, the right front wheel caliper wheel cylinder, the left rear wheel caliper wheel cylinder, and the right rear wheel caliper wheel cylinder constitutes a secondary brake circuit;

[0145] The first brake pressure sensor is arranged in the brake master cylinder, the second brake pressure sensor is arranged in the first pipeline, and the third brake pressure sensor is arranged in the second pipeline; the first, second and third brake pressure sensors are all electrically connected to the EBbooster electronic booster;

[0146] The wheel speed sensor is electrically connected to the EBbooster electronic booster;

[0147] The first brake pressure sensor, the second brake pressure sensor, and the third brake pressure sensor are used to collect the brake hydraulic pressure PS1, PS2, and PS3 of the brake master cylinder, the first pipeline, and the second pipeline, respectively;

[0148] The wheel speed sensor is used to collect the left front wheel speed ω FL , right front wheel speedωFR 、Left rear wheel speedω RL 、Right rear wheel speedω RR ;

[0149] The EBbooster controller obtains the target brake fluid pressure PS through the pedal travel signal of the travel sensor. tar , and combined with PS1, PS2, PS3, ω FL ,ω FR ,ω RL ,ω RR Determine whether there is a brake fluid leak and the specific location of the brake fluid leak.

[0150] A computer comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned brake system leakage monitoring method when executing the computer program.

[0151] A computer-readable storage medium stores a computer program, which implements the steps of the above-mentioned brake system leakage monitoring method when executed by a processor.

[0152] A vehicle is provided with the above-mentioned brake system with leakage monitoring function.

[0153] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A brake system leakage monitoring method, characterized in that: The method is applicable to the braking system of an EBbooster electronic booster, in which a brake master cylinder is connected to a first pipeline and a second pipeline is connected to a brake hydraulic control unit, the pipeline between the brake master cylinder and the brake hydraulic control unit constitutes a primary braking circuit, and the pipelines between the brake hydraulic control unit and a left front wheel caliper wheel cylinder, a right front wheel caliper wheel cylinder, a left rear wheel caliper wheel cylinder, and a right rear wheel caliper wheel cylinder constitute a secondary braking circuit; The method includes: Collect the brake fluid pressure of the master cylinder, the first pipeline, and the second pipeline in real time; and determine whether to perform the subsequent brake fluid leakage position determination process according to the brake fluid pressure of the master cylinder, the first pipeline, the second pipeline, and the pedal stroke; According to the brake fluid pressures of the brake master cylinder, the first pipeline, the second pipeline, and the pedal stroke, it is determined that the brake fluid leakage position is located in the primary brake circuit or the secondary brake circuit; When it is determined that the brake fluid leakage position is located in the primary brake circuit, the brake fluid leakage position is determined to be located in the brake master cylinder, the first pipeline, the second pipeline, and the brake fluid leakage position is determined to be located in the brake master cylinder, the first pipeline, the second pipeline, and the brake fluid leakage position is determined to be located in the brake master cylinder, the first pipeline, or the second pipeline according to the brake fluid fluid leakage position and the brake fluid fluid leakage position and the pedal stroke; when it is determined that the brake fluid leakage position is located in the secondary brake circuit and the current driving road surface is a homogeneous road surface, the brake fluid leakage position is determined to be located in the left front wheel caliper wheel cylinder, the right front wheel caliper wheel cylinder, the left rear wheel caliper wheel cylinder, or the right rear wheel caliper wheel cylinder according to the left front wheel speed, the right front wheel speed, the left rear wheel speed, and the right rear wheel speed; The specific process of determining whether to proceed with the subsequent brake fluid leakage position determination process according to the brake fluid pressure of the brake master cylinder, the first pipeline, the second pipeline, and the pedal stroke is as follows: During braking, the EBbooster controller in the EBbooster electronic booster obtains the target brake hydraulic pressure PS according to the pedal travel signal. tar ; The brake hydraulic pressures of the brake master cylinder, the first pipeline, and the second pipeline are PS1, PS2, and PS3 respectively. Calculate the average of PS1, PS2, and PS3 And calculate PS tar and The difference ΔPS; When ΔPS ≥ 0, the subsequent brake fluid leakage position determination process is activated, otherwise the brake fluid pressure of the brake master cylinder, the first pipeline, and the second pipeline is continuously collected and ΔPS is calculated; The initial determination process of the brake fluid leakage location is as follows: If ΔPS≤MAX{αbar,β%×PS tar }, it is determined that the brake fluid leakage position is located in the secondary brake circuit, otherwise it is determined that the brake fluid leakage position is located in the primary brake circuit; wherein α is a preset pressure value, and β is a preset percentage value; When it is determined that the brake fluid leakage position is located in the primary brake circuit, the specific judgment process of the brake fluid leakage position is as follows: Calculate PS respectively tar The differences with PS1, PS2, PS3 are ΔPS1, ΔPS2, ΔPS3; If both meet ΔPS1>MAX{αbar,β%×PS tar } ΔPS2>MAX{αbar,β%×PS tar } ΔPS3>MAX{αbar,β%×PS tar } Then the leakage location is judged to be the brake master cylinder; If both meet ΔPS1<MAX{αbar,β%×PS tar } ΔPS2>MAX{αbar,β%×PS tar } ΔPS3<MAX{αbar,β%×PS tar } Then it is determined that the leakage location is the first pipeline; If both meet ΔPS1<MAX{αbar,β%×PS tar } ΔPS2 <MAX{αbar,β%×PS tar } ΔPS3>MAX{αbar,β%×PS tar } It is determined that the leakage location is the second pipeline.

2. The brake system leakage monitoring method according to claim 1, characterized in that: The specific method for judging the mean road surface is: When it is determined that the brake fluid leakage position is located in the second-stage brake circuit, the specific judgment process of the brake fluid leakage position is as follows: Collect the left front wheel speed ω FL , right front wheel speedω FR 、Left rear wheel speedω RL 、Right rear wheel speedω RR , calculate the left front wheel deceleration Right front wheel deceleration Left rear wheel deceleration Right rear wheel deceleration Get the average of the two front wheel decelerations and the average of the two rear wheel decelerations If both are satisfied, The current driving road surface is judged to be a homogeneous road surface; wherein γ is a preset percentage value.

3. The brake system leakage monitoring method according to claim 1, characterized in that: When it is determined that the brake fluid leakage position is located in the secondary brake circuit and the current driving road surface is a homogeneous road surface, the specific judgment process of the brake fluid leakage position is as follows: Select several braking actions with target brake fluid pressure within a certain threshold under normal braking conditions and driving on homogeneous road conditions, and take the average of the four-wheel deceleration corresponding to the selected several braking actions according to the left front wheel, right front wheel, left rear wheel, and right rear wheel, and get Then there is, If both meet The leak is determined to be at the left front wheel caliper cylinder; if both The leak is judged to be at the right front wheel caliper cylinder; if both The leak location is determined to be the left rear wheel caliper wheel cylinder; If both meet The leak position is determined to be the wheel cylinder of the right rear wheel caliper; Where ε and μ are preset percentage values.

4. A brake system with leakage monitoring function for implementing the brake system leakage monitoring method according to any one of claims 1 to 3, characterized in that: It includes a brake pedal, an EBbooster electronic booster, a brake master cylinder, a brake hydraulic control unit, a left front wheel caliper wheel cylinder, a right front wheel caliper wheel cylinder, a left rear wheel caliper wheel cylinder, a right rear wheel caliper wheel cylinder, a first brake pressure sensor, a second brake pressure sensor, a third brake pressure sensor, and wheel speed sensors arranged on four wheels; The EBbooster electronic booster includes an input push rod, a travel sensor, an EBbooster controller and a boost motor; the brake pedal is transmission-connected to the input push rod, the travel sensor is arranged on the input push rod and is electrically connected to the EBbooster controller, and the boost motor is electrically connected to the EBbooster controller; The power-assisting motor is connected to the piston of the brake master cylinder through a first pipeline and a second pipeline, and the brake hydraulic control unit is connected to the left front wheel caliper wheel cylinder, the right front wheel caliper wheel cylinder, the left rear wheel caliper wheel cylinder, and the right rear wheel caliper wheel cylinder through pipelines, respectively; wherein, the pipeline between the brake master cylinder and the brake hydraulic control unit constitutes a primary brake circuit, and the pipeline between the brake hydraulic control unit and the left front wheel caliper wheel cylinder, the right front wheel caliper wheel cylinder, the left rear wheel caliper wheel cylinder, and the right rear wheel caliper wheel cylinder constitutes a secondary brake circuit; The first brake pressure sensor is arranged in the brake master cylinder, the second brake pressure sensor is arranged in the first pipeline, and the third brake pressure sensor is arranged in the second pipeline; the first, second and third brake pressure sensors are all electrically connected to the EBbooster electronic booster; The wheel speed sensor is electrically connected to the EBbooster electronic booster; The first brake pressure sensor, the second brake pressure sensor, and the third brake pressure sensor are used to collect the brake hydraulic pressure PS1, PS2, and PS3 of the brake master cylinder, the first pipeline, and the second pipeline, respectively; The wheel speed sensor is used to collect the left front wheel speed ω FL , right front wheel speedω FR 、Left rear wheel speedω RL 、Right rear wheel speedω RR ; The EBbooster controller obtains the target brake fluid pressure PS through the pedal travel signal of the travel sensor. tar , and combined with PS1, PS2, PS3, ω FL ,ω FR ,ω RL ,ω RR Determine whether there is a brake fluid leak and the specific location of the brake fluid leak.

5. A computer comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the brake system leakage monitoring method according to any one of claims 1-3 are implemented.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the brake system leakage monitoring method according to any one of claims 1 to 3 are implemented.

7. A car, characterized in that: The brake system has the leakage monitoring function as claimed in claim 4.

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