Vehicle fuel oil leakage detection system, vehicle fuel oil leakage detection method and vehicle

Abstract

The invention provides a vehicle fuel leakage detection system, a vehicle fuel leakage detection method and a vehicle, the vehicle fuel leakage detection system comprises a fuel tank stop valve, a first pressure sensor, a carbon tank desorption valve, a carbon tank stop valve, a gas source and an ECU, and the gas source comprises a gas source stop valve and a gas tank. The fuel tank stop valve is installed in a connecting pipeline of the fuel tank and the carbon tank, the carbon tank desorption valve is installed in a connecting pipeline of the carbon tank and the engine, the carbon tank stop valve is installed on a ventilation pipe of the carbon tank, the first pressure sensor is installed in the fuel evaporation system, and a gas outlet of the gas tank is connected with the fuel evaporation system through the gas source stop valve and a pipeline. The ECU is used for detecting leakage of the fuel evaporation system by controlling the fuel tank stop valve, the first pressure sensor, the carbon tank desorption valve, the carbon tank stop valve and the gas source stop valve. According to the scheme, the vehicle fuel oil leakage detection system is constructed, the ECU is adopted to carry out leakage detection on the fuel oil evaporation system, manual detection is not needed, and the detection efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a vehicle fuel leak detection system, a vehicle fuel leak detection method, and a vehicle. Background Technology

[0002] Hybrid and range-extended vehicles have gained attention due to their lower operating costs. Both types of vehicles incorporate a fuel vaporization system. This system connects the engine, carbon canister, and fuel tank sequentially via piping. Fuel vapor generated in the fuel tank is adsorbed by activated carbon in the carbon canister. Then, when the engine is running, the adsorbed fuel vapor desorbs from the activated carbon and enters the engine, reducing fuel waste. To ensure vehicle safety, fuel leak detection is necessary to determine if there are any leaks in the fuel vaporization system.

[0003] In existing technologies, vehicle fuel leak detection is typically performed manually after the vehicle is powered off. Workers pressurize and then seal the fuel evaporation system, then check for pressure changes to determine if a leak has occurred.

[0004] In summary, existing methods for detecting vehicle fuel leaks rely on manual methods, resulting in low detection efficiency. Summary of the Invention

[0005] The vehicle fuel leak detection system, vehicle fuel leak detection method, and vehicle provided in this application are intended to solve the problem of low detection efficiency caused by manual detection in the prior art.

[0006] In a first aspect, embodiments of this application provide a vehicle fuel leak detection system, including:

[0007] Fuel tank shut-off valve, first pressure sensor, carbon canister desorption valve, carbon canister shut-off valve, air source and electronic control unit (ECU);

[0008] The gas source includes a gas source shut-off valve and a gas cylinder;

[0009] The fuel tank shut-off valve is installed in the connecting pipeline between the fuel tank and the carbon canister, the carbon canister desorption valve is installed in the connecting pipeline between the carbon canister and the engine, the carbon canister shut-off valve is installed in the ventilation pipe of the carbon canister, the first pressure sensor is installed in the fuel evaporation system, and the gas outlet of the gas canister is connected to the fuel evaporation system through the gas source shut-off valve and the pipeline.

[0010] The ECU is electrically connected to the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve, respectively.

[0011] The ECU is used to detect leaks in the fuel evaporation system by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve.

[0012] In one possible implementation, when the ECU is used to detect leaks in the fuel evaporation system by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve, it is specifically used for:

[0013] When the preset leak detection conditions are detected, the system controls the oil tank shut-off valve to open, controls the carbon canister desorption valve to close, controls the carbon canister shut-off valve to close, controls the gas source shut-off valve to open, and monitors the real-time pressure through the first pressure sensor.

[0014] When the real-time pressure is detected to reach the preset target pressure, the gas source shut-off valve is controlled to close.

[0015] Within a second preset time period following a first preset time period, the pressure to be detected is acquired through the first pressure sensor;

[0016] Leak detection is performed on the fuel evaporation system based on all the pressures to be tested.

[0017] In one possible implementation, the ECU, when used to perform leak detection on the fuel evaporation system based on all the pressures to be detected, is specifically used for:

[0018] Generate a pressure change function based on all the pressures to be detected;

[0019] The integral value to be detected is obtained by performing an integral calculation based on the pressure change function;

[0020] If the integral value to be detected is greater than the preset integral threshold, it is determined that a leak has occurred in the fuel evaporation system;

[0021] If the integral value to be detected is less than or equal to the preset integral threshold, it is determined that there is no leak in the fuel evaporation system.

[0022] In one possible implementation, the gas source further includes an air pump, a one-way valve, and a second pressure sensor;

[0023] The air outlet of the air pump is connected to the air inlet of the one-way valve through a pipeline, the air outlet of the one-way valve is connected to the air inlet of the air tank, and the second pressure sensor is installed in the air tank.

[0024] The air pump and the second pressure sensor are electrically connected to the ECU;

[0025] The ECU is also used for:

[0026] When the second pressure sensor detects that the pressure in the air tank is lower than the preset inflation pressure threshold, it controls the air pump to operate.

[0027] When the second pressure sensor detects that the pressure in the gas tank has reached the preset inflation pressure threshold, the air pump is controlled to stop working.

[0028] In one possible implementation, the gas source further includes a dryer;

[0029] The dryer is installed in the connecting pipeline between the air outlet of the air pump and the air inlet of the one-way valve.

[0030] Secondly, embodiments of this application provide a vehicle fuel leak detection method, applied to the ECU in the vehicle fuel leak detection system described in any of the first aspects, the method comprising:

[0031] Leakage detection of the fuel evaporation system is performed by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve.

[0032] In one possible implementation, the leak detection of the fuel evaporation system by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve includes:

[0033] When the preset leak detection conditions are detected, the system controls the oil tank shut-off valve to open, controls the carbon canister desorption valve to close, controls the carbon canister shut-off valve to close, controls the gas source shut-off valve to open, and monitors the real-time pressure through the first pressure sensor.

[0034] When the real-time pressure is detected to reach the preset target pressure, the gas source shut-off valve is controlled to close.

[0035] Within a second preset time period following a first preset time period, the pressure to be detected is acquired through the first pressure sensor;

[0036] Leak detection is performed on the fuel evaporation system based on all the pressures to be tested.

[0037] In one possible implementation, the leak detection of the fuel evaporation system based on all the pressures to be detected includes:

[0038] Calculate the pressure difference between the maximum and minimum values ​​among all the pressures to be detected;

[0039] If the pressure difference is greater than a preset pressure difference threshold, it is determined that a leak has occurred in the fuel evaporation system;

[0040] If the pressure difference is less than or equal to the preset pressure difference threshold, it is determined that there is no leak in the fuel evaporation system.

[0041] In one possible implementation, the leak detection of the fuel evaporation system based on all the pressures to be detected includes:

[0042] Generate a pressure change function based on all the pressures to be detected;

[0043] The integral value to be detected is obtained by performing an integral calculation based on the pressure change function;

[0044] If the integral value to be detected is greater than the preset integral threshold, it is determined that a leak has occurred in the fuel evaporation system;

[0045] If the integral value to be detected is less than or equal to the preset integral threshold, it is determined that there is no leak in the fuel evaporation system.

[0046] In one possible implementation, the preset leak detection conditions include:

[0047] The vehicle is powered off, the engine's cumulative operating time is greater than or equal to the preset operating time threshold, the current ambient temperature is within the preset ambient temperature range, the current fuel tank level is within the preset height range, and the atmospheric pressure at the vehicle's location is less than the preset pressure threshold.

[0048] In one possible implementation, controlling the opening of the gas source shut-off valve includes:

[0049] The gas source shut-off valve is controlled to open according to the preset opening frequency and preset single opening duration.

[0050] In one possible implementation, before controlling the opening of the fuel tank shut-off valve, controlling the closing of the carbon canister desorption valve, controlling the closing of the carbon canister shut-off valve, controlling the opening of the gas source shut-off valve, and monitoring the real-time pressure via the first pressure sensor, the vehicle fuel leak detection method further includes:

[0051] The system controls the opening of the oil tank shut-off valve, the closing of the carbon canister desorption valve, the opening of the carbon canister shut-off valve, and the closing of the gas source shut-off valve, and monitors the pressure relief pressure using the first pressure sensor.

[0052] The control of opening the oil tank shut-off valve, closing the carbon canister desorption valve, closing the carbon canister shut-off valve, opening the gas source shut-off valve, and monitoring real-time pressure via the first pressure sensor includes:

[0053] When the pressure relief reaches the atmospheric pressure at the vehicle's current location, the system controls the opening of the fuel tank shut-off valve, the closing of the carbon canister desorption valve, the closing of the carbon canister shut-off valve, and the opening of the air source shut-off valve, and monitors the real-time pressure through the first pressure sensor.

[0054] In one possible implementation, the vehicle fuel leak detection method further includes:

[0055] The system controls the opening of the oil tank shut-off valve, the closing of the carbon canister desorption valve, the opening of the carbon canister shut-off valve, and the closing of the gas source shut-off valve, and monitors the pressure relief pressure using the first pressure sensor.

[0056] When the pressure relief reaches the atmospheric pressure at the vehicle's current location, the fuel tank shut-off valve is closed.

[0057] Thirdly, embodiments of this application provide a vehicle including the vehicle fuel leak detection system described in any of the first aspects above;

[0058] The ECU in the vehicle fuel leak detection system is used to execute the vehicle fuel leak detection method described in any of the second aspects above.

[0059] This application provides a vehicle fuel leak detection system, a vehicle fuel leak detection method, and a vehicle. The vehicle fuel leak detection system includes a fuel tank shut-off valve, a first pressure sensor, a carbon canister desorption valve, a carbon canister shut-off valve, a gas source, and an ECU. The gas source includes a gas source shut-off valve and a gas canister. The fuel tank shut-off valve is installed in the connection pipeline between the fuel tank and the carbon canister. The carbon canister desorption valve is installed in the connection pipeline between the carbon canister and the engine. The carbon canister shut-off valve is installed in the carbon canister's ventilation pipe. The first pressure sensor is installed in the fuel evaporation system. The gas canister's outlet is connected to the fuel evaporation system through the gas source shut-off valve and pipeline. The ECU is electrically connected to the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve. The ECU is used to detect leaks in the fuel evaporation system by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve. This solution improves detection efficiency by constructing a vehicle fuel leak detection system and using the ECU to detect leaks in the fuel evaporation system, eliminating the need for manual inspection. Attached Figure Description

[0060] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0061] Figure 1 This is a schematic diagram of the fuel evaporation system provided in this application;

[0062] Figure 2Schematic diagram of the vehicle fuel leak detection system provided in this application Figure 1 ;

[0063] Figure 3 Schematic diagram of the process for fuel leak detection of the ECU provided in this application Figure 1 ;

[0064] Figure 4 A schematic diagram of the pressure change function provided in this application;

[0065] Figure 5 Schematic diagram of the process for fuel leak detection of the ECU provided in this application Figure 2 ;

[0066] Figure 6 Schematic diagram of the vehicle fuel leak detection system provided in this application Figure 2 ;

[0067] Figure 7 This is a schematic diagram of the structure of an ECU provided in this application.

[0068] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0069] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0070] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0071] With the continuous development of technology, the types of vehicles are becoming increasingly diverse. Among them, hybrid vehicles and range-extended vehicles have attracted attention due to their lower operating costs. Hybrid and range-extended vehicles incorporate fuel evaporation systems to reduce fuel waste caused by fuel evaporation.

[0072] For example, Figure 1 A schematic diagram of the fuel evaporation system provided in this application is shown below. Figure 1 As shown, the fuel evaporation system includes a fuel tank, a fuel tank shut-off valve, a carbon canister, a carbon canister desorption valve, a connecting line between the carbon canister and the engine, and a connecting line between the fuel tank and the carbon canister. The fuel tank shut-off valve is installed in the connecting line between the fuel tank and the carbon canister, and the carbon canister desorption valve is installed in the connecting line between the carbon canister and the engine.

[0073] When the fuel tank pressure is high, the fuel tank shut-off valve opens, allowing fuel vapor to be adsorbed by the activated carbon in the carbon canister, thus reducing the fuel tank pressure. When the engine is not running, the carbon canister desorption valve closes to prevent fuel vapor from being wasted. When the engine is running, the carbon canister desorption valve opens, and the engine draws gas from the carbon canister, desorbing the fuel adsorbed on the activated carbon, which is then drawn into the engine for combustion.

[0074] To ensure vehicle safety, fuel leak detection is necessary to determine if there is a leak in the fuel evaporation system.

[0075] In existing technologies, vehicle fuel leak detection is typically performed manually after the vehicle is powered off. Workers pressurize and then seal the fuel evaporation system, then check for pressure changes to determine if a leak has occurred. This manual approach results in low detection efficiency.

[0076] To address the problems existing in the prior art, the inventors, during their research on vehicle fuel leak detection systems, discovered that a vehicle fuel leak detection system can be constructed comprising a fuel tank shut-off valve, a first pressure sensor, a carbon canister desorption valve, a carbon canister shut-off valve, a gas source, and an Electronic Control Unit (ECU). The gas source includes a gas source shut-off valve and a gas canister. The fuel tank shut-off valve can be installed in the connection pipeline between the fuel tank and the carbon canister, the carbon canister desorption valve in the connection pipeline between the carbon canister and the engine, the carbon canister shut-off valve in the carbon canister's ventilation pipe, and the first pressure sensor in the fuel evaporation system. The gas canister's outlet is connected to the fuel evaporation system via the gas source shut-off valve and pipeline. The ECU controls the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve to achieve sealing, pressurization, and pressure change detection of the fuel evaporation system, thereby enabling leak detection without manual inspection and improving detection efficiency. Based on the above inventive concept, the vehicle fuel leak detection system of this application was designed.

[0077] The technical solution of this application will now be described in detail through specific embodiments. It should be noted that the following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0078] The following describes the vehicle fuel leak detection system using Embodiment 1 provided in this application.

[0079] For example, Figure 2 Schematic diagram of the vehicle fuel leak detection system provided in this application Figure 1 .like Figure 2 As shown in the diagram, dashed lines represent wiring harnesses, and thicker solid lines represent pipes. This vehicle fuel leak detection system includes:

[0080] Fuel tank shut-off valve 201, first pressure sensor 202, carbon canister desorption valve 203, carbon canister shut-off valve 204, air source 205, and ECU 206.

[0081] The gas source 205 includes a gas source shut-off valve 207 and a gas tank 208.

[0082] Fuel tank shut-off valve 201 is installed in the connecting pipe between fuel tank 209 and carbon canister 210, carbon canister desorption valve 203 is installed in the connecting pipe between carbon canister 210 and engine 211, carbon canister shut-off valve 202 is installed in the ventilation pipe of carbon canister 210, first pressure sensor 202 is installed in the fuel evaporation system, and the outlet of gas canister 208 is connected to the fuel evaporation system through gas source shut-off valve 207 and pipeline.

[0083] ECU206 is electrically connected to fuel tank shut-off valve 201, first pressure sensor 202, carbon canister desorption valve 203, carbon canister shut-off valve 204 and air source shut-off valve 207 respectively.

[0084] It should be noted that the fuel tank shut-off valve 201, carbon canister desorption valve 203, carbon canister shut-off valve 204, and air source shut-off valve 207 are valves that can be controlled to open and close by the ECU 206. They can be electric valves or solenoid valves. This application embodiment does not limit the types of fuel tank shut-off valves, carbon canister desorption valves, carbon canister shut-off valves, and air source shut-off valves, and they can be determined according to the actual situation.

[0085] It should be noted that the first pressure sensor 202 is installed in the fuel evaporation system. It can be installed in the pipeline between the fuel tank 209 and the fuel tank shut-off valve 201, the pipeline between the fuel tank shut-off valve 201 and the carbon canister 210, the pipeline between the carbon canister 210 and the carbon canister shut-off valve 204, the pipeline between the carbon canister 210 and the carbon canister desorption valve 203, or in the carbon canister 210 or the fuel tank 209. The pressure sensor 202 can also be combined with the fuel tank shut-off valve 201. This application embodiment does not limit the installation location of the first pressure sensor; it can be determined according to the actual situation.

[0086] It should be noted that the connection between the outlet of the gas tank 208 and the fuel evaporation system via the gas source shut-off valve 207 and the pipeline means that the outlet of the gas tank 208 is connected to the first end of the gas source shut-off valve 207 via the pipeline, and the second end of the gas source shut-off valve 207 is connected to the fuel evaporation system.

[0087] The second end of the gas source shut-off valve 207 is connected to the fuel evaporation system. It can be connected to the pipeline between the fuel tank 209 and the fuel tank shut-off valve 201, the pipeline between the fuel tank shut-off valve 201 and the carbon canister 210, the pipeline between the carbon canister 210 and the carbon canister shut-off valve 204, the pipeline between the carbon canister 210 and the carbon canister desorption valve 203, the carbon canister 207, or the fuel tank 206. In this embodiment, the connection position between the second end of the gas source shut-off valve 207 and the fuel evaporation system is not limited, and can be determined according to the actual situation.

[0088] ECU206 is used to detect leaks in the fuel evaporation system by controlling the fuel tank shut-off valve 201, the first pressure sensor 202, the carbon canister desorption valve 203, the carbon canister shut-off valve 204, and the gas source shut-off valve 207.

[0089] For example, Figure 3 Schematic diagram of the process for fuel leak detection of the ECU provided in this application Figure 1 .like Figure 3 As shown, ECU206 can detect leaks in the fuel evaporation system by controlling fuel tank shut-off valve 201, first pressure sensor 202, carbon canister desorption valve 203, carbon canister shut-off valve 204, and air supply shut-off valve 207 through the following steps:

[0090] S301: When the preset leak detection condition is detected, the control oil tank shut-off valve is opened, the control carbon canister desorption valve is closed, the control carbon canister shut-off valve is closed, the control air source shut-off valve is opened, and the real-time pressure is monitored by the first pressure sensor.

[0091] In this step, to improve the accuracy of fuel leak detection, the ECU needs to monitor whether the preset leak detection conditions are met. When the preset leak detection conditions are met, the ECU controls the fuel tank shut-off valve to open, the carbon canister desorption valve to close, the carbon canister shut-off valve to close, and the air supply shut-off valve to open, while monitoring the real-time pressure through the first pressure sensor.

[0092] The preset leakage detection conditions include the first condition, the second condition, the third condition, the fourth condition, and the fifth condition.

[0093] The second condition is that the vehicle is powered off.

[0094] The second condition is: the cumulative working time of the engine is greater than or equal to the preset working time threshold.

[0095] The third condition is: the current ambient temperature is within the preset ambient temperature range.

[0096] The fourth condition is: the current liquid level in the tank is within the preset height range.

[0097] The fifth condition is: the atmospheric pressure at the vehicle's location is less than the preset pressure threshold.

[0098] The preset leak detection conditions being met means that all five conditions (first, second, third, fourth, and fifth) are met. The preset leak detection conditions not being met means that at least one of the five conditions is not met.

[0099] It should be noted that the cumulative engine operating time refers to the cumulative engine operating time during the vehicle's journey before the power is switched off.

[0100] It should be noted that the preset working time threshold can be 600 seconds, 610 seconds, 650 seconds, 700 seconds, etc. The preset ambient temperature range can be 4-35℃, 7-32℃, 10-30℃, etc. The liquid level height can be expressed as a percentage, representing the percentage of the actual liquid level height to the actual tank height, and the preset height range can be 15%-85%, 20%-80%, 23%-76%, etc. The preset pressure threshold can be 75kPa, 80kPa, 110kPa, etc. This application embodiment does not limit the preset working time threshold, preset ambient temperature range, preset height range, and preset pressure threshold, which can be determined according to the actual situation.

[0101] Setting preset leak detection conditions can eliminate interference from variables such as temperature, pressure, oil level, and carbon canister desorption, ensuring the accuracy of the detection results.

[0102] It should be noted that if the preset leak detection conditions are not met, fuel leak detection will not be performed.

[0103] By opening the fuel tank shut-off valve, closing the carbon canister desorption valve, closing the carbon canister shut-off valve, and opening the gas supply shut-off valve, the fuel evaporation system can be shut off, and the gas canister can be used to charge the fuel evaporation system.

[0104] It should be noted that when controlling the opening of the gas supply shut-off valve, the ECU can control the valve to open according to a preset opening frequency and a preset single opening duration. The reciprocal of the preset opening frequency is used as the opening cycle duration. The ECU controls the gas supply shut-off valve to open once every opening cycle duration, and closes after each preset single opening duration. Because the pressure in the gas tank is relatively high, controlling the opening of the gas supply shut-off valve according to the preset opening frequency and preset single opening duration can control the charging rate of the gas tank to the fuel evaporation system, reducing the impact of the gas in the gas tank on the fuel evaporation system.

[0105] The preset activation frequency can be 10Hz, 20Hz, 30Hz, etc., and the preset single activation duration can be 0.01 seconds, 0.005 seconds, 0.007 seconds, etc. This application embodiment does not limit the preset activation frequency and the preset single activation duration, which can be determined according to the actual situation.

[0106] S302: When the real-time pressure is detected to reach the preset target pressure, the gas source shut-off valve is closed.

[0107] In this step, when the ECU detects that the real-time pressure has reached the preset target pressure through the first pressure sensor, it needs to control the gas source shut-off valve to close in order to detect subsequent pressure changes and thus shut off the fuel evaporation system.

[0108] It should be noted that when the control air source shut-off valve is closed, the states of the oil tank shut-off valve, carbon canister desorption valve, and carbon canister shut-off valve should remain unchanged.

[0109] It should be noted that the gas pressure in the gas tank is greater than the preset target pressure. The preset target pressure can be 4 kPa, 5 kPa, 6 kPa, etc. This application embodiment does not limit the preset target pressure, and it can be determined according to the actual situation.

[0110] It should be noted that the ECU can monitor whether the real-time pressure reaches the preset target pressure within a preset charging time. If the real-time pressure does not reach the preset target pressure within the preset charging time, it indicates that there are large holes in the fuel evaporation system, confirming a leak in the fuel evaporation system. If the real-time pressure reaches the preset target pressure within the preset charging time, the ECU will control the gas supply shut-off valve to close when the real-time pressure reaches the preset target pressure.

[0111] It should be noted that the preset inflation time can be 10 seconds, 50 seconds, 200 seconds, etc. This application embodiment does not limit the preset inflation time, and it can be determined according to the actual situation.

[0112] S303: Within a second preset time period after the first preset time period, the pressure to be detected is acquired through the first pressure sensor.

[0113] In this step, after the ECU controls the gas supply shut-off valve to close, the vehicle will only stabilize after a period of time, and the fuel leak detection will be more accurate. Therefore, within the second preset time after the first preset time, the pressure to be detected is obtained through the first pressure sensor.

[0114] The vehicle completes the stabilization process within the first preset time period, and then fuel leak detection is performed using the pressure to be detected within the second preset time period.

[0115] It should be noted that the first preset duration can be 1 second, 3 seconds, 10 seconds, etc., and the second preset duration can be 7 seconds, 30 seconds, 100 seconds, etc. This application embodiment does not limit the first preset duration and the second preset duration, and can be determined according to the actual situation.

[0116] S304: Perform leak detection on the fuel evaporation system based on all pressures to be tested.

[0117] In this step, after the ECU obtains the pressure to be tested, it performs leak detection on the fuel evaporation system based on all the pressures to be tested.

[0118] In one implementation, the pressure difference between the maximum and minimum values ​​among all the pressures to be detected is calculated.

[0119] If the pressure difference is greater than the preset pressure difference threshold, it is determined that there is a leak in the fuel evaporation system.

[0120] If the pressure difference is less than or equal to the preset pressure difference threshold, it is determined that there is no leak in the fuel evaporation system.

[0121] It should be noted that the preset pressure difference threshold can be 0.5 kPa, 1 kPa, 1.5 kPa, etc. This application embodiment does not limit the preset pressure difference threshold, and it can be determined according to the actual situation.

[0122] In another implementation, a pressure change function is generated based on all the pressures to be detected. Since the first pressure sensor collects data at a fixed frequency, the time interval between the collection of each two adjacent pressures to be detected is determined, and thus the pressure change function can be generated based on all the pressures to be detected.

[0123] The integral value to be detected is obtained by integrating the pressure change function.

[0124] If the integral value to be detected is greater than the preset integral threshold, it is determined that there is a leak in the fuel evaporation system.

[0125] If the integral value to be detected is less than or equal to the preset integral threshold, it is determined that there is no leak in the fuel evaporation system.

[0126] It should be noted that the preset integration threshold can be 270, 300, 350, etc. This application embodiment does not limit the preset integration threshold, and it can be determined according to the actual situation.

[0127] For example, Figure 4 A schematic diagram of the pressure change function provided in this application is shown below. Figure 4 As shown in the figure, the thicker solid line is the curve of the pressure change function, which is the function under the condition of leakage in the fuel evaporation system. The area below the dashed line to the horizontal axis is the preset integration threshold, and the area below the curve to the horizontal axis is the integral value to be detected. The integral value to be detected is less than the preset integration threshold.

[0128] The vehicle fuel leak detection system provided in this embodiment includes a fuel tank shut-off valve, a first pressure sensor, a carbon canister desorption valve, a carbon canister shut-off valve, a gas source, and an ECU. The gas source includes a gas source shut-off valve and a gas canister. The fuel tank shut-off valve is installed in the connection pipeline between the fuel tank and the carbon canister. The carbon canister desorption valve is installed in the connection pipeline between the carbon canister and the engine. The carbon canister shut-off valve is installed in the carbon canister's ventilation pipe. The first pressure sensor is installed in the fuel evaporation system. The gas canister's outlet is connected to the fuel evaporation system through the gas source shut-off valve and pipeline. The ECU is electrically connected to the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve. The ECU is used to detect leaks in the fuel evaporation system by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve. This solution improves detection efficiency by constructing a vehicle fuel leak detection system and using the ECU to detect leaks in the fuel evaporation system, eliminating the need for manual inspection.

[0129] The following describes, through Embodiment 2 of the vehicle fuel leak detection system provided in this application, the depressurization of the fuel evaporation system before the ECU is charged.

[0130] To prevent excessive pressure inside the fuel evaporation system from preventing the subsequent gas canister from charging the system and affecting the accuracy of fuel leak detection, the ECU, upon detecting preset leak detection conditions, first controls the fuel tank shut-off valve to open, the carbon canister desorption valve to close, the carbon canister shut-off valve to open, and the gas source shut-off valve to close, thereby releasing pressure. Simultaneously, the first pressure sensor monitors the pressure release pressure.

[0131] Then, when the pressure relief reaches the atmospheric pressure at the current position of the vehicle, the system controls the opening of the fuel tank shut-off valve, the closing of the carbon canister desorption valve, the closing of the carbon canister shut-off valve, and the opening of the air source shut-off valve, and monitors the real-time pressure through the first pressure sensor.

[0132] The vehicle fuel leak detection system provided in this embodiment improves the accuracy of subsequent fuel leak detection by depressurizing the fuel evaporation system before charging the ECU's sealed fuel evaporation system.

[0133] The following describes, through Embodiment 3 of the vehicle fuel leak detection system provided in this application, the process of depressurizing the fuel evaporation system and restoring it to its pre-detection state after the ECU completes fuel leak detection.

[0134] For example, Figure 5 Schematic diagram of the process for fuel leak detection of the ECU provided in this application Figure 2 ,like Figure 5 As shown, the ECU can depressurize the fuel evaporation system and restore it to its pre-detection state through the following steps:

[0135] S501: Controls the opening of the oil tank shut-off valve, controls the closing of the carbon canister desorption valve, controls the opening of the carbon canister shut-off valve, controls the closing of the air source shut-off valve, and monitors the pressure relief pressure through the first pressure sensor.

[0136] In this step, after the ECU completes the fuel leak detection, in order to enable the vehicle to be used normally, it is necessary to first control the fuel tank shut-off valve to open, control the carbon canister desorption valve to close, control the carbon canister shut-off valve to open, and control the air source shut-off valve to close, so as to depressurize the fuel evaporation system and prevent high pressure from damaging vehicle components. At the same time, the depressurization pressure is monitored by the first pressure sensor.

[0137] S502: When the pressure relief reaches the atmospheric pressure at the current vehicle position, control the fuel tank shut-off valve to close.

[0138] In this step, when the ECU detects that the pressure relief has reached the atmospheric pressure at the current location of the vehicle, it controls the fuel tank shut-off valve to close, so that the fuel evaporation system returns to the state before the test, and the vehicle can be used normally.

[0139] It should be noted that when the control oil tank shut-off valve is closed, the states of the air source shut-off valve, carbon canister desorption valve, and carbon canister shut-off valve should remain unchanged.

[0140] The vehicle fuel leak detection system provided in this embodiment ensures that the vehicle can be used normally after a fuel leak is detected by depressurizing the fuel evaporation system and restoring it to its pre-detection state.

[0141] The following description, using Embodiment 4 of the vehicle fuel leak detection system provided in this application, illustrates a scenario where the air source in the vehicle fuel leak detection system also includes an air pump, a one-way valve, and a second pressure sensor.

[0142] For example, in Figure 2 On this basis, Figure 6 Schematic diagram of the vehicle fuel leak detection system provided in this application Figure 2 .like Figure 6 As shown, the air source 205 also includes an air pump 212, a one-way valve 213, and a second pressure sensor 214.

[0143] The outlet of the air pump 212 is connected to the inlet of the one-way valve 213 through a pipeline. The outlet of the one-way valve 213 is connected to the inlet of the air tank 208. The second pressure sensor 213 is installed in the air tank 208.

[0144] The air pump 212 and the second pressure sensor 213 are electrically connected to the ECU 206.

[0145] ECU206 is also used for:

[0146] When the second pressure sensor 213 detects that the pressure in the air tank is less than the preset inflation pressure threshold, it controls the air pump 212 to work.

[0147] When the second pressure sensor 213 detects that the pressure in the gas tank has reached the preset inflation pressure threshold, it controls the air pump 212 to stop working.

[0148] It should be noted that the preset inflation pressure threshold is greater than the preset target pressure so that the gas tank can fill the fuel evaporation system to the preset target pressure. The preset inflation pressure threshold can be 450 kPa, 500 kPa, 550 kPa, etc. This application embodiment does not limit the preset inflation pressure threshold, and it can be determined according to the actual situation.

[0149] Since the preset inflation pressure threshold is greater than the preset target pressure, rapid inflation of the fuel evaporation system can be achieved, improving the efficiency of fuel leak detection.

[0150] It should be noted that the air pump can be a compressor. The air source can be an existing component in the vehicle; vehicles with air suspension have an air source.

[0151] It should be noted that the air source may also include a dryer; the dryer is installed in the connecting pipeline between the air pump outlet and the one-way valve inlet to ensure that the gas in the gas canister is dry, to avoid corrosion of the fuel evaporation system, to avoid performance degradation of the activated carbon in the carbon canister due to adsorption of moisture, and to avoid dilution of the fuel by moisture.

[0152] The vehicle fuel leak detection system provided in this embodiment uses an air source, including an air pump, a one-way valve, and a second pressure sensor, to replenish the air tank in a timely manner, ensuring the normal operation of fuel leak detection.

[0153] The following example of the vehicle fuel leak detection method provided in this application illustrates how the ECU in the vehicle fuel leak detection system detects leaks in the fuel evaporation system.

[0154] The ECU detects leaks in the fuel evaporation system by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve.

[0155] The ECU is used to execute the technical solution of the ECU in any of the foregoing embodiments. Its implementation principle and technical effect are similar, and will not be described again here.

[0156] Figure 7 This is a schematic diagram of the structure of an ECU provided in this application. Figure 7 As shown, the ECU 70 includes:

[0157] Processor 71, memory 72, and communication interface 73;

[0158] The memory 72 is used to store the executable instructions of the processor 71;

[0159] The processor 71 is configured to execute the technical solution of the ECU in any of the foregoing embodiments by executing the executable instructions.

[0160] Optionally, the memory 72 can be either standalone or integrated with the processor 71.

[0161] Optionally, when the memory 72 is a device independent of the processor 71, the ECU 70 may further include:

[0162] Bus 74, memory 72 and communication interface 73 are connected to processor 71 through bus 74 and complete communication with each other. Communication interface 73 is used to communicate with other devices.

[0163] Optionally, the communication interface 73 can be implemented using a transceiver. The communication interface is used to enable communication between the database access device and other devices (e.g., clients, read-write databases, and read-only databases). The memory may include random access memory (RAM) and may also include non-volatile memory, such as at least one disk drive.

[0164] Bus 74 can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, only one thick line is used in the diagram, but this does not indicate that there is only one bus or one type of bus.

[0165] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0166] The ECU is used to execute the technical solution of the ECU in any of the foregoing embodiments. Its implementation principle and technical effect are similar, and will not be described again here.

[0167] This application embodiment also provides a vehicle, including the vehicle fuel leak detection system in any of the above-described vehicle fuel leak detection system embodiments;

[0168] In the vehicle fuel leak detection system of this application embodiment, the ECU is used to execute the technical solution of the ECU in any of the foregoing embodiments. Its implementation principle and technical effect are similar, and will not be repeated here.

[0169] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A vehicle fuel leak detection system, characterized in that, include: Fuel tank shut-off valve, first pressure sensor, carbon canister desorption valve, carbon canister shut-off valve, air source and electronic control unit (ECU); The gas source includes a gas source shut-off valve and a gas cylinder; The fuel tank shut-off valve is installed in the connecting pipeline between the fuel tank and the carbon canister, the carbon canister desorption valve is installed in the connecting pipeline between the carbon canister and the engine, the carbon canister shut-off valve is installed in the ventilation pipe of the carbon canister, the first pressure sensor is installed in the fuel evaporation system, and the gas outlet of the gas canister is connected to the fuel evaporation system through the gas source shut-off valve and the pipeline. The ECU is electrically connected to the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve, respectively. The ECU is used to detect leaks in the fuel evaporation system by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve.

2. The vehicle fuel leak detection system according to claim 1, characterized in that, When the ECU is used to detect leaks in the fuel evaporation system by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve, it is specifically used for: When the preset leak detection conditions are detected, the system controls the oil tank shut-off valve to open, controls the carbon canister desorption valve to close, controls the carbon canister shut-off valve to close, controls the gas source shut-off valve to open, and monitors the real-time pressure through the first pressure sensor. When the real-time pressure is detected to reach the preset target pressure, the gas source shut-off valve is controlled to close. Within a second preset time period following a first preset time period, the pressure to be detected is acquired through the first pressure sensor; Leak detection is performed on the fuel evaporation system based on all the pressures to be tested.

3. The vehicle fuel leak detection system according to claim 2, characterized in that, When the ECU is used to perform leak detection on the fuel evaporation system based on all the pressures to be detected, it is specifically used for: Generate a pressure change function based on all the pressures to be detected; The integral value to be detected is obtained by performing an integral calculation based on the pressure change function; If the integral value to be detected is greater than the preset integral threshold, it is determined that a leak has occurred in the fuel evaporation system; If the integral value to be detected is less than or equal to the preset integral threshold, it is determined that there is no leak in the fuel evaporation system.

4. The vehicle fuel leak detection system according to any one of claims 1 to 3, characterized in that, The gas source also includes an air pump, a one-way valve, and a second pressure sensor; The air outlet of the air pump is connected to the air inlet of the one-way valve through a pipeline, the air outlet of the one-way valve is connected to the air inlet of the air tank, and the second pressure sensor is installed in the air tank. The air pump and the second pressure sensor are electrically connected to the ECU; The ECU is also used for: When the second pressure sensor detects that the pressure in the air tank is lower than the preset inflation pressure threshold, the air pump is controlled to operate. When the second pressure sensor detects that the pressure in the gas tank has reached the preset inflation pressure threshold, the air pump is controlled to stop working.

5. The vehicle fuel leak detection system according to claim 4, characterized in that, The gas source also includes a dryer; The dryer is installed in the connecting pipe between the air outlet of the air pump and the air inlet of the one-way valve.

6. A method for detecting vehicle fuel leaks, characterized in that, The ECU applied in the vehicle fuel leak detection system according to any one of claims 1 to 5, the vehicle fuel leak detection method comprising: Leakage detection of the fuel evaporation system is performed by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve.

7. The vehicle fuel leak detection method according to claim 6, characterized in that, The method of detecting leaks in the fuel evaporation system by controlling the fuel tank shut-off valve, the first pressure sensor, the carbon canister desorption valve, the carbon canister shut-off valve, and the gas source shut-off valve includes: When the preset leak detection conditions are detected, the system controls the oil tank shut-off valve to open, controls the carbon canister desorption valve to close, controls the carbon canister shut-off valve to close, controls the gas source shut-off valve to open, and monitors the real-time pressure through the first pressure sensor. When the real-time pressure is detected to reach the preset target pressure, the gas source shut-off valve is controlled to close. Within a second preset time period following a first preset time period, the pressure to be detected is acquired through the first pressure sensor; Leak detection is performed on the fuel evaporation system based on all the pressures to be tested.

8. The vehicle fuel leak detection method according to claim 7, characterized in that, The step of performing leak detection on the fuel evaporation system based on all pressures to be detected includes: Calculate the pressure difference between the maximum and minimum values ​​among all the pressures to be detected; If the pressure difference is greater than a preset pressure difference threshold, it is determined that a leak has occurred in the fuel evaporation system; If the pressure difference is less than or equal to the preset pressure difference threshold, it is determined that there is no leak in the fuel evaporation system.

9. The vehicle fuel leak detection method according to claim 7, characterized in that, The step of performing leak detection on the fuel evaporation system based on all pressures to be detected includes: Generate a pressure change function based on all the pressures to be detected; The integral value to be detected is obtained by performing an integral calculation based on the pressure change function; If the integral value to be detected is greater than the preset integral threshold, it is determined that a leak has occurred in the fuel evaporation system; If the integral value to be detected is less than or equal to the preset integral threshold, it is determined that there is no leak in the fuel evaporation system.

10. The vehicle fuel leak detection method according to any one of claims 7 to 9, characterized in that, The preset leakage detection conditions include: The vehicle is powered off, the engine's cumulative operating time is greater than or equal to the preset operating time threshold, the current ambient temperature is within the preset ambient temperature range, the current fuel tank level is within the preset height range, and the atmospheric pressure at the vehicle's location is less than the preset pressure threshold.

11. The vehicle fuel leak detection method according to any one of claims 7 to 9, characterized in that, The control of opening the gas source shut-off valve includes: The gas source shut-off valve is controlled to open according to the preset opening frequency and preset single opening duration.

12. The vehicle fuel leak detection method according to any one of claims 7 to 9, characterized in that, Before controlling the opening of the fuel tank shut-off valve, controlling the closing of the carbon canister desorption valve, controlling the closing of the carbon canister shut-off valve, controlling the opening of the gas source shut-off valve, and monitoring the real-time pressure through the first pressure sensor, the vehicle fuel leak detection method further includes: The system controls the opening of the oil tank shut-off valve, the closing of the carbon canister desorption valve, the opening of the carbon canister shut-off valve, and the closing of the gas source shut-off valve, and monitors the pressure relief pressure using the first pressure sensor. The control of opening the oil tank shut-off valve, closing the carbon canister desorption valve, closing the carbon canister shut-off valve, opening the gas source shut-off valve, and monitoring real-time pressure via the first pressure sensor includes: When the pressure relief reaches the atmospheric pressure at the vehicle's current location, the system controls the opening of the fuel tank shut-off valve, the closing of the carbon canister desorption valve, the closing of the carbon canister shut-off valve, and the opening of the air source shut-off valve, and monitors the real-time pressure through the first pressure sensor.

13. The vehicle fuel leak detection method according to any one of claims 6 to 9, characterized in that, The vehicle fuel leak detection method also includes: The system controls the opening of the oil tank shut-off valve, the closing of the carbon canister desorption valve, the opening of the carbon canister shut-off valve, and the closing of the gas source shut-off valve, and monitors the pressure relief pressure using the first pressure sensor. When the pressure relief reaches the atmospheric pressure at the vehicle's current location, the fuel tank shut-off valve is closed.

14. A vehicle, characterized in that, Includes the vehicle fuel leak detection system as described in any one of claims 1 to 5; The ECU in the vehicle fuel leak detection system is used to execute the vehicle fuel leak detection method according to any one of claims 6 to 13.

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