A fuel line leak detection method and related apparatus

Abstract

The application provides a fuel path leakage detection method and related device, and relates to the technical field of detection. After the engine is stopped, a cut-off valve arranged in a low-pressure fuel path is closed to build high-pressure and low-pressure closed oil cavities. By collecting pressure drop values of the two cavities within a preset time period and comprehensively judging in combination with respective corresponding pressure drop threshold ranges, full coverage of leakage detection of the high-pressure and low-pressure fuel paths can be realized, and different leakage types and leakage causes can be accurately distinguished, so that the accuracy and comprehensiveness of the fuel path leakage detection are improved.

Description

Technical Field

[0001] This application relates to the field of detection technology, and in particular to a method and related apparatus for detecting fuel leaks. Background Technology

[0002] In an engine's fuel injection system, the injector is responsible for spraying high-pressure fuel into the combustion chamber in a mist form. To ensure the safe and reliable operation of the engine, the sealing integrity of the fuel lines is crucial. If fuel leaks from the injector chamber into the cylinder head chamber and enters the oil pan, it mixes with the engine oil, causing a decrease in oil viscosity, which can lead to serious engine failures such as cylinder scoring and bearing damage. Summary of the Invention

[0003] In view of the above problems, this application provides a fuel system leak detection method and related apparatus to improve the accuracy and comprehensiveness of fuel system leak detection. The specific solution is as follows:

[0004] The first aspect of this application provides a method for detecting fuel line leaks, including:

[0005] In response to engine shutdown, the control shut-off valve is closed, the shut-off valve being located in the low-pressure fuel circuit;

[0006] Obtain the high pressure drop value of the high pressure fuel circuit and the low pressure drop value of the low pressure fuel circuit within a preset target time period;

[0007] Based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range, the fuel leakage result and the cause of the leakage are determined. The fuel leakage result indicates whether there is a fuel leak and the cause of the leak. The high pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leak in the high pressure fuel circuit under the current operating conditions, and the low pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leak in the low pressure fuel circuit under the current operating conditions.

[0008] In one possible implementation, the fuel leakage result is determined based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range, including:

[0009] If the high pressure drop value is greater than the upper limit of the high pressure drop threshold range, then the fuel leakage result indicates that there is a leak in the high pressure fuel circuit;

[0010] Based on the relationship between the low pressure drop value and the low pressure drop threshold range, the cause of the leak is determined.

[0011] In one possible implementation, the cause of the leak is determined based on the relationship between the low-pressure drop value and the low-pressure drop threshold range, including:

[0012] If the low pressure drop value is less than the lower limit of the low pressure drop threshold range, the cause of leakage may include fuel injector solenoid valve sticking.

[0013] If the low pressure drop value is within the low pressure drop threshold range, the cause of the leak is determined to be a failure of the seal at the connection between the injector and the high-pressure fuel line.

[0014] In one possible implementation, the fuel leakage result is determined based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range, including:

[0015] If the high pressure drop value is within the high pressure drop threshold range, and the low pressure drop value is greater than the upper limit of the low pressure drop threshold range, then the fuel leakage result indicates that there is a leak in the low pressure fuel circuit.

[0016] Based on the pressure data of the low-pressure fuel circuit and the pressure data of the high-pressure fuel circuit during engine operation, the cause of the leak is determined.

[0017] In one possible implementation, the cause of the leak is determined based on pressure data from the low-pressure fuel circuit and pressure data from the high-pressure fuel circuit during engine operation, including:

[0018] Acquire low-pressure and high-pressure data;

[0019] The low-pressure data and the high-pressure data are obtained and cached by monitoring the pressure of the low-pressure fuel circuit and the high-pressure fuel circuit respectively during engine operation.

[0020] Based on the low-pressure data and the high-pressure data, the actual operating pressure value of the high-pressure fuel circuit during operation and the actual operating pressure value of the low-pressure fuel circuit during operation are determined.

[0021] If the actual operating pressure value of the high-pressure fuel circuit is within the preset high-pressure operating range, and the actual operating pressure value of the low-pressure fuel circuit is higher than the upper limit of the preset low-pressure operating range, then the cause of leakage is determined to be damage to the injector gasket.

[0022] If the actual operating pressure of the high-pressure fuel circuit is within the high-pressure operating range and the actual operating pressure of the low-pressure fuel circuit is lower than the lower limit of the low-pressure operating range, then the cause of leakage is determined to include damage to the bushing seal.

[0023] The high-pressure operating range refers to the normal fluctuation range of the high-pressure fuel circuit pressure under normal engine operating conditions, and the low-pressure operating range refers to the normal fluctuation range of the low-pressure fuel circuit pressure under normal engine operating conditions.

[0024] In one possible implementation, determining the fuel leakage result based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range further includes:

[0025] If the high-pressure drop value is greater than the upper limit of the high-pressure drop threshold range, and the low-pressure drop value is greater than the upper limit of the low-pressure drop threshold range, then the fuel leak result is determined to be:

[0026] The low-pressure fuel line is leaking, and the cause of the leak includes at least one of the following: damage to the injector gasket or damage to the bushing seal.

[0027] Furthermore, the high-pressure fuel line is leaking, and the cause of the leak may be the failure of the seal at the connection between the injector and the high-pressure fuel line.

[0028] In one possible implementation, determining the fuel leakage result based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range further includes:

[0029] If the preset safety conditions are met, the fuel leakage result indicates that there is no leakage in both the high-pressure fuel circuit and the low-pressure fuel circuit. The safety conditions include that the high-pressure drop value is within the high-pressure drop threshold range and the low-pressure drop value is within the low-pressure drop threshold range.

[0030] A second aspect of this application provides a fuel line leak detection device, comprising:

[0031] A shutdown control unit is used to control a shut-off valve to close in response to engine shutdown, the shut-off valve being located in the low-pressure fuel circuit;

[0032] The pressure drop detection unit is used to acquire the high pressure drop value of the high pressure fuel circuit and the low pressure drop value of the low pressure fuel circuit within a preset target time period.

[0033] The leakage determination unit is used to determine the fuel leakage result and the cause of leakage based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range. The fuel leakage result indicates whether there is a fuel leakage and the cause of leakage. The high pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leakage in the high pressure fuel circuit under the current operating conditions, and the low pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leakage in the low pressure fuel circuit under the current operating conditions.

[0034] A third aspect of this application provides a fuel line leakage detection system, including a controller, a first pressure sensor, a second pressure sensor, and a shut-off valve; wherein the first pressure sensor is disposed in a low-pressure fuel line, the second pressure sensor is disposed in a high-pressure fuel line, and the shut-off valve is disposed in the low-pressure fuel line;

[0035] The controller is communicatively connected to the first pressure sensor, the second pressure sensor, and the shut-off valve, and is used to execute the fuel line leakage detection method of the first aspect or any implementation thereof.

[0036] A fourth aspect of this application provides an electronic device, including at least one processor and a memory connected to the processor, wherein:

[0037] The memory is used to store computer programs;

[0038] The processor is used to execute the computer program so that the electronic device can implement the fuel line leakage detection method of the first aspect or any implementation thereof.

[0039] By utilizing the above technical solution, this application provides a fuel circuit leakage detection method and related device. After the engine is stopped, the shut-off valve installed in the low-pressure fuel circuit is closed to create a closed oil chamber with high pressure and low pressure. By collecting the pressure drop values ​​of the two chambers within a preset time period and combining them with their respective corresponding pressure drop threshold ranges for comprehensive judgment, it can achieve full coverage of leakage detection in both high-pressure and low-pressure fuel circuits, and accurately distinguish different leakage types and causes, thereby improving the accuracy and comprehensiveness of fuel circuit leakage detection. Attached Figure Description

[0040] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the originals and elements are not necessarily drawn to scale.

[0041] Figure 1 This is a schematic diagram of the structure of a fuel line leak detection system provided in this application;

[0042] Figure 2 This is a schematic diagram of the structure of a fuel line leak detection system provided in this application;

[0043] Figure 3 A schematic flowchart of a fuel line leakage detection method provided in this application;

[0044] Figure 4 A flowchart illustrating another fuel line leak detection method provided in this application;

[0045] Figure 5 A flowchart illustrating another fuel line leak detection method provided in this application;

[0046] Figure 6 This application provides a schematic diagram of the specific structure of a fuel line leak detection system;

[0047] Figure 7 A schematic diagram of the specific process for a fuel line leakage detection method provided in this application;

[0048] Figure 8 This is a schematic diagram of the structure of a fuel line leakage detection device provided in this application;

[0049] Figure 9 This is a schematic diagram of the structure of an electronic device provided in this application. Detailed Implementation

[0050] The embodiments of this application are described below with reference to the accompanying drawings. The terminology used in the implementation section of this application is for explaining specific embodiments only and is not intended to limit the scope of this application.

[0051] As will be known to those skilled in the art, with the development of technology and the emergence of new scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0052] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to those processes, methods, products, or apparatuses.

[0053] like Figure 1As shown, in the fuel circuit structure of the top-entry fuel injector, fuel enters from the top surface of the injector, and the high-pressure interface is enclosed within the closed area formed by the engine rocker arm cover 108 and the cylinder head 101. The injector 102 has an internal control structure that adjusts the fuel injection quantity according to the engine power. Excess fuel leaks into the low-pressure fuel chamber formed by the injector 102, injector bushing 103, and cylinder head 101, and returns to the fuel tank via the low-pressure fuel circuit 106. The injector gasket 104 seals the gap between the injector 102 and the cylinder head 101 to prevent high-pressure gas leakage. An O-ring rubber seal 105 seals the gap between the injector bushing 103 and the cylinder head 101 to prevent fuel leakage. The connection between the injector 102 and the high-pressure fuel circuit 107 is located within the closed cavity formed by the rocker arm cover 108 and the cylinder head 101. The injector 102 has an internal solenoid valve 109 for controlling the on / off of high-pressure fuel.

[0054] The above structure contains several potential locations for fuel leaks, as follows:

[0055] Leakage location 1: The injector gasket 104 is damaged, causing high-pressure gas in the cylinder to enter the low-pressure oil chamber, resulting in an abnormal increase in the pressure of the low-pressure chamber.

[0056] Leakage location 2: The O-ring rubber seal 105 is damaged, causing low-pressure fuel to leak into the cylinder head oil chamber and into the oil pan, resulting in an abnormal decrease in the pressure of the low-pressure chamber.

[0057] Leakage location 3: The seal at the connection between injector 102 and high-pressure fuel line 107 failed, causing high-pressure fuel to leak into the low-pressure fuel chamber, resulting in a decrease in pressure in the high-pressure chamber and an increase in pressure in the low-pressure chamber.

[0058] All of the above leaks can cause fuel to enter the oil pan and mix with the engine oil, leading to serious engine malfunctions such as cylinder scoring and bearing failure.

[0059] Leakage location 4: The injector solenoid valve 109 is stuck, causing high-pressure fuel to continuously leak into the low-pressure fuel chamber, resulting in a decrease in the pressure of the high-pressure chamber and an increase in the pressure of the low-pressure chamber, which will lead to a reduction in engine performance.

[0060] To effectively monitor various leakage locations within the high-pressure and low-pressure fuel chambers of the aforementioned fuel injector, this application provides a fuel system leakage detection method. The fuel system leakage detection method of this application embodiment will be described in detail below with reference to the accompanying drawings.

[0061] The fuel line leakage detection method provided in this application embodiment is applied to the controller of a fuel line leakage detection system. Figure 2 This is a schematic diagram of the structure of a fuel line leak detection system provided in this application, as shown below. Figure 2As shown, the fuel line leak detection system 200 includes a controller 201, a shut-off valve 202, a high-pressure sensor 203, and a low-pressure sensor 204.

[0062] In this embodiment, the shut-off valve 202 is located in the low-pressure fuel circuit and is closed under the control of the controller 201 after the engine stops, thereby cutting off the connection between the low-pressure fuel circuit and the fuel tank. The high-pressure sensor 203 is located in the high-pressure fuel circuit and is used to collect the pressure value of the high-pressure fuel circuit. The low-pressure sensor 204 is located in the low-pressure fuel circuit and is used to collect the pressure value of the low-pressure fuel circuit. The controller 201 can be an engine electronic control unit or a separately configured dedicated controller; the following example uses the engine electronic control unit. The controller 201 is communicatively connected to the shut-off valve 202, the high-pressure sensor 203, and the low-pressure sensor 204, and is used to control the opening and closing state of the shut-off valve 202 and receive the pressure data collected by the high-pressure sensor 203 and the low-pressure sensor 204.

[0063] Reference Figure 3 , Figure 3 This is a flowchart illustrating a fuel line leak detection method provided in an embodiment of this application, as shown below. Figure 3 As shown in the embodiments of this application, a data processing method may include steps S301 to S303, which are described in detail below.

[0064] S301, In response to engine shutdown, control the shut-off valve to close.

[0065] In this embodiment, the shut-off valve is located in the low-pressure fuel circuit. Optionally, the shut-off valve is an electromagnetic shut-off valve.

[0066] In this embodiment, when the engine stops, the engine speed is zero. The engine electronic control unit responds to the stop signal and controls the electromagnetic shut-off valve located in the low-pressure fuel circuit to close. After the electromagnetic shut-off valve closes, the connection between the low-pressure fuel circuit and the fuel tank is cut off. Simultaneously, the injectors and injection pump are also shut off, and the fuel inlet and outlet of the high-pressure fuel circuit are cut off. Based on this, a low-pressure closed fuel chamber and a high-pressure closed fuel chamber are formed.

[0067] S302. Obtain the high pressure drop value of the high-pressure fuel circuit and the low pressure drop value of the low-pressure fuel circuit within a preset target time period.

[0068] In this embodiment, after the electromagnetic shut-off valve, injector, and injection pump are closed, the high-pressure fuel circuit and the low-pressure fuel circuit each form a closed fuel chamber. Both chambers are in a static pressure-holding state. If a leak occurs in any chamber or connection, the pressure inside the chamber will change over time. Within a preset target time period after the electromagnetic shut-off valve, injector, and injection pump are closed, the high-pressure drop value of the high-pressure fuel circuit and the low-pressure drop value of the low-pressure fuel circuit represent the degree of pressure change in the corresponding fuel chambers.

[0069] Specifically, during the target time period after the electromagnetic shut-off valve, injector, and injection pump are closed, the engine electronic control unit collects the pressure change of the high-pressure fuel circuit through the high-pressure sensor to obtain the high-pressure pressure drop value, and collects the pressure change of the low-pressure fuel circuit through the low-pressure sensor to obtain the low-pressure pressure drop value.

[0070] S303. Based on the high pressure drop value, low pressure drop value, high pressure drop threshold range, and low pressure drop threshold range, determine the fuel leakage result and the cause of the leakage.

[0071] In this embodiment, the fuel leakage result indicates whether a fuel leak exists and the cause of the leak. Specifically, the high-pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leak in the high-pressure fuel line under the current operating conditions, and the low-pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leak in the low-pressure fuel line under the current operating conditions.

[0072] It should be noted that the high-pressure drop threshold range and the low-pressure drop threshold range are obtained through calibration. Specifically, with the engine normally shut down and no fuel line leaks, after forming closed oil chambers in both the high-pressure and low-pressure fuel lines, multiple sets of high-pressure drop values ​​and low-pressure drop values ​​are collected within a target time period. The fluctuation range of each set of pressure drop values ​​is taken as the high-pressure drop threshold range and the low-pressure drop threshold range, respectively. Optionally, the calibration process is completed before the engine leaves the factory, and the calibrated pressure drop threshold ranges are stored in the controller for use during actual testing.

[0073] Specifically, the engine electronic control unit compares the collected high pressure drop value with the high pressure drop threshold range and the low pressure drop value with the low pressure drop threshold range. Based on the respective ranges of the pressure drop values ​​of the two chambers and the correlation between the pressure drop values ​​of the two chambers, it comprehensively determines whether there is a fuel leak and the specific cause of the leak.

[0074] As can be seen from the above technical solutions, the fuel circuit leakage detection method provided in this application, after the engine is stopped, controls the shut-off valve set in the low-pressure fuel circuit to close, constructing a high-pressure and low-pressure sealed oil chamber. By collecting the pressure drop values ​​of the two chambers within a preset time period and combining them with their respective corresponding pressure drop threshold ranges for comprehensive judgment, it can achieve full coverage of leakage detection in both high-pressure and low-pressure fuel circuits, and accurately distinguish different leakage types and causes, thereby improving the accuracy and comprehensiveness of fuel circuit leakage detection.

[0075] Figure 4 This is a schematic flowchart of a fuel line leakage detection method provided in an embodiment of this application. Figure 4The illustration shows, in one optional embodiment, S303, a specific method for determining the fuel leak result based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range, as shown in the example. Figure 4 As shown, this method includes:

[0076] S401. If the high pressure drop value is greater than the upper limit of the high pressure drop threshold range, then the fuel leak result indicates that there is a leak in the high pressure fuel circuit.

[0077] In this embodiment, when the high pressure drop value exceeds the upper limit of the high pressure drop threshold range, it indicates that the pressure in the high pressure sealed oil chamber drops too quickly within the target time period, exceeding the normal fluctuation range. Based on this, the system determines that there is a leak in the high pressure fuel circuit.

[0078] S402. Determine the relationship between the low-voltage drop value and the low-voltage drop threshold range.

[0079] In this embodiment, based on the determination that there is a leak in the high-pressure fuel circuit, the positional relationship between the low-pressure drop value and the low-pressure drop threshold range is further determined, that is, whether the low-pressure drop value is below the lower limit, within the range, or above the upper limit, in order to determine whether the high-pressure leak affects the low-pressure chamber and the specific cause of the leak.

[0080] S403. If the low pressure drop value is less than the lower limit of the low pressure drop threshold range, the cause of leakage may include the fuel injector solenoid valve sticking.

[0081] In this embodiment, when the low-pressure drop value is less than the lower limit of the low-pressure drop threshold range, it indicates that the pressure in the low-pressure closed oil chamber is increasing instead of decreasing within the target time period. Based on this, it can be determined that the injector solenoid valve is stuck in the open position, causing high-pressure fuel to continuously leak through the solenoid valve into the low-pressure chamber, resulting in a decrease in the high-pressure chamber pressure and an increase in the low-pressure chamber pressure. Therefore, the cause of the leakage is determined to be the stuck injector solenoid valve.

[0082] S404. If the low pressure drop value is within the low pressure drop threshold range, the cause of the leak is determined to be a failure of the seal at the connection between the injector and the high pressure oil pipe.

[0083] In this embodiment, when the low-pressure drop value is within the low-pressure drop threshold range, it indicates that the pressure change in the low-pressure sealed oil chamber is normal, and the high-pressure fuel leakage has not affected the low-pressure chamber. Based on this, it can be determined that the pressure drop in the high-pressure chamber is caused by the direct leakage of high-pressure fuel through the seal failure at the connection between the injector and the high-pressure fuel line. Therefore, the cause of the leakage is determined to be the seal failure at the connection between the injector and the high-pressure fuel line.

[0084] As can be seen from the above technical solutions, the fuel circuit leakage detection method provided in this application embodiment, when it is determined that there is a leak in the high-pressure fuel circuit, can accurately distinguish between two leakage causes: solenoid valve sticking and high-pressure oil pipe connection seal failure by further analyzing the relationship between the low-pressure drop value and the low-pressure drop threshold range. This achieves accurate location and classification of high-pressure side leakage and improves the accuracy of leakage detection.

[0085] It should be noted that S402 to S404 above is a specific method for determining the cause of leakage based on the relationship between the low-pressure drop value and the low-pressure drop threshold range. In other optional embodiments, other specific methods can also be used to determine the cause of leakage based on the relationship between the low-pressure drop value and the low-pressure drop threshold range when the fuel leakage result indicates that there is a leak in the high-pressure fuel circuit. For example, fuzzy logic comprehensive judgment or lookup table method can be used for cause matching.

[0086] Figure 5 This is a schematic flowchart of a fuel line leakage detection method provided in an embodiment of this application. Figure 5 The illustration shows, in one optional embodiment, S303, a specific method for determining the fuel leak result based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range, as shown in the example. Figure 5 As shown, this method includes:

[0087] S501. If the high pressure drop value is within the high pressure drop threshold range and the low pressure drop value is greater than the upper limit of the low pressure drop threshold range, then the fuel leakage result indicates that there is a leak in the low pressure fuel circuit.

[0088] In this embodiment, when the high-pressure drop value is within the high-pressure drop threshold range, it indicates that the pressure change in the high-pressure sealed oil chamber is normal and there is no leakage in the high-pressure fuel circuit. When the low-pressure drop value is greater than the upper limit of the low-pressure drop threshold range, it indicates that the pressure in the low-pressure sealed oil chamber drops too quickly within the target time period, exceeding the normal fluctuation range. Combining the data from both chambers, it is determined that there is no leakage in the high-pressure fuel circuit, but there is leakage in the low-pressure fuel circuit.

[0089] S502, Obtain low-pressure data and high-pressure data.

[0090] In this embodiment, the low-pressure and high-pressure data are obtained and cached by monitoring the low-pressure fuel circuit and high-pressure fuel circuit respectively during engine operation. Since only the presence of leakage in the low-pressure chamber can be determined when the engine is stopped, but it is impossible to distinguish whether the leakage source is from a damaged injector gasket or a damaged bushing seal, it is necessary to call the pressure data cached during operation for auxiliary differentiation.

[0091] It should be noted that the injector gasket is located between the injector and the cylinder head to seal the high-pressure combustion gases, preventing high-pressure gas from entering the low-pressure fuel chamber through the injector mounting hole. If the gasket is damaged, high-pressure gas will continuously seep into the low-pressure fuel chamber, causing the low-pressure fuel circuit pressure to be higher than normal during operation. The bushing seal, taking an O-ring as an example, is located between the injector bushing and the cylinder head to seal the low-pressure fuel circuit and prevent fuel leakage. If the O-ring is damaged, low-pressure fuel will leak through the gap between the injector bushing and the cylinder head to the oil pan, causing the low-pressure fuel circuit pressure to be lower than normal during operation. Based on the above physical mechanism, the direction of pressure deviation in the low-pressure fuel circuit during operation can be used to distinguish between gasket damage and O-ring damage as the causes of leakage.

[0092] S503. Based on the low-pressure data and high-pressure data, determine the actual operating pressure value of the high-pressure fuel circuit during operation and the actual operating pressure value of the low-pressure fuel circuit during operation.

[0093] In this embodiment, pressure data collected during operation is read from the cache to determine the actual operating pressure values ​​of the high-pressure fuel circuit and the low-pressure fuel circuit during operation. The high-pressure operating range refers to the normal fluctuation range of the high-pressure fuel circuit pressure under normal engine operating conditions, and the low-pressure operating range refers to the normal fluctuation range of the low-pressure fuel circuit pressure under normal engine operating conditions.

[0094] It should be noted that the high-pressure and low-pressure operating ranges are obtained through calibration. Specifically, under normal engine operation and fuel line leak-free conditions, multiple sets of pressure data are collected in both the high-pressure and low-pressure fuel lines. The fluctuation range of each set of pressure data is taken as the high-pressure and low-pressure operating ranges, respectively, and stored in the controller as a judgment benchmark.

[0095] Optionally, the actual operating pressure value is obtained by averaging multiple sets of pressure data collected during the operating state. For example, multiple pressure values ​​are continuously collected at a preset sampling frequency during engine operation, and their arithmetic mean is calculated as the actual operating pressure value.

[0096] Optionally, the actual operating pressure value is obtained by taking the median value of multiple pressure data collected during the operation period. For example, multiple pressure values ​​are continuously collected at a preset sampling frequency during engine operation, and the median value is taken after sorting as the actual operating pressure value to eliminate the influence of occasional abnormal fluctuations on the judgment result.

[0097] S504. If the actual operating pressure of the high-pressure fuel circuit is within the preset high-pressure operating range, and the actual operating pressure of the low-pressure fuel circuit is higher than the upper limit of the preset low-pressure operating range, then the cause of the leak is determined to be damage to the injector gasket.

[0098] In this embodiment, when the actual operating pressure of the high-pressure fuel circuit is within the high-pressure operating range, while the actual operating pressure of the low-pressure fuel circuit is higher than the upper limit of the low-pressure operating range, it indicates that high-pressure gas in the cylinder enters the low-pressure fuel chamber through the damaged injector gasket, causing an abnormal increase in the low-pressure chamber pressure during operation. Therefore, the cause of the leak is determined to be a damaged injector gasket.

[0099] S505. If the actual operating pressure of the high-pressure fuel circuit is within the high-pressure operating range and the actual operating pressure of the low-pressure fuel circuit is below the lower limit of the low-pressure operating range, then the cause of the leak is determined to be damage to the O-ring rubber bushing seal.

[0100] In this embodiment, when the actual operating pressure of the high-pressure fuel circuit is within the high-pressure operating range, while the actual operating pressure of the low-pressure fuel circuit is below the lower limit of the low-pressure operating range, it indicates that low-pressure fuel leaks through the damaged O-ring rubber bushing seal into the cylinder head oil chamber and enters the oil pan, causing an abnormal decrease in the low-pressure chamber pressure during operation. Therefore, the cause of the leakage is determined to be damage to the O-ring rubber bushing seal.

[0101] As can be seen from the above technical solutions, the fuel circuit leakage detection method provided in this application, based on the determination of leakage in the low-pressure fuel circuit in the shutdown state, can accurately distinguish between two leakage causes: fuel injector gasket damage and O-ring rubber bushing seal damage by retrieving the pressure data cached in the running state. This achieves precise location of leakage on the low-pressure side and further improves the accuracy of leakage detection.

[0102] It should be noted that S502 to S505 above are specific methods for determining the cause of leakage based on pressure data from the low-pressure fuel circuit and the high-pressure fuel circuit during engine operation. In other optional embodiments, other specific methods can also be used to determine the cause of leakage based on the relationship between the low-pressure drop value and the low-pressure drop threshold range when the fuel leakage result indicates that there is a leak in the low-pressure fuel circuit. For example, trend analysis can be used to determine the direction of pressure deviation, or eigenvalue comparison can be used for pattern recognition to distinguish between two leakage types: gasket damage and bushing seal damage.

[0103] In an optional embodiment, S103, namely, the specific implementation method for determining the fuel leakage result based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range, further includes at least one of the following A1 and A2:

[0104] A1. If the high-pressure drop value is greater than the upper limit of the high-pressure drop threshold range, and the low-pressure drop value is greater than the upper limit of the low-pressure drop threshold range, then the fuel leak result indicates that there is a leak in the low-pressure fuel line, and the cause of the leak includes at least one of the following: damage to the injector gasket or damage to the O-ring rubber bushing seal. Furthermore, there is a leak in the high-pressure fuel line, and the cause of the leak includes seal failure at the connection between the injector and the high-pressure fuel line.

[0105] In this embodiment, when the high-pressure drop exceeds the upper limit of the high-pressure drop threshold range, and the low-pressure drop also exceeds the upper limit of the low-pressure drop threshold range, it indicates that both the high-pressure and low-pressure fuel lines are leaking simultaneously. Specifically, a rapid drop in high-pressure chamber pressure indicates a leak in the high-pressure fuel line, caused by a seal failure at the connection between the injector and the high-pressure fuel line. A rapid drop in low-pressure chamber pressure indicates a leak in the low-pressure fuel line, caused by at least one of the following: damage to the injector gasket or damage to the O-ring rubber bushing seal. This determination allows for the identification of complex fault scenarios where leaks occur simultaneously on both the high-pressure and low-pressure sides.

[0106] A2. If the preset safety conditions are met, the fuel leakage result indicates that there is no leakage in either the high-pressure fuel circuit or the low-pressure fuel circuit.

[0107] In this embodiment, the safety conditions include the high-pressure drop value being within the high-pressure drop threshold range and the low-pressure drop value being within the low-pressure drop threshold range. When the pressure drop values ​​of both chambers are within their respective normal pressure drop ranges, it indicates that both the high-pressure sealed oil chamber and the low-pressure sealed oil chamber are well sealed and there is no fuel leakage.

[0108] In summary, the fuel circuit leakage detection method provided in this application constructs high-pressure and low-pressure sealed oil chambers, collects the pressure drop values ​​of the two chambers, and makes a comprehensive judgment based on their respective corresponding pressure drop threshold ranges. This method can comprehensively cover various leakage types in high-pressure and low-pressure fuel circuits and accurately distinguish different leakage causes, significantly improving the accuracy and comprehensiveness of fuel circuit leakage detection.

[0109] Figure 6 This is a schematic diagram of the specific structure of a fuel line leak detection system provided in an embodiment of this application. The fuel line leak detection system includes a controller ECU and a low-pressure sensor PT1, a high-pressure sensor PT2, an electromagnetic shut-off valve, a fuel injection pump, a fuel injector, and an engine speed sensor that are connected to it in communication.

[0110] like Figure 6 As shown, fuel is delivered from the fuel tank via the fuel pump, and after being filtered by the fuel coarse filter and the fuel fine filter in sequence, it is pressurized by the fuel injection pump and sent into the common rail. The common rail distributes the high-pressure fuel to each injector.

[0111] like Figure 6As shown, the engine speed sensor detects engine speed to determine whether the engine is stopped. The low-pressure sensor PT1 is located in the low-pressure fuel circuit, for example, the low-pressure fuel circuit between the injector return and the fuel tank, and is used to collect the pressure value of the low-pressure fuel circuit. The high-pressure sensor PT2 is located in the high-pressure fuel circuit, for example, the high-pressure fuel circuit between the common rail and the injector, and is used to collect the pressure value of the high-pressure fuel circuit. An electromagnetic shut-off valve is located in the low-pressure fuel circuit and is controlled by the controller to close after the engine stops, cutting off the connection between the low-pressure fuel circuit and the fuel tank, forming a low-pressure closed fuel chamber. The controller is communicatively connected to the engine speed sensor, low-pressure sensor PT1, high-pressure sensor PT2, and electromagnetic shut-off valve, and is used to receive signals collected by each sensor and control the opening and closing state of the electromagnetic shut-off valve.

[0112] based on Figure 6 The system shown, Figure 7 A flowchart illustrating the specific implementation of a fuel line leakage detection method provided in this application embodiment is shown below. Figure 7 As shown, this method includes:

[0113] S701 During normal engine operation, the pressure values ​​of the fuel lines are continuously monitored by the low-pressure sensor and the high-pressure sensor, and the pressure data is cached in a preset storage space.

[0114] In this embodiment, during engine operation, the low-pressure sensor PT1 continuously collects the pressure value of the low-pressure fuel circuit, and the high-pressure sensor PT2 continuously collects the pressure value of the high-pressure fuel circuit. The pressure data is cached in real time in the controller's storage unit.

[0115] S702: In response to engine shutdown, the control shut-off valve closes, and at the same time the injectors and injection pumps close, forming closed fuel chambers for both the high-pressure fuel circuit and the low-pressure fuel circuit.

[0116] In this embodiment, when the engine speed sensor detects that the engine speed is zero, the controller determines that the engine has stopped and controls the electromagnetic shut-off valve to close in response to the stop signal. At the same time, the fuel injector and fuel injection pump are in a closed state, and the high-pressure fuel circuit and the low-pressure fuel circuit each form an independent closed oil chamber.

[0117] S703. Within a preset target time period, the high-pressure drop value is obtained through the high-pressure sensor, and the low-pressure drop value is obtained through the low-pressure sensor.

[0118] In this embodiment, the high-pressure sensor PT2 and the low-pressure sensor PT1 collect the pressure change of their respective fuel circuits within a preset target time period, obtain the high-pressure drop value △P_H and the low-pressure drop value △P_L, and send them to the controller.

[0119] S704. Determine whether the safety conditions are met, namely: L1≤△P_L≤L2 and H1≤△P_H≤H2.

[0120] Wherein, H1 is the first high-pressure drop threshold, representing the lower limit of the high-pressure drop threshold range; H2 is the second high-pressure drop threshold, representing the upper limit of the high-pressure drop threshold range; L1 is the first low-pressure drop threshold, representing the lower limit of the low-pressure drop threshold range; and L2 is the second low-pressure drop threshold, representing the upper limit of the low-pressure drop threshold range.

[0121] S705. If the safety conditions are met, determine the first leak detection result, i.e., there is no leak in either the high-pressure fuel line or the low-pressure fuel line.

[0122] S706. If the safety conditions are not met, determine whether the high-risk conditions are met, i.e., △P_H>H2 and △P_L>L2.

[0123] S707. If the safety conditions are not met, but the high-risk conditions are met, the second leak detection result is determined, that is, there is a leak in the high-pressure fuel line and a leak in the low-pressure fuel line. The cause of the high-pressure fuel line leak is the failure of the seal at the connection between the injector and the high-pressure fuel line, and the cause of the low-pressure fuel line leak is at least one of the following: damage to the injector gasket or damage to the O-ring rubber seal.

[0124] S708. If the safety conditions and the high-risk conditions are not met, determine whether the first high-pressure leakage risk condition is met, i.e., △P_H>H2 and △P_L<L1. If it is met, determine the third leakage detection result, i.e., there is no leakage in the low-pressure chamber and the cause of leakage in the high-pressure chamber is that the injector solenoid valve is stuck.

[0125] S709. If the safety conditions and the high-risk conditions are not met, determine whether the second high-pressure leakage risk condition is met, i.e., △P_H>H2 and L1≤△P_L≤L2. If it is met, determine the fourth leakage detection result, i.e., there is no leakage in the low-pressure chamber and the leakage in the high-pressure chamber is caused by the failure of the seal at the connection between the injector and the high-pressure oil pipe.

[0126] S710. If the safety conditions and the high-risk conditions are not met, determine whether the low-pressure leakage risk conditions are met, i.e., △P_L>L2 and H1≤△P_H≤H2.

[0127] S711. If the safety conditions and high-risk conditions are not met, but the low-pressure leakage risk conditions are met, then the actual operating pressure value PT1 of the high-pressure fuel circuit and the actual operating pressure value PT2 of the low-pressure fuel circuit are determined based on the high-pressure pressure data and low-pressure pressure data cached during operation.

[0128] S712. Determine whether the gasket damage condition is met, i.e., PT1 is within the high-pressure operating range [PT1_L, PT1_H] and PT2 is higher than the upper limit of the low-pressure operating range PT2_H. If the condition is met, determine the fifth leakage detection result, i.e., the leakage cause is gasket damage.

[0129] S713. Determine whether the conditions for seal ring damage are met, i.e., PT1 is within the high-pressure operating range [PT1_L, PT1_H] and PT2 is lower than the lower limit of the low-pressure operating range PT2_L. If the conditions are met, determine the sixth leakage detection result, i.e. the leakage cause is O-ring rubber seal ring damage.

[0130] S714. Output the fuel leak alarm signal corresponding to the fuel leak result based on the fuel leak result.

[0131] In this embodiment, the fuel leak results include the first leak detection result through the sixth leak detection result.

[0132] If the fuel leak result is the first leak detection result, that is, there is no leak in both the high-pressure fuel circuit and the low-pressure fuel circuit, the controller outputs a no-leak indication signal and does not trigger a fuel leak alarm.

[0133] The specific method for outputting the fuel leak alarm signal corresponding to the fuel leak result is as follows:

[0134] If the fuel leakage result is the second leakage detection result, that is, there is a leak in both the high-pressure fuel circuit and the low-pressure fuel circuit, the cause of the high-pressure fuel circuit leak is the failure of the seal at the connection between the injector and the high-pressure fuel line, and the cause of the low-pressure fuel circuit leak is at least one of the following: damage to the injector gasket or damage to the O-ring rubber seal. The controller outputs a first alarm signal, which is used to indicate that there is a leak in both the high-pressure fuel circuit and the low-pressure fuel circuit, and corresponds to their respective causes of leakage.

[0135] If the fuel leakage result is the third leakage detection result, that is, there is no leakage in the low-pressure chamber and the cause of leakage in the high-pressure chamber is that the injector solenoid valve is stuck, the controller outputs a second alarm signal, which is used to indicate that the injector solenoid valve is stuck.

[0136] If the fuel leakage result is the fourth leakage detection result, that is, there is no leakage in the low-pressure chamber and the leakage in the high-pressure chamber is caused by the failure of the seal at the connection between the injector and the high-pressure fuel line, the controller outputs a third alarm signal, which is used to indicate the failure of the seal at the connection between the injector and the high-pressure fuel line.

[0137] If the fuel leak result is the fifth leak detection result, that is, the cause of the leak is damage to the injector gasket, the controller outputs a fourth alarm signal, which is used to indicate the damage to the injector gasket.

[0138] If the fuel leak result is the sixth leak detection result, that is, the cause of the leak is damage to the O-ring rubber seal, the controller outputs the fifth alarm signal, which is used to indicate that the O-ring rubber seal is damaged.

[0139] As can be seen from the above technical solution, the fuel circuit leakage detection method provided in this application continuously caches the pressure data of the two chambers during engine operation, controls the shut-off valve to close after the engine stops to construct a high-pressure and low-pressure sealed oil chamber, and collects the pressure drop values ​​of the two chambers within a preset time period. Based on the comparison relationship between the pressure drop values ​​of the two chambers and their respective pressure drop threshold ranges, a multi-level comprehensive judgment is made, which can accurately identify various fault conditions such as high-pressure fuel circuit leakage, low-pressure fuel circuit leakage, and simultaneous leakage of high and low-pressure fuel circuits. Furthermore, it can distinguish specific leakage causes such as injector solenoid valve sticking, high-pressure fuel pipe connection sealing failure, injector gasket damage, and O-ring rubber seal damage. Thus, it achieves full coverage detection and precise location of fuel circuit leakage of top-injection fuel injectors, improves the accuracy and comprehensiveness of fuel circuit leakage detection, and provides a reliable fault diagnosis basis for engine maintenance.

[0140] The above describes a fuel line leakage detection method and system provided by the embodiments of this application. Other related devices for performing the above fuel line leakage detection method will be described below.

[0141] Please see Figure 8 , Figure 8 This is a schematic diagram of a fuel line leak detection device provided in an embodiment of this application. Figure 8 As shown, the fuel line leak detection device 800 includes:

[0142] A shutdown control unit 801 is used to control a shut-off valve to close in response to an engine shutdown, the shut-off valve being located in the low-pressure fuel circuit;

[0143] The pressure drop detection unit 802 is used to acquire the high pressure drop value of the high pressure fuel circuit and the low pressure drop value of the low pressure fuel circuit within a preset target time period.

[0144] Leakage determination unit 803 is used to determine the fuel leakage result and the cause of leakage based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range. The fuel leakage result indicates whether there is a fuel leak and the cause of the leak. The high pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leak in the high pressure fuel circuit under the current operating conditions, and the low pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leak in the low pressure fuel circuit under the current operating conditions.

[0145] In one possible implementation, when the leakage determination unit determines the fuel leakage result based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range, it is specifically used for:

[0146] If the high pressure drop value is greater than the upper limit of the high pressure drop threshold range, then the fuel leakage result indicates that there is a leak in the high pressure fuel circuit;

[0147] Based on the relationship between the low pressure drop value and the low pressure drop threshold range, the cause of the leak is determined.

[0148] In one possible implementation, when the leakage determination unit determines the cause of a leakage based on the relationship between the low-pressure drop value and the low-pressure drop threshold range, it is specifically used for:

[0149] If the low pressure drop value is less than the lower limit of the low pressure drop threshold range, the cause of leakage may include fuel injector solenoid valve sticking.

[0150] If the low pressure drop value is within the low pressure drop threshold range, the cause of the leak is determined to be a failure of the seal at the connection between the injector and the high-pressure fuel line.

[0151] In one possible implementation, when the leakage determination unit determines the fuel leakage result based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range, it is specifically used for:

[0152] If the high pressure drop value is within the high pressure drop threshold range, and the low pressure drop value is greater than the upper limit of the low pressure drop threshold range, then the fuel leakage result indicates that there is a leak in the low pressure fuel circuit.

[0153] Based on the pressure data of the low-pressure fuel circuit and the pressure data of the high-pressure fuel circuit during engine operation, the cause of the leak is determined.

[0154] In one possible implementation, when the leakage determination unit determines the cause of a leak based on the pressure data of the low-pressure fuel circuit and the pressure data of the high-pressure fuel circuit during engine operation, it is specifically used for:

[0155] Acquire low-pressure and high-pressure data;

[0156] The low-pressure data and the high-pressure data are obtained and cached by monitoring the pressure of the low-pressure fuel circuit and the high-pressure fuel circuit respectively during engine operation.

[0157] Based on the low-pressure data and the high-pressure data, the actual operating pressure value of the high-pressure fuel circuit during operation and the actual operating pressure value of the low-pressure fuel circuit during operation are determined.

[0158] If the actual operating pressure value of the high-pressure fuel circuit is within the preset high-pressure operating range, and the actual operating pressure value of the low-pressure fuel circuit is higher than the upper limit of the preset low-pressure operating range, then the cause of leakage is determined to be damage to the injector gasket.

[0159] If the actual operating pressure of the high-pressure fuel circuit is within the high-pressure operating range and the actual operating pressure of the low-pressure fuel circuit is lower than the lower limit of the low-pressure operating range, then the cause of leakage is determined to include damage to the bushing seal.

[0160] The high-pressure operating range refers to the normal fluctuation range of the high-pressure fuel circuit pressure under normal engine operating conditions, and the low-pressure operating range refers to the normal fluctuation range of the low-pressure fuel circuit pressure under normal engine operating conditions.

[0161] In one possible implementation, when the leakage determination unit determines the fuel leakage result based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range, it is further configured to:

[0162] If the high-pressure drop value is greater than the upper limit of the high-pressure drop threshold range, and the low-pressure drop value is greater than the upper limit of the low-pressure drop threshold range, then the fuel leak result is determined to be:

[0163] The low-pressure fuel line is leaking, and the cause of the leak includes at least one of the following: damage to the injector gasket or damage to the bushing seal.

[0164] Furthermore, the high-pressure fuel line is leaking, and the cause of the leak may be the failure of the seal at the connection between the injector and the high-pressure fuel line.

[0165] In one possible implementation, when the leakage determination unit determines the fuel leakage result based on the high-pressure drop value, the low-pressure drop value, the high-pressure drop threshold range, and the low-pressure drop threshold range, it is further configured to:

[0166] If the preset safety conditions are met, the fuel leakage result indicates that there is no leakage in both the high-pressure fuel circuit and the low-pressure fuel circuit. The safety conditions include that the high-pressure drop value is within the high-pressure drop threshold range and the low-pressure drop value is within the low-pressure drop threshold range.

[0167] This application also provides an electronic device in its embodiments. (See reference...) Figure 9The diagram illustrates a structural schematic of an electronic device suitable for implementing the fuel line leak detection method in the embodiments of this application. The electronic device in the embodiments of this application may include, but is not limited to, fixed terminals such as mobile phones, laptops, PDAs (personal digital assistants), PADs (tablet computers), desktop computers, etc. Figure 9 The electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0168] like Figure 9 As shown, the electronic device may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 901, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 902 or a program loaded from a storage device 908 into a random access memory (RAM) 903. When the electronic device is powered on, the RAM 903 also stores various programs and data required for the operation of the electronic device. The processing unit 901, ROM 902, and RAM 903 are interconnected via a bus 904. An input / output (I / O) interface 905 is also connected to the bus 904.

[0169] Typically, the following devices can be connected to I / O interface 905: input devices 906 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 907 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 908 including, for example, memory cards, hard drives, etc.; and communication devices 909. Communication device 909 allows electronic devices to exchange data via wireless or wired communication with other devices. Although Figure 9 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown. More or fewer devices may be implemented or have instead.

[0170] This application also provides a computer program product, including computer-readable instructions, which, when executed on an electronic device, cause the electronic device to implement any of the fuel line leakage detection methods provided in this application.

[0171] This application also provides a computer-readable storage medium carrying one or more computer programs. When the one or more computer programs are executed by an electronic device, the electronic device can implement any of the fuel line leakage detection methods provided in this application.

[0172] It should also be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. In addition, in the device embodiment drawings provided in this application, the connection relationship between modules indicates that they have a communication connection, which can be implemented as one or more communication buses or signal lines.

[0173] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware, or it can be implemented by special-purpose hardware including application-specific integrated circuits, special-purpose CPUs, special-purpose memory, special-purpose components, etc. Generally, any function performed by a computer program can be easily implemented by corresponding hardware, and the specific hardware structure used to implement the same function can also be diverse, such as analog circuits, digital circuits, or special-purpose circuits. However, for this application, software program implementation is more often the preferred implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a readable storage medium, such as a computer floppy disk, USB flash drive, mobile hard disk, ROM, RAM, magnetic disk, or optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, training equipment, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0174] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product.

[0175] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, training device, or data center to another website, computer, training device, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a training device or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

Claims

1. A method for detecting fuel line leaks, characterized in that, include: In response to engine shutdown, the control shut-off valve is closed, the shut-off valve being located in the low-pressure fuel circuit; Obtain the high pressure drop value of the high pressure fuel circuit and the low pressure drop value of the low pressure fuel circuit within a preset target time period; Based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range, the fuel leakage result and the cause of the leakage are determined. The fuel leakage result indicates whether there is a fuel leak and the cause of the leak. The high pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leak in the high pressure fuel circuit under the current operating conditions, and the low pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leak in the low pressure fuel circuit under the current operating conditions.

2. The method according to claim 1, characterized in that, The determination of the fuel leakage result based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range includes: If the high pressure drop value is greater than the upper limit of the high pressure drop threshold range, then the fuel leakage result indicates that there is a leak in the high pressure fuel circuit; Based on the relationship between the low pressure drop value and the low pressure drop threshold range, the cause of the leak is determined.

3. The method according to claim 2, characterized in that, The determination of the cause of leakage based on the relationship between the low-pressure drop value and the low-pressure drop threshold range includes: If the low pressure drop value is less than the lower limit of the low pressure drop threshold range, the cause of leakage may include fuel injector solenoid valve sticking. If the low pressure drop value is within the low pressure drop threshold range, the cause of the leak is determined to be a failure of the seal at the connection between the injector and the high-pressure fuel line.

4. The method according to claim 1, characterized in that, The determination of fuel leakage results based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range includes: If the high pressure drop value is within the high pressure drop threshold range, and the low pressure drop value is greater than the upper limit of the low pressure drop threshold range, then the fuel leakage result indicates that there is a leak in the low pressure fuel circuit. Based on the pressure data of the low-pressure fuel circuit and the pressure data of the high-pressure fuel circuit during engine operation, the cause of the leak is determined.

5. The method according to claim 4, characterized in that, The determination of the cause of leakage based on the pressure data of the low-pressure fuel circuit and the pressure data of the high-pressure fuel circuit during engine operation includes: Acquire low-pressure and high-pressure data; The low-pressure data and the high-pressure data are obtained and cached by monitoring the pressure of the low-pressure fuel circuit and the high-pressure fuel circuit respectively during engine operation. Based on the low-pressure data and the high-pressure data, the actual operating pressure value of the high-pressure fuel circuit during operation and the actual operating pressure value of the low-pressure fuel circuit during operation are determined. If the actual operating pressure value of the high-pressure fuel circuit is within the preset high-pressure operating range, and the actual operating pressure value of the low-pressure fuel circuit is higher than the upper limit of the preset low-pressure operating range, then the cause of leakage is determined to be damage to the injector gasket. If the actual operating pressure of the high-pressure fuel circuit is within the high-pressure operating range and the actual operating pressure of the low-pressure fuel circuit is lower than the lower limit of the low-pressure operating range, then the cause of leakage is determined to include damage to the bushing seal. The high-pressure operating range refers to the normal fluctuation range of the high-pressure fuel circuit pressure under normal engine operating conditions, and the low-pressure operating range refers to the normal fluctuation range of the low-pressure fuel circuit pressure under normal engine operating conditions.

6. The method according to any one of claims 2 to 5, characterized in that, The determination of the fuel leakage result based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range further includes: If the high-pressure drop value is greater than the upper limit of the high-pressure drop threshold range, and the low-pressure drop value is greater than the upper limit of the low-pressure drop threshold range, then the fuel leak result is determined to be: The low-pressure fuel line is leaking, and the cause of the leak includes at least one of the following: damage to the injector gasket or damage to the bushing seal. Furthermore, the high-pressure fuel line is leaking, and the cause of the leak may be the failure of the seal at the connection between the injector and the high-pressure fuel line.

7. The method according to any one of claims 2 to 5, characterized in that, The determination of the fuel leakage result based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range further includes: If the preset safety conditions are met, the fuel leakage result indicates that there is no leakage in both the high-pressure fuel circuit and the low-pressure fuel circuit. The safety conditions include that the high-pressure drop value is within the high-pressure drop threshold range and the low-pressure drop value is within the low-pressure drop threshold range.

8. A fuel line leak detection device, characterized in that, include: A shutdown control unit is used to control a shut-off valve to close in response to engine shutdown, the shut-off valve being located in the low-pressure fuel circuit; The pressure drop detection unit is used to acquire the high pressure drop value of the high pressure fuel circuit and the low pressure drop value of the low pressure fuel circuit within a preset target time period. The leakage determination unit is used to determine the fuel leakage result and the cause of leakage based on the high pressure drop value, the low pressure drop value, the high pressure drop threshold range, and the low pressure drop threshold range. The fuel leakage result indicates whether there is a fuel leakage and the cause of leakage. The high pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leakage in the high pressure fuel circuit under the current operating conditions, and the low pressure drop threshold range indicates the allowable fluctuation range of the pressure drop value when there is no leakage in the low pressure fuel circuit under the current operating conditions.

9. A fuel line leak detection system, characterized in that, It includes a controller, a first pressure sensor, a second pressure sensor, and a shut-off valve; wherein the first pressure sensor is located in the low-pressure fuel circuit, the second pressure sensor is located in the high-pressure fuel circuit, and the shut-off valve is located in the low-pressure fuel circuit; The controller is communicatively connected to the first pressure sensor, the second pressure sensor, and the shut-off valve, and is used to perform the method as described in any one of claims 1 to 7.

10. An electronic device, characterized in that, It includes at least one processor and a memory connected to the processor, wherein: The memory is used to store computer programs; The processor is used to execute the computer program to enable the electronic device to implement the fuel line leak detection method as described in any one of claims 1 to 7.

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