Oil tank leakage detection system and oil tank leakage detection method

Abstract

The invention relates to an oil tank leakage detection system and an oil tank leakage detection method. The oil tank leakage detection system comprises a main pipeline, a pressurization pipeline, a high-pressure desorption pipeline, an engine and a control assembly. The control assembly is used for obtaining first air pressure of an air inlet manifold of the engine, and if the first air pressure meets a first preset requirement, the main pipeline and the pressurizing pipeline are controlled to be opened, and the high-pressure desorption pipeline is controlled to be closed, so that high-pressure gas in the air inlet manifold is guided into an oil tank; second air pressure in the oil tank is obtained, if the second air pressure meets a second preset requirement, the pressurization pipeline is controlled to be closed, and multiple third air pressures in the oil tank in the preset time period are obtained; and performing oil tank leakage detection on the oil tank according to the plurality of third air pressures. Oil tank leakage detection is carried out through the high-pressure gas in the intake manifold of the engine, detection can be automatically completed in the vehicle running process, the detection operation complexity is simplified, and the detection hardware cost is further saved.

Description

Technical Field

[0001] The present application relates to the technical field of new energy vehicles, and in particular to a fuel tank leakage detection system and a fuel tank leakage detection method. Background Art

[0002] To protect the atmospheric environment, China has enacted regulations on evaporative pollutant emissions from vehicles. For example, light-duty vehicles equipped with spark-ignition engines are required to control evaporative pollutant leaks. During use, the integrity of the gasoline tank, carbon canister, and connecting pipes must be monitored to prevent gasoline vapor from leaking into the atmosphere. Regulations for on-board diagnostic systems (OBD) also specify diagnostic rates for fuel evaporative pollutant leaks.

[0003] In current related technologies, it is usually necessary to close the valves of the various components of the fuel evaporation system corresponding to the fuel tank after the vehicle is stopped and the power is turned off, forming a closed space around the fuel tank. Then, an air pump is used to inflate the closed space to create high pressure, and the air pump current during inflation is obtained. Then, the reference air pump current required by regulations is obtained. Based on the air pump current during inflation and the reference air pump current, it can be determined whether the fuel tank is leaking. However, related technologies require the use of an air pump to inflate the closed space, which makes the detection operation complicated and the detection hardware costly. Summary of the Invention

[0004] Based on this, it is necessary to provide a fuel tank leakage detection system and a fuel tank leakage detection method to address the above technical problems.

[0005] In the first aspect, the present application provides a fuel tank leakage detection system, which includes: a main pipeline, a pressurized pipeline, a high-pressure desorption pipeline, an engine and a control component; the first end of the main pipeline is connected to the fuel tank; the second end of the main pipeline is connected to the first end of the pressurized pipeline and the first end of the high-pressure desorption pipeline respectively; the second end of the pressurized pipeline is connected to the intake manifold of the engine; the second end of the high-pressure desorption pipeline is connected to the intake manifold of the engine; the control component is connected to the main pipeline, the pressurized pipeline and the high-pressure desorption pipeline respectively, for controlling The main pipeline, the pressurized pipeline and the high-pressure desorption pipeline are opened or closed; the control component is used to obtain the first air pressure of the engine's intake manifold. If the first air pressure meets the first preset requirement, the main pipeline and the pressurized pipeline are controlled to open, and the high-pressure desorption pipeline is controlled to close, so as to introduce the high-pressure gas in the intake manifold into the fuel tank; obtain the second air pressure in the fuel tank, if the second air pressure meets the second preset requirement, control the pressurized pipeline to close, and obtain multiple third air pressures in the fuel tank within a preset time period; perform fuel tank leakage detection on the fuel tank according to the multiple third air pressures.

[0006] In one embodiment, a fuel tank isolation valve is provided on the main pipeline; a first solenoid valve is provided on the pressurized pipeline; a Venturi tube, a second solenoid valve, a carbon canister and a third solenoid valve are provided in sequence on the high-pressure desorption pipeline from the engine to the fuel tank; the fuel tank isolation valve, the first solenoid valve, the second solenoid valve and the third solenoid valve are respectively connected to the control component.

[0007] In one embodiment, the control component is further used to determine a pressure drop parameter in the oil tank within a preset time period based on the multiple third air pressures. If the pressure drop parameter is greater than a preset drop threshold, the oil tank leaks.

[0008] In a second aspect, the present application also provides a fuel tank leakage detection method, which is applied to the control component described in any one of the first aspects, and the method includes: obtaining a first air pressure of the engine intake manifold, and if the first air pressure meets a first preset requirement, controlling the main pipeline and the pressurized pipeline to open, and controlling the high-pressure desorption pipeline to close, so as to introduce the high-pressure gas in the intake manifold into the fuel tank; obtaining a second air pressure in the fuel tank, and if the second air pressure meets a second preset requirement, controlling the pressurized pipeline to close, and obtaining multiple third air pressures in the fuel tank during a preset time period; and performing fuel tank leakage detection on the fuel tank according to the multiple third air pressures.

[0009] In one embodiment, before obtaining the first air pressure of the intake manifold of the engine, the method further includes: controlling the fuel tank isolation valve of the main pipeline to close, controlling the first solenoid valve of the pressurized pipeline to close, and controlling the second solenoid valve and the third solenoid valve of the high-pressure desorption pipeline to open, so as to desorb the carbon canister through the high-pressure gas in the intake manifold of the engine.

[0010] In one embodiment, a first air pressure of the engine's intake manifold and a fuel tank level of the fuel tank are obtained; if the first air pressure meets a first preset requirement and the fuel tank level meets a third preset requirement, the fuel tank isolation valve of the main pipeline is controlled to open, the first solenoid valve of the pressurizing pipeline is controlled to open, and the second solenoid valve and the third solenoid valve of the high-pressure desorption pipeline are controlled to close, so as to introduce the high-pressure gas in the intake manifold into the fuel tank.

[0011] In one embodiment, the obtaining of the second air pressure in the fuel tank, if the second air pressure meets the second preset requirement, controlling the pressurization line to close, and obtaining multiple third air pressures in the fuel tank within a preset time period include: starting a timer after controlling the tank isolation valve of the main line to open, controlling the first solenoid valve of the pressurization line to open, and controlling the second solenoid valve and the third solenoid valve of the high-pressure desorption line to close; obtaining the second air pressure in the fuel tank in real time; based on the timer, if the second air pressure meets the second preset requirement within the preset time, controlling the first solenoid valve of the pressurization line to close, and obtaining multiple third air pressures in the fuel tank within a preset time period.

[0012] In one embodiment, the fourth air pressure of the engine intake manifold is obtained in real time; if the fourth air pressure is less than the air pressure threshold or the second air pressure does not meet the second preset requirement within the preset time, the fuel tank isolation valve of the main pipeline is controlled to be closed, the first solenoid valve of the pressurized pipeline is controlled to be closed, and the third solenoid valve of the high-pressure desorption pipeline is controlled to be opened.

[0013] In one embodiment, before obtaining the multiple third air pressures in the fuel tank during the preset time period, the method further includes: obtaining vehicle speed information and the slip rate of each wheel; determining whether the vehicle speed is stable based on the vehicle speed information; determining whether the road surface on which the vehicle is traveling is bumpy based on the slip rate of each wheel; if the vehicle speed is stable and the road surface on which the vehicle is traveling is not bumpy, obtaining the multiple third air pressures in the fuel tank during the preset time period.

[0014] In one embodiment, determining whether the road surface on which the vehicle is traveling is bumpy based on the slip rate of each wheel includes: calculating a slip rate average based on the slip rate of each wheel; determining the slip rate deviation of each wheel based on the slip rate of each wheel and the slip rate average; if the maximum slip rate deviation is greater than a preset deviation threshold, the road surface on which the vehicle is traveling is bumpy; if the maximum slip rate deviation is less than or equal to the preset deviation threshold, the road surface on which the vehicle is traveling is not bumpy.

[0015] In one embodiment, performing fuel tank leakage detection on the fuel tank based on the multiple third air pressures includes: determining a pressure drop parameter in the fuel tank within a preset time period based on the multiple third air pressures; if the pressure drop parameter is greater than a preset drop threshold, the fuel tank leaks.

[0016] The above-mentioned fuel tank leak detection system and method include a main pipeline, a pressurization pipeline, a high-pressure desorption pipeline, an engine, and a control assembly. The first end of the main pipeline is connected to the fuel tank, and the second end of the main pipeline is connected to the first end of the pressurization pipeline and the first end of the high-pressure desorption pipeline, respectively. The second end of the pressurization pipeline is connected to the engine's intake manifold. The second end of the high-pressure desorption pipeline is connected to the engine's intake manifold. The control assembly is connected to the main pipeline, the pressurization pipeline, and the high-pressure desorption pipeline, respectively, and is used to control the opening or closing of the main pipeline, the pressurization pipeline, and the high-pressure desorption pipeline. During fuel tank leak detection, the control assembly obtains a first air pressure in the engine's intake manifold. If the first air pressure meets a first preset requirement, the main pipeline and the pressurization pipeline are opened, and the high-pressure desorption pipeline is closed, thereby directing the high-pressure gas in the intake manifold into the fuel tank. The system then acquires a second pressure within the fuel tank. If the second pressure meets a second preset requirement, the pressurization line is closed and multiple third pressures within the fuel tank are acquired over a preset time period. Based on these multiple third pressures, the fuel tank is tested for leaks. By using high-pressure gas from the engine's intake manifold to perform fuel tank leak detection, the system can automatically complete the test while the vehicle is in motion, simplifying the test operation and further reducing testing hardware costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of a fuel tank leakage detection system according to one embodiment;

[0018] Figure 2 is a schematic diagram of a fuel tank leakage detection system in another embodiment;

[0019] Figure 3 Schematic diagram of a flow chart of a fuel tank leakage detection method according to one embodiment;

[0020] Figure 4 1 is a flow chart of a third air pressure detection method according to an embodiment;

[0021] Figure 5 is a schematic diagram of a fuel tank leakage detection system in a specific embodiment;

[0022] Figure 6 FIG. 1 is a flow chart of a fuel tank leakage detection method in a specific embodiment. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0024] Domestic emission regulations impose requirements on light-duty vehicles equipped with spark-ignition engines to control evaporative pollutants. These pollutants include hydrocarbon vapors lost from the vehicle's fuel system, in addition to exhaust emissions, including fuel tank breathing losses and heat soak losses. This means that during vehicle use, the integrity of the gasoline tank, carbon canister, and connecting pipes must be monitored to prevent gasoline vapor from leaking into the atmosphere. On-Board Diagnostics (OBD) regulations also specify diagnostic rates for fuel evaporative pollutant leaks. Regarding the size of the leak aperture, the regulations require that if there are one or more leak points in the evaporative system, the leakage from these leak points must be smaller than that from a 1mm diameter hole. This means that leaks from these leak points must be promptly diagnosed when their leakage is greater than or equal to that from a 1mm diameter hole.

[0025] In the current related technologies, it is necessary to close the valves of the various components of the fuel evaporation system corresponding to the fuel tank after the vehicle stops and the entire vehicle is powered off, so as to form a closed space for the fuel tank. Then, an air pump is used to inflate the closed space to form a high pressure, and the air pump current when the air pump is inflating is obtained, and then the reference air pump current required by the regulations is obtained. Among them, the reference air pump current is the air pump current when inflating a closed space with a 1mm aperture. Based on the air pump current when the air pump is inflating and the reference air pump current, it can be determined whether the fuel tank is leaking. However, the related technologies require the use of an air pump to inflate the closed space, the detection operation is complicated, and the detection hardware cost is high.

[0026] The embodiment of the present application proposes that for a supercharged engine, when the engine is operating at idle speed, there is a large negative pressure in the intake manifold, and the enclosed space is evacuated by this negative pressure, and the negative pressure value is recorded. By comparing this negative pressure value with the standard value, it can be determined whether the fuel tank is leaking, where the standard value is the negative pressure value when air is evacuated from a enclosed space with a 1mm aperture. For a supercharged engine, in addition to the large negative pressure generated in the intake manifold when the engine is operating at idle speed, the fuel tank can be vacuumed for leak detection. When the engine's supercharger is working at high load, a large positive pressure can be generated in the intake manifold. This positive pressure can replace the air pump to inflate and pressurize the fuel tank, thereby detecting leaks in the fuel tank.

[0027] In the current automotive market, with hybrid vehicle batteries growing larger and motor power increasing, engines are mostly operated in high-speed parallel direct drive conditions, with engine idling almost nonexistent. Therefore, when a supercharged engine is under heavy load, the high positive pressure generated in the intake manifold is used to inflate and pressurize the fuel tank, thereby performing leak detection. This method has no impact on engine or vehicle energy consumption, and offers high detection accuracy. Furthermore, utilizing positive pressure inflation during heavy engine load has less impact on normal engine operation than negative pressure extraction during engine idling, preventing negative pressure from drawing gasoline vapor from the tank.

[0028] In one embodiment, Figure 1 As shown, a fuel tank leak detection system is provided, comprising: a main pipeline 100, a pressurized pipeline 200, a high-pressure desorption pipeline 300, an engine 400, and a control assembly 500. The first end of the main pipeline 100 is connected to the fuel tank; the second end of the main pipeline 100 is connected to the first end of the pressurized pipeline 200 and the first end of the high-pressure desorption pipeline 300, respectively. The second end of the pressurized pipeline 200 is connected to the intake manifold of the engine 400. The second end of the high-pressure desorption pipeline 300 is connected to the intake manifold of the engine 400. The control assembly 500 is connected to the main pipeline 100, the pressurized pipeline 200, and the high-pressure desorption pipeline 300, respectively, and is used to control the opening or closing of the main pipeline 100, the pressurized pipeline 200, and the high-pressure desorption pipeline 300.

[0029] Solenoid valves are respectively provided on the main pipeline 100, the pressurized pipeline 200 and the high-pressure desorption pipeline 300. The control component 500 is respectively connected to the main pipeline 100, the pressurized pipeline 200 and the high-pressure desorption pipeline 300, that is, it is respectively connected to the solenoid valves in each pipeline. By controlling the opening or closing of the solenoid valves, the purpose of controlling the opening or closing of the main pipeline 100, the pressurized pipeline 200 and the high-pressure desorption pipeline 300 is achieved.

[0030] Main line 100 connects pressurization line 200 and high-pressure desorption line 300 to the fuel tank. Pressurization line 200 opens when engine 400 meets fuel tank leak detection criteria, drawing high-pressure gas from the intake manifold into the fuel tank during high-load conditions.

[0031] A carbon canister is provided on the high-pressure desorption line 300 to adsorb fuel vapor within the fuel tank. When the fuel within the fuel tank evaporates, the fuel vapor enters the carbon canister through the high-pressure desorption line 300. The activated carbon within the carbon canister adsorbs the fuel vapor, preventing it from being directly discharged into the atmosphere. A venturi tube is provided on the high-pressure desorption line 300. When the engine 400 is operating and gas flows through the intake manifold of the engine 400, the gas velocity increases and the static pressure decreases during the contraction phase of the venturi tube, thereby forming a negative pressure within the venturi tube. This negative pressure can draw the fuel vapor adsorbed in the carbon canister into the intake manifold of the engine 400, where it mixes with air and is then sent to the combustion chamber of the engine 400 for combustion.

[0032] The engine 400 can be a supercharged engine 400. Through the supercharger turbine and supercharger impeller in the engine 400, high pressure is formed in the intake manifold of the engine 400. The high-pressure gas in the intake manifold during the high-load stage of the engine 400 is introduced into the fuel tank through the pressurized pipeline 200, forming positive pressure in the fuel tank.

[0033] The control component 500 may be an engine controller, which controls the operating parameters of the engine 400 in real time by collecting and processing data from various sensors to ensure that the engine 400 can operate efficiently and stably under different operating conditions.

[0034] When performing a fuel tank leakage test, the control component 500 is used to obtain a first air pressure of the intake manifold of the engine 400. If the first air pressure meets a first preset requirement, the main pipeline 100 and the pressurized pipeline 200 are controlled to be opened, and the high-pressure desorption pipeline 300 is controlled to be closed, so as to introduce the high-pressure gas in the intake manifold into the fuel tank; obtain a second air pressure in the fuel tank. If the second air pressure meets a second preset requirement, the pressurized pipeline 200 is controlled to be closed, and obtain multiple third air pressures in the fuel tank within a preset time period; and perform a fuel tank leakage test on the fuel tank according to the multiple third air pressures.

[0035] A first air pressure sensor is installed in the intake manifold of engine 400. The first air pressure sensor can be located between the throttle valve and the supercharger impeller of the intake manifold and is used to detect the air pressure in the intake manifold. The first air pressure sensor can be connected to the control component 500 and transmit the collected air pressure information to the control component 500. A second air pressure sensor is installed in the fuel tank and is used to detect the air pressure within the fuel tank and transmit the air pressure within the fuel tank to the control component 500.

[0036] The control component 500 obtains the first air pressure of the intake manifold of the engine 400 through the first air pressure sensor. It also determines in real time whether the first air pressure meets the first preset requirement. If it does, that is, the engine 400's high-load supercharger is working, and high pressure is formed in the intake manifold. Among them, the first preset requirement is that the first air pressure is greater than the first air pressure threshold. The first air pressure threshold needs to be greater than one standard atmospheric pressure. It can be set according to actual usage requirements. This embodiment does not specifically limit it. Preferably, the first air pressure threshold can be 1.1-1.2 standard atmospheric pressures. When the first air pressure meets the first preset requirement, that is, the first air pressure is greater than the first air pressure threshold, the main pipeline 100 and the pressurized pipeline 200 are controlled to open, and the high-pressure desorption pipeline 300 is controlled to close, so that the high-pressure gas in the intake manifold of the engine 400 is introduced into the fuel tank.

[0037] During the process of introducing high-pressure gas into the fuel tank, the second air pressure in the fuel tank is obtained in real time through the second air pressure sensor. It is also determined in real time whether the second air pressure meets the second preset requirement, wherein the second preset requirement is that the second air pressure is greater than the second air pressure threshold. The second air pressure threshold needs to be greater than one standard atmospheric pressure and less than the first air pressure threshold. It can be set according to actual usage requirements. This embodiment does not make specific limitations. Preferably, the second air pressure threshold can be 1.03-1.04 standard atmospheric pressure. When the second air pressure meets the second preset requirement, that is, the second air pressure is greater than the second air pressure threshold, the pressurized pipeline 200 is controlled to close to form a closed space in the fuel tank.

[0038] After the enclosed space is formed, the second sensor collects multiple third air pressures within the fuel tank within a preset time period. The fuel tank is then tested for leaks based on these multiple third air pressures. It will be appreciated that after the enclosed space is formed, if no leak exists, the multiple third air pressures will change slowly over time, while if a leak exists, the multiple third air pressures will change rapidly over time. Therefore, the degree of change between these multiple third air pressures can be used to determine whether a leak exists in the fuel tank.

[0039] In this embodiment, the fuel tank leak detection system includes: a main pipeline 100, a pressurized pipeline 200, a high-pressure desorption pipeline 300, an engine 400, and a control component 500. The first end of the main pipeline 100 is connected to the fuel tank, and the second end of the main pipeline 100 is connected to the first end of the pressurized pipeline 200 and the first end of the high-pressure desorption pipeline 300. The second end of the pressurized pipeline 200 is connected to the intake manifold of the engine 400. The second end of the high-pressure desorption pipeline 300 is connected to the intake manifold of the engine 400. The control component 500 is connected to the main pipeline 100, the pressurized pipeline 200, and the high-pressure desorption pipeline 300, respectively, and is used to control the opening or closing of the main pipeline 100, the pressurized pipeline 200, and the high-pressure desorption pipeline 300. When performing a fuel tank leak test, control component 500 obtains a first air pressure from the intake manifold of engine 400. If the first air pressure meets a first preset requirement, control component 500 controls the main line 100 and pressurized line 200 to open and the high-pressure desorption line 300 to close, thereby directing the high-pressure gas in the intake manifold into the fuel tank. It then obtains a second air pressure from the fuel tank. If the second air pressure meets a second preset requirement, control component 500 controls the pressurized line 200 to close, and obtains multiple third air pressures from the fuel tank during a preset time period. The fuel tank is then tested for fuel tank leaks based on these multiple third air pressures. By using the high-pressure gas in the intake manifold of engine 400 to perform fuel tank leak testing, the test can be completed automatically while the vehicle is in motion, simplifying the complexity of the test operation and further reducing the cost of the test hardware.

[0040] In one embodiment, Figure 2 As shown, a specific fuel tank leakage detection system is provided, in which a fuel tank isolation valve 110 is provided on the main pipeline 100; a first solenoid valve 210 is provided on the pressurized pipeline 200; a venturi tube 310, a second solenoid valve 320, a carbon canister 330 and a third solenoid valve 340 are provided in sequence on the high-pressure desorption pipeline 300 from the engine 400 to the fuel tank; the fuel tank isolation valve 110, the first solenoid valve 210, the second solenoid valve 320 and the third solenoid valve 340 are respectively connected to the control component 500.

[0041] Fuel tank isolation valve 110, also known as Fuel Tank Isolation Valve (FTIV), regulates fuel tank pressure, preventing excessive pressure due to fuel vapor accumulation and ensuring that the pressure within the tank remains within a safe range. During refueling, FTIV 110 opens to ensure a smooth refueling process and prevent the nozzle from tripping. When engine 400 is stopped, FTIV 110 closes to prevent fuel vapor from escaping the tank and into the atmosphere. When engine 400 is running, FTIV 110 opens, allowing fuel vapor to enter canister 330, where it is then drawn into and combusted by engine 400.

[0042] The first solenoid valve 210 controls the opening and closing of the pressurization line 200. When the first solenoid valve 210 and the fuel tank isolation valve 110 are open, the high-pressure gas in the engine 400 intake manifold is introduced into the fuel tank. When fuel tank leak detection is not required, the first solenoid valve 210 is normally closed. The second solenoid valve 320 and the third solenoid valve 340 control the opening and closing of the high-pressure desorption line 300. The third solenoid valve 340 is closed during fuel tank leak detection, creating a sealed space within the fuel tank. During this process, when the high-pressure gas in the engine 400 intake manifold is introduced into the fuel tank, a high pressure is generated within the tank. When fuel tank leak detection is not required, the third solenoid valve 340 is normally open. The second solenoid valve 320 controls the desorption of the carbon canister 330. When the second solenoid valve 320 is open, it draws fuel vapor from the canister 330 into the engine 400.

[0043] Carbon canister 330 is used to absorb fuel vapor generated by the fuel tank. Because the activated carbon inside carbon canister 330 has a limited capacity and cannot collect fuel vapor indefinitely, when carbon canister 330 is full, the resulting fuel vapor will escape into the atmosphere, polluting the environment and causing serious consequences such as excessive vehicle emissions. Therefore, it is necessary to open second solenoid valve 320, creating negative pressure in venturi tube 310, which draws fresh air from the outside into carbon canister 330. This desorbs the fuel vapor from the activated carbon and introduces it into the cylinders of engine 400 for combustion, thus completing the desorption process.

[0044] The control assembly 500 is connected to the fuel tank isolation valve 110 , the first solenoid valve 210 , the second solenoid valve 320 and the third solenoid valve 340 respectively, and is used to control the opening and closing of the fuel tank isolation valve 110 , the first solenoid valve 210 , the second solenoid valve 320 and the third solenoid valve 340 .

[0045] This embodiment provides solenoid valves on the main pipeline 100, the pressurized pipeline 200 and the high-pressure desorption pipeline 300 respectively, and then connects all the solenoid valves through the control component 500. By controlling the opening or closing of the solenoid valves, the main pipeline 100, the pressurized pipeline 200 and the high-pressure desorption pipeline 300 are opened or closed, thereby improving the control accuracy of the pipeline and further improving the accuracy of fuel tank leakage detection.

[0046] In one embodiment, the control component 500 is further configured to determine a pressure drop parameter in the fuel tank within a preset time period based on multiple third air pressures. If the pressure drop parameter is greater than a preset drop threshold, the fuel tank leaks.

[0047] The preset drop threshold can be set according to actual use requirements, and this embodiment does not make specific limitations. It is understandable that the preset drop threshold can also be set according to regulatory requirements. For example, regulations require that the leakage volume of all leak points must be less than the leakage volume generated by a small hole with a diameter of 1 mm. Therefore, first set up a fuel tank with a small hole of 1 mm on the fuel tank, then pressurize the fuel tank to the second air pressure threshold, and then close the fuel tank to form a closed space. During a preset time period, multiple air pressures in the fuel tank are obtained, and the preset drop threshold is determined based on the multiple air pressures. Specifically, multiple air pressures can be collected at a preset sampling period within a preset time period, and the sampling time and air pressure can be linearly fitted to obtain a pressure signal curve, and the average drop slope of the pressure signal curve can be used as the preset drop threshold. It is also possible to collect air pressure at the start time and the end time within the preset time period, and use the difference between the two air pressures as the preset drop threshold.

[0048] If the pressure drop parameter is determined based on a pressure signal curve obtained through linear fitting, then the multiple third air pressures are multiple third air pressures collected within a preset time period and at a preset sampling period. A linear fit is performed on the multiple third air pressures and the corresponding sampling times to obtain an actual pressure signal curve. The actual average downward slope of the actual pressure signal curve is calculated and used as the pressure drop parameter. When the pressure drop parameter is greater than a preset drop threshold, it indicates that the leakage rate is greater than the leakage rate corresponding to a small hole with a diameter of 1 mm, indicating that the fuel tank is leaking. When the pressure drop parameter is less than or equal to the preset drop threshold, it indicates that regulatory requirements are met and the fuel tank is not leaking.

[0049] If the pressure drop parameter is determined based on the difference in air pressures collected between the start and end times, then the multiple third air pressures are the two third air pressures corresponding to the actual start and end times of the preset time period. The actual difference between the two third air pressures is calculated and used as the pressure drop parameter. When the pressure drop parameter is greater than the preset drop threshold, it indicates that the leakage rate is greater than the leakage rate corresponding to a small hole with a diameter of 1 mm, indicating that the fuel tank is leaking. When the pressure drop parameter is less than or equal to the preset drop threshold, it indicates that the regulatory requirements are met and the fuel tank is not leaking.

[0050] In this embodiment, after the pressurized line is closed, the fuel tank forms a sealed space. During this time, multiple third air pressures within the fuel tank are acquired within a preset time period. Based on these third air pressures, a pressure drop parameter is determined. This pressure drop parameter is compared with a preset drop threshold required by regulations. If the pressure drop exceeds the preset drop threshold, a fuel tank leak is determined, thereby improving the accuracy of fuel tank leak detection.

[0051] Based on the same inventive concept, embodiments of the present application also provide a fuel tank leakage detection method for use with the aforementioned fuel tank leakage detection system. The solution provided by this method is similar to the solution described in the aforementioned fuel tank leakage detection system. Therefore, the specific limitations in one or more of the following fuel tank leakage detection method embodiments can be found in the aforementioned limitations on the fuel tank leakage detection system and will not be further elaborated here.

[0052] In one embodiment, Figure 3 As shown, a fuel tank leakage detection method is provided, comprising the following steps:

[0053] Step 301, obtaining a first air pressure of the engine intake manifold. If the first air pressure meets a first preset requirement, the main pipeline and the pressurized pipeline are controlled to be opened, and the high-pressure desorption pipeline is controlled to be closed to guide the high-pressure gas in the intake manifold into the fuel tank.

[0054] The control component obtains the first air pressure of the engine's intake manifold through the first air pressure sensor. And determines in real time whether the first air pressure meets the first preset requirement. If it meets the first preset requirement, that is, the engine's high-load supercharger is working, high pressure is formed in the intake manifold. Among them, the first preset requirement, that is, the first air pressure is greater than the first air pressure threshold, the first air pressure threshold needs to be greater than one standard atmospheric pressure, and can be set according to actual use requirements. This embodiment does not make specific limitations. Preferably, the first air pressure threshold can be 1.1-1.2 standard atmospheric pressures. When the first air pressure meets the first preset requirement, that is, the first air pressure is greater than the first air pressure threshold, the main pipeline and the pressurized pipeline are controlled to open, and the high-pressure desorption pipeline is controlled to close, so as to guide the high-pressure gas in the engine's intake manifold into the fuel tank.

[0055] Step 302: Obtain a second air pressure in the fuel tank. If the second air pressure meets a second preset requirement, control the pressurization pipeline to close, and obtain multiple third air pressures in the fuel tank within a preset time period.

[0056] During the process of introducing high-pressure gas into the fuel tank, the second air pressure in the fuel tank is obtained in real time through the second air pressure sensor. And it is determined in real time whether the second air pressure meets the second preset requirement, wherein the second preset requirement is that the second air pressure is greater than the second air pressure threshold. The second air pressure threshold needs to be greater than one standard atmospheric pressure and less than the first air pressure threshold. It can be set according to actual use requirements. This embodiment does not make specific limitations. Preferably, the second air pressure threshold can be 1.03-1.04 standard atmospheric pressure. When the second air pressure meets the second preset requirement, that is, the second air pressure is greater than the second air pressure threshold, the pressurized pipeline is controlled to close to form a closed space in the fuel tank.

[0057] Step 303: Perform a fuel tank leakage detection on the fuel tank according to the multiple third air pressures.

[0058] After the enclosed space is formed, the second sensor collects multiple third air pressures within the fuel tank within a preset time period. The fuel tank is then tested for leaks based on these multiple third air pressures. It will be appreciated that after the enclosed space is formed, if no leak exists, the multiple third air pressures will change slowly over time, while if a leak exists, the multiple third air pressures will change rapidly over time. Therefore, the degree of change between these multiple third air pressures can be used to determine whether a leak exists in the fuel tank.

[0059] This embodiment uses high-pressure gas in the engine's intake manifold to detect fuel tank leaks. The detection can be automatically completed while the vehicle is driving, which simplifies the complexity of the detection operation and further saves the detection hardware cost.

[0060] In one embodiment, before obtaining the first air pressure of the engine's intake manifold, that is, before performing a fuel tank leak test on the fuel tank, a carbon canister desorption process is required. Specifically, the fuel tank isolation valve of the main pipeline is closed, the first solenoid valve of the pressurization pipeline is closed, and the second and third solenoid valves of the high-pressure desorption pipeline are opened, so that the carbon canister can be desorbed using the high-pressure gas in the engine's intake manifold.

[0061] When desorbing the carbon canister, it is necessary to control the fuel tank isolation valve of the main pipeline to be closed to close the main pipeline. Control the first solenoid valve of the pressurized pipeline to be closed to close the pressurized pipeline. Control the second solenoid valve and the third solenoid valve of the high-pressure desorption pipeline to be opened. At this time, gas flows through the engine intake manifold, and the gas forms a negative pressure in the venturi tube. This negative pressure can suck the fuel vapor adsorbed in the carbon canister into the engine intake manifold, where it is mixed with air and sent to the engine combustion chamber for combustion, thus completing the desorption process of the carbon canister.

[0062] In this embodiment, before performing the fuel tank leakage detection, the carbon canister is first subjected to a desorption process, thereby preventing the fuel in the fuel tank from volatilizing into the atmosphere during the fuel tank leakage detection.

[0063] In one embodiment, while determining whether the first air pressure meets the first preset requirement, it is also necessary to determine whether the fuel tank level meets the third preset requirement. Specifically, the first air pressure of the engine intake manifold and the fuel tank level are obtained; if the first air pressure meets the first preset requirement and the fuel tank level meets the third preset requirement, the fuel tank isolation valve of the main pipeline is controlled to open, the first solenoid valve of the pressurization pipeline is controlled to open, and the second and third solenoid valves of the high-pressure desorption pipeline are controlled to close, so as to guide the high-pressure gas in the intake manifold into the fuel tank.

[0064] The control assembly obtains a first air pressure in the engine's intake manifold via a first air pressure sensor. A liquid level sensor is also provided within the fuel tank and connected to the control assembly. The control assembly obtains the fuel tank liquid level via the liquid level sensor. The third preset condition is that the fuel tank liquid level is within a preset fuel tank liquid level range. This preset fuel tank liquid level range can be set based on actual usage requirements and is not specifically limited in this embodiment. Properly setting the preset fuel tank liquid level range can further improve the accuracy of fuel tank leak detection. When the first air pressure meets the first preset requirement (i.e., the first air pressure is greater than the first air pressure threshold), and the fuel tank liquid level meets the third preset requirement (i.e., the fuel tank liquid level is within the preset fuel tank liquid level range), both the engine and the fuel tank meet the fuel tank leak detection conditions. The fuel tank isolation valve in the main line is controlled to open, the first solenoid valve in the pressurization line is controlled to open, and the second and third solenoid valves in the high-pressure desorption line are controlled to close, thereby directing high-pressure gas from the intake manifold into the fuel tank. If the first air pressure does not meet the first preset requirement (i.e., the first air pressure is less than or equal to the first air pressure threshold), or the fuel tank level does not meet the third preset requirement (i.e., the fuel tank level is not within the preset fuel tank level range), or both the first air pressure and the fuel tank level do not meet the third preset requirement, the solenoid valves in the pipeline are not controlled. In this case, the fuel tank isolation valve opens, the first solenoid valve closes, the third solenoid valve opens, and the second solenoid valve opens when canister desorption is required.

[0065] By setting the first preset condition and the third preset condition, it is determined whether the engine and the fuel tank meet the detection conditions, thereby further improving the accuracy of fuel tank leakage detection.

[0066] In one embodiment, obtaining a second air pressure in the fuel tank, controlling the pressurization pipeline to close if the second air pressure meets a second preset requirement, and obtaining multiple third air pressures in the fuel tank during a preset time period specifically include the following steps:

[0067] Step 1: After the tank isolation valve of the main pipeline is opened, the first solenoid valve of the pressurized pipeline is opened, and the second and third solenoid valves of the high-pressure desorption pipeline are closed, the timer starts timing.

[0068] When both the engine and the fuel tank meet the fuel tank leak detection criteria, the fuel tank isolation valve in the main control line opens, the first solenoid valve in the pressurization line opens, and the second and third solenoid valves in the high-pressure desorption line close, directing high-pressure gas from the intake manifold into the fuel tank. The control component has a timing function. When all solenoid valves have completed control, the control component begins counting, which also starts the timer. The timer indicates how long the high-pressure gas is being directed into the fuel tank.

[0069] Step 2: Obtain the second air pressure in the fuel tank in real time.

[0070] After all the solenoid valves have completed control, the control component obtains the second air pressure in the fuel tank through the second air pressure sensor in real time.

[0071] Step 3: Based on the timer, if the second air pressure meets the second preset requirement within the preset time, the first solenoid valve of the pressurized pipeline is controlled to close, and multiple third air pressures in the oil tank within the preset time period are obtained.

[0072] The timer is obtained in real time. When the timer is less than a preset time and the second air pressure is greater than a second pressure threshold, the first solenoid valve of the pressurization line is controlled to close, and multiple third air pressures in the fuel tank are obtained for a preset time period. If the timer is less than the preset time and the second air pressure is greater than the second pressure threshold, the air pressure in the fuel tank meets the pressure conditions for fuel tank leak detection.

[0073] In one embodiment, during the process of introducing high-pressure gas into the fuel tank, a fourth air pressure in the engine's intake manifold is also acquired in real time. If the fourth air pressure is less than a pressure threshold or the second air pressure does not meet a second preset requirement within a preset time, the fuel tank isolation valve in the main pipeline is closed, the first solenoid valve in the pressurization pipeline is closed, and the third solenoid valve in the high-pressure desorption pipeline is opened. Specifically, during the process of introducing high-pressure gas into the fuel tank, if the fourth air pressure in the engine's intake manifold is less than or equal to the second pressure threshold, indicating that the air pressure in the engine is insufficient to support fuel tank leak detection, the fuel tank isolation valve in the main pipeline is closed, the first solenoid valve in the pressurization pipeline is closed, and the third solenoid valve in the high-pressure desorption pipeline is opened. If the timed interval is greater than or equal to the preset time and the second air pressure is less than or equal to the second pressure threshold, the detection condition is not met and fuel tank pressurization needs to be terminated. The fuel tank isolation valve in the main pipeline is closed, the first solenoid valve in the pressurization pipeline is closed, and the third solenoid valve in the high-pressure desorption pipeline is opened.

[0074] This embodiment monitors the fourth air pressure of the engine intake manifold in real time during the process of introducing high-pressure gas into the fuel tank, thereby preventing the pressure in the intake manifold from being too low, which could cause fuel vapor to flow back into the pressurization line. Furthermore, if the timer duration is greater than or equal to the preset time, and the second air pressure is less than or equal to the second air pressure threshold, it indicates that an abnormality has occurred during the fuel tank pressurization process, preventing smooth pressurization and requiring the pressurization process to be terminated.

[0075] In one embodiment, before obtaining multiple third air pressures, the vehicle needs to be tested for stability. When the vehicle is unstable, the fuel in the tank will also move, thereby affecting the detection accuracy of the third air pressure. Therefore, it is necessary to determine that the vehicle is stable before obtaining multiple third air pressures. Figure 4 As shown, a third air pressure detection method is provided, which specifically includes the following steps:

[0076] Step 401: Obtain vehicle speed information and the slip rate of each wheel.

[0077] Determining vehicle stability requires obtaining vehicle speed information and the slip ratio of each of the four wheels. The slip ratio describes the degree of slip between the wheel and the ground. Specifically, it is the ratio of the difference between the wheel speed and the vehicle speed to the vehicle speed. The slip ratio can be used to assess wheel grip and vehicle stability.

[0078] Step 402: Determine whether the vehicle speed is stable based on the vehicle speed information.

[0079] After obtaining the vehicle speed information, a determination is made based on the vehicle speed information to determine whether the vehicle speed is stable. Specifically, multiple pieces of vehicle speed information are obtained within a preset time range, and the current vehicle acceleration is determined based on the multiple pieces of vehicle speed information. If the acceleration is less than a preset acceleration threshold, the vehicle speed is stable; if the acceleration is greater than or equal to the preset acceleration threshold, the vehicle speed is unstable.

[0080] Step 403: Determine whether the road surface on which the vehicle is traveling is bumpy based on the slip rate of each wheel.

[0081] After obtaining the slip rate corresponding to each of the vehicle's four wheels, the average slip rate is first calculated based on the slip rate of each wheel. Then, based on the slip rate of each wheel and the average slip rate, the slip rate deviation of each wheel is determined. Specifically, the absolute value of the average slip rate is subtracted from the wheel's slip rate, and this is taken as the slip rate deviation of the corresponding wheel. After calculating the slip rate deviation of each wheel, the maximum value of all slip rate deviations, i.e., the maximum slip rate deviation, is determined. If the maximum slip rate deviation is greater than a preset deviation threshold, the vehicle is traveling on a bumpy road. If the maximum slip rate deviation is less than or equal to the preset deviation threshold, the vehicle is traveling on a smooth road.

[0082] Step 404 : If the vehicle speed is stable and the road surface on which the vehicle is traveling is not bumpy, a plurality of third air pressures in the fuel tank during a preset time period are obtained.

[0083] When the vehicle speed is stable and the road surface on which the vehicle is traveling is not bumpy, it means that the vehicle is stable and the detected air pressure in the fuel tank is relatively accurate. Therefore, multiple third air pressures in the fuel tank during a preset time period are obtained.

[0084] This embodiment performs a vehicle stability test before obtaining multiple third air pressures. When the vehicle is in a stable state, multiple third air pressures in the fuel tank are obtained, thereby ensuring the detection accuracy of the air pressure in the fuel tank and further improving the accuracy of fuel tank leakage detection.

[0085] In one embodiment, performing fuel tank leakage detection on the fuel tank according to the plurality of third air pressures specifically includes the following steps:

[0086] The preset drop threshold can be set according to actual use requirements, and this embodiment does not make specific limitations. It is understandable that the preset drop threshold can also be set according to regulatory requirements. For example, regulations require that the leakage volume of all leak points must be less than the leakage volume generated by a small hole with a diameter of 1 mm. Therefore, first set up a fuel tank with a small hole of 1 mm on the fuel tank, then pressurize the fuel tank to the second air pressure threshold, and then close the fuel tank to form a closed space. During a preset time period, multiple air pressures in the fuel tank are obtained, and the preset drop threshold is determined based on the multiple air pressures. Specifically, multiple air pressures can be collected at a preset sampling period within a preset time period, and the sampling time and air pressure can be linearly fitted to obtain a pressure signal curve, and the average drop slope of the pressure signal curve can be used as the preset drop threshold. It is also possible to collect air pressure at the start time and the end time within the preset time period, and use the difference between the two air pressures as the preset drop threshold.

[0087] Step 1: Determine a pressure drop parameter in the fuel tank during a preset time period based on multiple third air pressures.

[0088] If the pressure drop parameter is determined based on a pressure signal curve obtained by linear fitting, then the multiple third air pressures are multiple third air pressures collected within a preset time period and at a preset sampling period. The multiple third air pressures and the corresponding sampling times are linearly fitted to obtain an actual pressure signal curve, and the actual average downward slope of the actual pressure signal curve is calculated, and the actual average downward slope is used as the pressure drop parameter.

[0089] If the pressure drop parameter is determined based on the air pressure difference collected at the start time and the end time, the multiple third air pressures are two third air pressures corresponding to the actual start time and the actual end time of the preset time period, and the actual difference between the two third air pressures is calculated and used as the pressure drop parameter.

[0090] Step 2: If the pressure drop parameter is greater than the preset drop threshold, the fuel tank leaks.

[0091] When the pressure drop parameter is greater than the preset drop threshold, it means that the leakage rate is greater than the leakage rate corresponding to a small hole with a diameter of 1 mm, and the fuel tank is leaking at this time; when the pressure drop parameter is less than or equal to the preset drop threshold, it means that the regulatory requirements are met and the fuel tank is not leaking at this time.

[0092] This embodiment compares the pressure drop parameter with a preset drop threshold required by regulations. When the pressure drop parameter is greater than the preset drop threshold, it is determined that the fuel tank is leaking, thereby improving the accuracy of fuel tank leakage detection.

[0093] In one embodiment, after the tank leakage detection is completed, the tank isolation valve of the main pipeline is closed, the first solenoid valve of the pressurizing pipeline is closed, and the third solenoid valve of the high-pressure desorption pipeline is opened.

[0094] In one specific embodiment, Figure 5 as well as Figure 6 As shown, Figure 5 For a specific fuel tank leak detection system, Figure 6 The invention provides a specific fuel tank leakage detection method.

[0095] Compared to a normal supercharged engine, this embodiment adds a pressurization line. This line is used to introduce high-pressure gas from the intake manifold into the fuel tank to create positive pressure during high engine load conditions, when the fuel tank leak detection conditions are met. This embodiment also adds a first solenoid valve, also known as the solenoid valve for the pressurization line. When the fuel tank leak detection conditions are not met, this valve closes the connection between the intake manifold and the fuel tank. This prevents fuel vapor from entering the intake manifold when the intake manifold is under negative pressure, leading to unstable combustion and further speed fluctuations. It also prevents high-pressure air from continuously blowing fuel vapor from the fuel tank into the carbon canister when the intake manifold is under positive pressure, which prevents the carbon canister from desorbing it in time, leading to fuel vapor overflow and excessive emissions. This embodiment also adds a third solenoid valve, also known as the carbon canister shut-off valve. This valve closes the connection between the fuel tank and the outside atmosphere during the fuel tank leak detection, creating a sealed space.

[0096] Before conducting a fuel tank leak test, the carbon canister must first be desorbed and the desorption must be completed.

[0097] Then check whether the pressure of the engine intake manifold can meet the pressure requirement of the fuel tank when performing fuel tank leakage detection, and whether the liquid level of the fuel tank meets the liquid level requirement.

[0098] When the pressure of the intake manifold meets the requirements and the liquid level of the fuel tank meets the liquid level requirements, open the fuel tank isolation valve (FTIV), open the first solenoid valve, that is, the solenoid valve of the pressurized pipeline, and close the other solenoid valves of the fuel tank system that are connected to the outside world, that is, the second solenoid valve and the third solenoid valve, that is, Figure 5 The carbon canister solenoid valve and carbon canister shut-off valve are installed in the fuel tank. The high pressure in the intake manifold is then used to pressurize the fuel tank.

[0099] During the pressurization process, it is necessary to monitor the pressure changes in the intake manifold in real time to prevent the intake manifold pressure from being too low and fuel vapor from flowing back into the intake manifold. It is also necessary to monitor whether the pressure in the fuel tank reaches the second pressure threshold within the set time. If an abnormality occurs during the pressurization process, preventing the smooth pressurization process, the pressurization process must be terminated, the solenoid valve of the pressurization line must be closed, the carbon canister shut-off valve must be opened, and the fuel tank isolation valve must be closed.

[0100] After the pressurization is successfully completed, the solenoid valve of the pressurization line is closed to seal the entire fuel evaporation system and maintain high pressure.

[0101] Before determining whether a fuel tank leak exists, it's necessary to determine whether the vehicle's current operating conditions meet the test requirements. For example, it's necessary to determine whether the vehicle's speed is stable and whether the road surface is bumpy. This prevents the fuel level in the tank from fluctuating, which could cause fluctuations in the pressure signal detected by the tank's pressure sensor and affect the test results. If the vehicle's speed remains unstable or the road surface is bumpy for an extended period, the fuel tank leak test will need to be terminated.

[0102] When the vehicle speed is stable and the road surface is smooth, the system calculates the rate of decrease of the fuel tank pressure signal and compares it with a pre-stored reference value required by regulations to determine whether the current rate of decrease exceeds the reference value. If the current rate of decrease exceeds the reference value, it indicates that there is a leak in the fuel tank evaporative system that is greater than the regulatory requirement. If the current rate of decrease is less than or equal to the reference value, there is no leak in the fuel tank evaporative system that is greater than the regulatory requirement.

[0103] After completing the fuel tank leak test, it is necessary to close the solenoid valve of the pressurized line, open the carbon canister shut-off valve, and close the fuel tank isolation valve. During the subsequent engine operation, the carbon canister should be desorbed.

[0104] This embodiment of the application adds a pressurized line and a solenoid valve to the line, allowing high-pressure gas from the engine's intake manifold to be pumped into the fuel tank via the pressurized line, thereby reducing the cost of an external air pump. Furthermore, utilizing the high pressure of the supercharged engine for pumping air makes it easier to meet the diagnostic requirements for the aroma manifold negative pressure scheme without affecting engine fuel consumption. Since no additional fuel enters the cylinders for combustion during the fuel tank leak detection process, engine operating stability is improved.

[0105] It should be understood that, although the steps in the flowcharts of the above embodiments are shown in sequence as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be performed in other orders. Moreover, at least a portion of the steps in the flowcharts of the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily to be performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0106] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the above-mentioned embodiments. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), data processing logic devices based on quantum computing, and the like.

[0107] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0108] The above embodiments merely illustrate several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A fuel tank leakage detection system, characterized in that: The fuel tank leakage detection system includes: a main pipeline, a pressurized pipeline, a high-pressure desorption pipeline, an engine and a control component; The first end of the main pipeline is connected to the oil tank; the second end of the main pipeline is connected to the first end of the pressurizing pipeline and the first end of the high-pressure desorption pipeline respectively; The second end of the pressurized pipeline is in communication with the intake manifold of the engine; The second end of the high-pressure desorption pipeline is communicated with the intake manifold of the engine; The control components are respectively connected to the main pipeline, the pressurized pipeline and the high-pressure desorption pipeline, and are used to control the opening or closing of the main pipeline, the pressurized pipeline and the high-pressure desorption pipeline respectively; The control component is used to obtain a first air pressure of the engine's intake manifold. If the first air pressure meets a first preset requirement, the control component controls the main pipeline and the pressurized pipeline to open, and controls the high-pressure desorption pipeline to close, so as to introduce the high-pressure gas in the intake manifold into the fuel tank; obtain a second air pressure in the fuel tank. If the second air pressure meets a second preset requirement, the control component controls the pressurized pipeline to close, and obtains multiple third air pressures in the fuel tank within a preset time period; and performs fuel tank leakage detection on the fuel tank based on the multiple third air pressures.

2. The fuel tank leakage detection system according to claim 1, characterized in that: A fuel tank isolation valve is provided on the main pipeline; The pressurizing pipeline is provided with a first solenoid valve; The high-pressure desorption pipeline is provided with a venturi tube, a second solenoid valve, a carbon canister and a third solenoid valve in sequence from the engine to the fuel tank; The oil tank isolation valve, the first solenoid valve, the second solenoid valve, and the third solenoid valve are respectively connected to the control component.

3. The fuel tank leakage detection system according to claim 1, characterized in that: The control component is further configured to determine a pressure drop parameter in the oil tank within a preset time period based on the plurality of third air pressures. If the pressure drop parameter is greater than a preset drop threshold, the oil tank leaks.

4. A fuel tank leakage detection method, characterized in that: The fuel tank leakage detection method is applied to the control component according to any one of claims 1 to 3, and the method comprises: obtaining a first air pressure of an intake manifold of the engine, and if the first air pressure meets a first preset requirement, controlling the main pipeline and the pressurizing pipeline to open, and controlling the high-pressure desorption pipeline to close, so as to introduce the high-pressure gas in the intake manifold into the fuel tank; obtaining a second air pressure in the fuel tank, and if the second air pressure meets a second preset requirement, controlling the pressurization pipeline to close, and obtaining a plurality of third air pressures in the fuel tank within a preset time period; The fuel tank is tested for fuel tank leakage according to the plurality of third air pressures.

5. The method according to claim 4, characterized in that Before obtaining the first air pressure of the intake manifold of the engine, the method further includes: Control the fuel tank isolation valve of the main pipeline to close, control the first solenoid valve of the pressurized pipeline to close, and control the second solenoid valve and the third solenoid valve of the high-pressure desorption pipeline to open, so as to desorb the carbon canister through the high-pressure gas in the intake manifold of the engine.

6. The method according to claim 4, characterized in that The method further comprises: obtaining a first air pressure of an intake manifold of an engine and a fuel tank level of a fuel tank; If the first air pressure meets the first preset requirement and the fuel tank liquid level meets the third preset requirement, the fuel tank isolation valve of the main pipeline is controlled to open, the first solenoid valve of the pressurizing pipeline is controlled to open, and the second solenoid valve and the third solenoid valve of the high-pressure desorption pipeline are controlled to close, so as to introduce the high-pressure gas in the intake manifold into the fuel tank.

7. The method according to claim 4, characterized in that The step of obtaining the second air pressure in the fuel tank, controlling the pressurizing pipeline to close if the second air pressure meets a second preset requirement, and obtaining a plurality of third air pressures in the fuel tank during a preset time period includes: After the tank isolation valve of the main pipeline is controlled to be opened, the first solenoid valve of the pressurizing pipeline is controlled to be opened, and the second solenoid valve and the third solenoid valve of the high-pressure desorption pipeline are controlled to be closed, the timer starts timing; Obtain the second air pressure in the fuel tank in real time; Based on the timer, if the second air pressure meets a second preset requirement within the preset time, the first solenoid valve of the pressurizing pipeline is controlled to be closed, and multiple third air pressures in the oil tank within a preset time period are obtained.

8. The method according to claim 7, characterized in that The method further comprises: Real-time acquisition of the fourth air pressure of the engine intake manifold; If the fourth air pressure is lower than the air pressure threshold or the second air pressure does not meet the second preset requirement within the preset time, the tank isolation valve of the main pipeline is controlled to be closed, the first solenoid valve of the pressurized pipeline is controlled to be closed, and the third solenoid valve of the high-pressure desorption pipeline is controlled to be opened.

9. The method according to claim 7, characterized in that Before obtaining the plurality of third air pressures in the fuel tank during a preset time period, the method further includes: Obtain vehicle speed information and the slip rate of each wheel; determining whether the vehicle speed is stable based on the vehicle speed information; determining whether the road surface on which the vehicle is traveling is bumpy based on the slip rate of each wheel; If the vehicle speed is stable and the road surface on which the vehicle is traveling is not bumpy, a plurality of third air pressures in the fuel tank within a preset time period are obtained.

10. The method according to claim 9, characterized in that Determining whether the road surface on which the vehicle is traveling is bumpy based on the slip rate of each wheel includes: Calculating a slip rate average according to the slip rate of each wheel; determining a slip ratio deviation of each wheel according to the slip ratio of each wheel and the slip ratio mean; If the maximum slip ratio deviation is greater than a preset deviation threshold, the vehicle is traveling on a bumpy road; If the maximum slip ratio deviation is less than or equal to the preset deviation threshold, the road surface on which the vehicle is traveling is not bumpy.

11. The method according to claim 4, characterized in that Performing fuel tank leakage detection on the fuel tank according to the plurality of third air pressures includes: determining a pressure drop parameter in the fuel tank during a preset time period based on the plurality of third air pressures; If the pressure drop parameter is greater than a preset drop threshold, the fuel tank leaks.

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