CN110031160B - Fuel evaporation leakage detection system and method - Google Patents
Fuel evaporation leakage detection system and method Download PDFInfo
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- CN110031160B CN110031160B CN201910444941.7A CN201910444941A CN110031160B CN 110031160 B CN110031160 B CN 110031160B CN 201910444941 A CN201910444941 A CN 201910444941A CN 110031160 B CN110031160 B CN 110031160B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M25/00—Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel or fuel-air mixture
- F02M25/08—Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel or fuel-air mixture adding fuel vapours drawn from engine fuel reservoir
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B51/00—Testing machines, pumps, or pumping installations
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
Abstract
The invention discloses a fuel evaporation leakage detection system and a method, wherein the system comprises: the device comprises an electronic control unit, an air pump, an oil tank, a carbon tank electromagnetic valve and a pressure sensor; the electronic control unit closes the carbon tank electromagnetic valve when detecting that the engine is in an idling state, acquires the current pressure value acquired by the pressure sensor and compares the current pressure value with a preset calibration value, if the current pressure value is smaller than the preset calibration value, the electronic control unit performs reliability detection on the air pump and acquires system pressure when a detection result meets a preset condition, and when the system pressure is smaller than a preset reference pressure, the electronic control unit judges that fuel evaporation leakage exists. The fuel oil pipeline is not required to be vacuumized, the leakage detection difficulty is reduced, meanwhile, the carbon tank electromagnetic valve is closed to detect whether the electromagnetic valve has a fault, the air pump is subjected to fault detection if the electromagnetic valve has no fault, and then whether fuel oil evaporation leakage exists or not is judged through the acquired system pressure when the air pump has no fault, so that the fault part can be accurately positioned, and the leakage detection accuracy is also improved.
Description
Technical Field
The invention relates to the technical field of automobiles, in particular to a fuel evaporation leakage detection system and method.
Background
The fuel system is a very important component in the entire part of the vehicle. Because the petrol in the fuel tank has volatile characteristic, be full of petrol steam in the fuel tank at normal atmospheric temperature usually, in order to can control the atmospheric pressure in the fuel tank, introduce the petrol steam into the engine burning, and reduce petrol steam when Refueling as far as possible and volatilize to the atmosphere, on-vehicle Refueling Vapor Recovery unit (ORVR) is usually adopted, set up the carbon tank between engine and fuel tank promptly, be provided with the active carbon in the carbon tank, this active carbon can adsorb petrol steam, the fuel tank is in communicating state with the carbon tank, petrol steam can get into the carbon tank through the pipeline, and the carbon tank still has the blow vent and communicates with the atmosphere.
In view of the above, On-Board Diagnostics (OBD) regulations have made more stringent definitions of automotive exhaust emission limits. Meanwhile, the fuel pipeline also has more specific requirements: the fuel evaporation leakage in the automobile is monitored, and fuel steam is prevented from leaking into the atmosphere.
At present, there are two fuel evaporation leakage detection schemes, one is to use the vacuum degree attenuation of the fuel evaporation system to judge whether the system leaks, and the other is to use the pressure rising curve of the fuel evaporation system to judge whether the system leaks. The first scheme has the defects that the fuel pipeline needs to be vacuumized, the requirement on the detection environment is high, the second scheme has the defects that other influence factors except pressure are not considered, and the accuracy of the detection result is relatively low.
The above is only for the purpose of assisting understanding of the technical aspects of the present invention, and does not represent an admission that the above is prior art.
Disclosure of Invention
The invention mainly aims to provide a fuel evaporation leakage detection system and a fuel evaporation leakage detection method, and aims to solve the technical problems of high requirements on detection environment and insufficient accuracy in the fuel evaporation leakage detection process in the prior art.
To achieve the above object, the present invention provides a fuel evaporation leakage detection system, comprising: the device comprises an electronic control unit, an air pump, an oil tank, a carbon tank electromagnetic valve and a pressure sensor;
the carbon tank is respectively connected with the oil tank, the air pump and the carbon tank electromagnetic valve through pipelines, the pressure sensor is arranged between the air inlet pipeline and the carbon tank electromagnetic valve, and the electronic control unit is respectively electrically connected with the carbon tank electromagnetic valve, the pressure sensor and the air pump;
the electronic control unit is used for closing the carbon tank electromagnetic valve and acquiring a current pressure value acquired by the pressure sensor when detecting that the engine is in an idle state;
the electronic control unit is further used for comparing the current pressure value with a preset calibration value, and when the current pressure value is smaller than the preset calibration value, performing reliability detection on the air pump and acquiring a detection result;
the electronic control unit is further used for acquiring the system pressure acquired by the pressure sensor when the detection result meets a preset condition, and comparing the system pressure with a preset reference pressure;
and the electronic control unit is also used for judging that fuel evaporation leakage exists when the system pressure is smaller than the preset reference pressure.
Preferably, the electronic control unit is further configured to compare the current pressure value with a preset calibration value, and control the air pump to deliver air to the oil tank when the current pressure value is smaller than the preset calibration value;
the electronic control unit is further used for acquiring a current value corresponding to the air pump in the process of delivering the air to the oil tank by the air pump;
the electronic control unit is further used for detecting whether the current value belongs to a preset current range, and if the current value belongs to the preset current range, acquiring the current frequency of the air pump in the current time period;
and the electronic control unit is also used for detecting whether the current frequency belongs to a preset frequency range or not and acquiring a detection result.
Preferably, the electronic control unit is further configured to determine that the air pump has a fault when it is detected that the current value does not belong to the preset current range.
Preferably, the electronic control unit is further configured to determine that the air pump has a fault when it is detected that the current frequency does not belong to the preset frequency range.
Preferably, the electronic control unit is further configured to compare the current pressure value with a preset calibration value, and determine that the canister electromagnetic valve has a leak when the current pressure value is greater than the preset calibration value.
In addition, in order to achieve the above object, the present invention further provides a fuel evaporation leakage detection method of the fuel evaporation leakage detection system, including:
when the electronic control unit detects that the engine is in an idling state, the carbon tank electromagnetic valve is closed, and a current pressure value acquired by the pressure sensor is acquired;
the electronic control unit compares the current pressure value with a preset calibration value, and when the current pressure value is smaller than the preset calibration value, the electronic control unit performs reliability detection on the air pump and acquires a detection result;
when the detection result meets a preset condition, the electronic control unit acquires system pressure acquired by the pressure sensor and compares the system pressure with a preset reference pressure;
and the electronic control unit judges that fuel evaporation leakage exists when the system pressure is smaller than the preset reference pressure.
Preferably, the step of comparing, by the electronic control unit, the current pressure value with a preset calibration value, and performing reliability detection on the air pump and acquiring a detection result when the current pressure value is smaller than the preset calibration value includes:
the electronic control unit compares the current pressure value with a preset calibration value and controls the air pump to deliver air to the oil tank when the current pressure value is smaller than the preset calibration value;
the electronic control unit acquires a current value corresponding to the air pump in the process of conveying the air to the oil tank by the air pump;
the electronic control unit detects whether the current value belongs to a preset current range, and if the current value belongs to the preset current range, the electronic control unit acquires the current frequency of the air pump in the current time period;
and the electronic control unit detects whether the current frequency belongs to a preset frequency range or not and acquires a detection result.
Preferably, after the step of acquiring, by the electronic control unit, a current value corresponding to the air pump in the process of delivering the air to the oil tank, the method further includes:
and when the electronic control unit detects that the current value does not belong to the preset current range, the electronic control unit judges that the air pump has a fault.
Preferably, after the step of detecting, by the electronic control unit, whether the current frequency belongs to a preset frequency range and acquiring a detection result, the method further includes:
and when the electronic control unit detects that the current frequency does not belong to the preset frequency range, the electronic control unit judges that the air pump has a fault.
Preferably, after the step of closing the canister solenoid valve and acquiring the current pressure value acquired by the pressure sensor by the electronic control unit when the electronic control unit detects that the engine is in an idle state, the method further comprises:
and the electronic control unit compares the current pressure value with a preset calibration value, and judges that the carbon tank electromagnetic valve has leakage when the current pressure value is greater than the preset calibration value.
When an electronic control unit detects that an engine is in an idling state, a carbon tank electromagnetic valve is closed, and a current pressure value acquired by a pressure sensor is acquired; comparing the current pressure value with a preset calibration value, and when the current pressure value is smaller than the preset calibration value, performing reliability detection on the air pump and acquiring a detection result; when the detection result meets a preset condition, acquiring system pressure acquired by a pressure sensor, and comparing the system pressure with a preset reference pressure; and when the system pressure is smaller than the preset reference pressure, judging that fuel evaporation leakage exists. The detection system does not need to vacuumize the fuel pipeline, reduces the difficulty of leakage detection, and meanwhile, because the carbon tank electromagnetic valve is closed to detect whether the electromagnetic valve has a fault or not, if the carbon tank electromagnetic valve has no fault, the air pump is subjected to fault detection, and then whether fuel evaporation leakage exists or not is judged according to the acquired system pressure when the air pump has no fault, the accurate positioning of a fault part can be realized, and the accuracy of leakage detection is also improved.
Drawings
FIG. 1 is a schematic structural diagram of a fuel evaporation leakage detection system in a hardware operating environment according to an embodiment of the present invention;
FIG. 2 is a schematic flow chart of a fuel evaporation leakage detection method according to a first embodiment of the present invention;
fig. 3 is a flowchart illustrating a fuel evaporation leakage detection method according to a second embodiment of the present invention.
The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.
Detailed Description
It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a fuel evaporation leakage detection system in a hardware operating environment according to an embodiment of the present invention.
As shown in fig. 1, the evaporative leak detection system may include: an oil tank 1001, an air pump 1002, a canister 1003, a canister solenoid valve 1004, an electronic control unit 1005, and a pressure sensor 1006.
Those skilled in the art will appreciate that the configuration shown in FIG. 1 does not constitute a limitation of the fuel vapor leak detection system, and may include more or fewer components than shown, or some components in combination, or a different arrangement of components.
The embodiment of the invention provides a fuel evaporation leakage detection system, and referring to fig. 1, fig. 1 is a structural block diagram of the fuel evaporation leakage detection system.
In this embodiment, the fuel evaporation leakage detection system includes: an oil tank 1001, an air pump 1002, a canister 1003, a canister solenoid valve 1004, an electronic control unit 1005, and a pressure sensor 1006.
The canister 1003 is respectively connected to the oil tank 1001, the air pump 1002 and the canister solenoid valve 1004 through pipelines, the pressure sensor 1006 is disposed between an air inlet pipeline (also called an intake manifold) and the canister solenoid valve 1004, and the electronic control unit 1005 is respectively electrically connected to the canister solenoid valve 1004, the pressure sensor 1006 and the air pump 1002.
In this embodiment, the electronic control unit 1005 is configured to close the canister electromagnetic valve 1004 when it is detected that the engine is in an idle state, and obtain a current pressure value acquired by the pressure sensor 1006;
it should be understood that an Electronic Control Unit (ECU), also known as a "vehicle computer" or an "on-board computer", generally has a fault self-diagnosis and protection function, and when a fault occurs in the system, it can automatically record a fault code in a Random Access Memory (RAM) and use a protection measure to read a replacement program from a native program to maintain the operation of the engine. The idling refers to a working condition of the automobile, and the idling is called when an engine of the automobile idles, namely, the gear of the automobile is neutral. The canister solenoid valve is a device installed in a vehicle for reducing air pollution due to evaporative emissions of fuel while increasing fuel efficiency.
It will be appreciated that the pressure sensor 1006 in this embodiment is used to monitor the pressure (or pressure signal) in the line. Under normal conditions, when carbon canister solenoid valve 1004 is closed, a sealed chamber with stable pressure should belong to between carbon canister solenoid valve 1004 and the air inlet pipeline, if the pressure value that pressure sensor 1006 gathered is greater than a predetermined calibration value at this moment, it indicates that carbon canister solenoid valve 1004 has revealed or the trouble. That is to say, the electronic control unit 1005 in this embodiment is further configured to compare the current pressure value with the preset calibration value, and determine that there is a leak in the canister solenoid valve 1004 when the current pressure value is greater than the preset calibration value.
Of course, if the collected pressure value is smaller than the calibrated value, it indicates that further detection of whether there is a fault or a leak in other locations or components is required.
In a specific implementation, when the automobile ignition engine is in an idle state, the electronic control unit 1005 firstly closes the canister electromagnetic valve 1004, and then obtains a pressure value currently acquired by the pressure sensor 1006.
The electronic control unit 1005 is further configured to compare the current pressure value with a preset calibration value, and when the current pressure value is smaller than the preset calibration value, perform reliability detection on the air pump 1002 and obtain a detection result;
it should be noted that the preset calibration value may be a standard pressure value between a canister solenoid valve and an air intake pipe, which is set according to an idle state of the vehicle engine under normal conditions. Of course, the predetermined calibration value may be a range of values to improve the accuracy of the leak detection. The reliability detection may be that the electronic control unit 1005 controls the air pump 1002 and the valves therein to operate, and then performs a rationality judgment on the current flowing through the air pump 1002 and the current frequency, that is, a rationality judgment is performed to judge whether the current and the current frequency belong to respective corresponding reasonable value ranges, which may be set according to practical experience, which is not limited in this embodiment.
In a specific implementation, after the current pressure value is obtained, the electronic control unit 1005 may compare the current pressure value with a preset calibration value, and if the current pressure value is smaller than the preset calibration value, it indicates that the canister electromagnetic valve 1004 has no leakage or failure, and further needs to perform reliability detection on the air pump 1002, and then further detects fuel evaporation leakage according to a detection result.
The electronic control unit 1005 is further configured to, when the detection result meets a preset condition, acquire a system pressure acquired by the pressure sensor 1006, and compare the system pressure with a preset reference pressure;
it should be noted that the detection result meets a preset condition, that is, the current flowing through the air pump 1002 and the current frequency corresponding to the current both belong to a reasonable value range. The system pressure is the system pressure value of the whole pipeline system (in this embodiment, composed of the oil tank 1001, the pump 1002, the carbon tank 1003, the carbon tank electromagnetic valve 1004, and the pressure sensor 1006) when the air pump 1002 works.
It should be understood that the preset reference pressure is a preset reference pressure for determining whether a leakage or a fault exists in the pipeline system, and the specific value is not limited in this embodiment.
In a specific implementation, when detecting that the detection result satisfies a preset condition, the electronic control unit 1005 acquires the system pressure acquired by the pressure sensor 1006, compares the system pressure with a preset reference pressure, and then determines whether there is a leak or a fault according to the comparison result.
The electronic control unit 1005 is further configured to determine that there is fuel evaporation leakage when the system pressure is less than the preset reference pressure.
In a specific implementation, the electronic control unit 1005 determines that there is fuel evaporation leakage when detecting that the system pressure is less than the preset reference pressure; and on the contrary, if the system pressure is greater than the preset reference pressure, the fuel evaporation leakage is judged to be absent.
When the electronic control unit detects that the engine is in an idling state, the carbon tank electromagnetic valve is closed, and a current pressure value acquired by the pressure sensor is acquired; comparing the current pressure value with a preset calibration value, and when the current pressure value is smaller than the preset calibration value, performing reliability detection on the air pump and acquiring a detection result; when the detection result meets a preset condition, acquiring system pressure acquired by a pressure sensor, and comparing the system pressure with a preset reference pressure; and when the system pressure is smaller than the preset reference pressure, judging that fuel evaporation leakage exists. The detection system of the embodiment does not need to vacuumize the fuel pipeline, so that the leakage detection difficulty is reduced, meanwhile, because the carbon tank electromagnetic valve is closed to detect whether the electromagnetic valve has a fault or not, if the carbon tank electromagnetic valve has no fault, the air pump is subjected to fault detection, and then whether fuel evaporation leakage exists or not is judged according to the acquired system pressure when the air pump has no fault, so that the fault part can be accurately positioned, and the leakage detection accuracy is also improved.
A second embodiment of the evaporative leak detection system of the present invention is proposed based on the above-described first embodiment.
In this embodiment, the electronic control unit 1005 is further configured to compare the current pressure value with the preset calibration value, and control the air pump 1002 to deliver air to the oil tank 1001 when the current pressure value is smaller than the preset calibration value;
it should be understood that if the electronic control unit 1005 detects that the current pressure value is less than the preset calibration value, it indicates that there is no leakage or failure of the canister solenoid valve 1004, and further reliability detection of the air pump 1002 is required.
Specifically, the electronic control unit 1005 may activate the air pump 1002, and control the air pump 1002 to deliver air to the oil tank 1001, so as to increase the air pressure in the oil tank.
The electronic control unit 1005 is further configured to obtain a current value corresponding to the air pump 1002 in the process of delivering the air to the oil tank 1001 by the air pump 1002;
in specific implementation, after the electronic control unit 1005 starts the air pump 1002 by pulling down the corresponding PIN, it will also collect a current value corresponding to the air pump 1002 during the process of delivering air from the air pump 1002 to the oil tank 1001, and then detect whether the current value belongs to a preset current range, and if not, it may directly determine that the air pump 1002 has a fault.
The electronic control unit 1005 is further configured to detect whether the current value belongs to a preset current range, and if so, obtain a current frequency of the air pump 1002 at the current time interval;
in a specific implementation, if the electronic control unit 1005 detects that the current value belongs to the preset current range, it is further required to obtain a current frequency of the air pump 1002 in the current period, and detect whether the current frequency of the air pump 1002 during operation is normal, so as to determine whether the air pump 1002 is reliable.
The electronic control unit 1005 is further configured to detect whether the current frequency belongs to a preset frequency range, and obtain a detection result.
In a specific implementation, after obtaining the current frequency, the electronic control unit 1005 further detects whether the current frequency belongs to a preset frequency range, and if so (that is, a detection result meets a preset condition), it indicates that the air pump 1002 is reliable, and the pressure of the pipeline system can be tested and compared.
Further, if the electronic control unit 1005 detects that the current frequency does not belong to the preset frequency range, it may directly determine that the air pump has a fault, and at this time, it is not necessary to perform system pressure detection, so as to reduce the detection flow while ensuring the accuracy of the detection result.
The electronic control unit of the embodiment compares the current pressure value with a preset calibration value, and controls the air pump to deliver air to the oil tank when the current pressure value is smaller than the preset calibration value; acquiring a current value corresponding to the air pump in the process of delivering air to the oil tank by the air pump; detecting whether the current value belongs to a preset current range or not, and if so, acquiring the current frequency of the air pump in the current time period; whether the current frequency belongs to the preset frequency range or not is detected, and a detection result is obtained, when the air pump delivers air to the oil tank, whether the current value of the air pump and the current frequency are in a reasonable numerical range or not is detected, whether the air pump has a fault or not can be judged according to the detection result, the position where the fault occurs can be accurately diagnosed when the system leaks, and the accuracy of leakage detection is improved.
Based on the fuel evaporation leakage detection system, the invention also provides a fuel evaporation leakage detection method.
Referring to fig. 2, fig. 2 is a schematic flow chart of a fuel evaporation leakage detection method according to a first embodiment of the present invention.
In this embodiment, the fuel evaporation leakage detection method includes the following steps:
step S10: when the electronic control unit detects that the engine is in an idling state, the carbon tank electromagnetic valve is closed, and a current pressure value acquired by the pressure sensor is acquired;
it should be understood that an Electronic Control Unit (ECU), also known as a "vehicle computer" or an "on-board computer", generally has a fault self-diagnosis and protection function, and when a fault occurs in the system, it can automatically record a fault code in a Random Access Memory (RAM) and use a protection measure to read a replacement program from a native program to maintain the operation of the engine. The idling refers to a working condition of the automobile, and the idling is called when an engine of the automobile idles, namely, the gear of the automobile is neutral. The canister solenoid valve is a device installed in a vehicle for reducing air pollution due to evaporative emissions of fuel while increasing fuel efficiency.
It will be appreciated that the pressure sensor in this embodiment is used to monitor the pressure (or pressure signal) in the line. Under normal conditions, when the carbon tank solenoid valve was closed, should belong to a stable seal chamber of pressure between carbon tank solenoid valve and the air inlet pipe way, if the pressure value that pressure sensor gathered at this moment is greater than a predetermined calibration value, then show that the carbon tank solenoid valve exists and reveal or the trouble. That is to say, the electronic control unit in this embodiment further compares the current pressure value with the preset calibration value, and determines that the canister electromagnetic valve has a leak when the current pressure value is greater than the preset calibration value.
Of course, if the collected pressure value is smaller than the calibrated value, it indicates that further detection of whether there is a fault or a leak in other locations or components is required.
In the specific implementation, when an automobile ignition engine is in an idling state, an electronic control unit firstly closes a carbon tank electromagnetic valve and then obtains a pressure value currently acquired by a pressure sensor.
Step S20: the electronic control unit compares the current pressure value with a preset calibration value, and when the current pressure value is smaller than the preset calibration value, the electronic control unit performs reliability detection on the air pump and acquires a detection result;
it should be noted that the preset calibration value may be a standard pressure value between a canister solenoid valve and an air intake pipe, which is set according to an idle state of the vehicle engine under normal conditions. Of course, the predetermined calibration value may be a range of values to improve the accuracy of the leak detection. The reliability detection may be that the electronic control unit controls the air pump and a valve inside the air pump to operate, and then performs a rationality judgment on the current and the current frequency flowing through the air pump, so-called rationality judgment, that is, whether the current and the current frequency belong to respective corresponding reasonable value ranges, where the reasonable value ranges may be set according to practical experience, and this embodiment does not limit this.
In specific implementation, after the current pressure value is obtained, the electronic control unit may compare the current pressure value with a preset calibration value, and if the current pressure value is smaller than the preset calibration value, it indicates that the canister electromagnetic valve does not leak or has a fault, and it is necessary to further perform reliability detection on the air pump, and then further detect fuel evaporation leakage according to a detection result.
Step S30: when the detection result meets a preset condition, the electronic control unit acquires system pressure acquired by the pressure sensor and compares the system pressure with a preset reference pressure;
it should be noted that the detection result meets a preset condition, that is, the current flowing through the air pump and the current frequency corresponding to the current both belong to a reasonable value range. The system pressure is the system pressure value of the whole pipeline system (in this embodiment, composed of an oil tank, a pump gas, a carbon tank electromagnetic valve and a pressure sensor) when the air pump works.
It should be understood that the preset reference pressure is a preset reference pressure for determining whether a leakage or a fault exists in the pipeline system, and the specific value is not limited in this embodiment.
In a specific implementation, when detecting that the detection result meets a preset condition, the electronic control unit acquires system pressure acquired by the pressure sensor, compares the system pressure with a preset reference pressure, and determines whether leakage or failure exists according to the comparison result.
Step S40: and the electronic control unit judges that fuel evaporation leakage exists when the system pressure is smaller than the preset reference pressure.
In a specific implementation, the electronic control unit judges that fuel evaporation leakage exists when detecting that the system pressure is smaller than the preset reference pressure; and on the contrary, if the system pressure is greater than the preset reference pressure, the fuel evaporation leakage is judged to be absent.
When the electronic control unit detects that the engine is in an idling state, the carbon tank electromagnetic valve is closed, and a current pressure value acquired by the pressure sensor is acquired; comparing the current pressure value with a preset calibration value, and when the current pressure value is smaller than the preset calibration value, performing reliability detection on the air pump and acquiring a detection result; when the detection result meets a preset condition, acquiring system pressure acquired by a pressure sensor, and comparing the system pressure with a preset reference pressure; and when the system pressure is smaller than the preset reference pressure, judging that fuel evaporation leakage exists. The detection system of the embodiment does not need to vacuumize the fuel pipeline, so that the leakage detection difficulty is reduced, meanwhile, because the carbon tank electromagnetic valve is closed to detect whether the electromagnetic valve has a fault or not, if the carbon tank electromagnetic valve has no fault, the air pump is subjected to fault detection, and then whether fuel evaporation leakage exists or not is judged according to the acquired system pressure when the air pump has no fault, so that the fault part can be accurately positioned, and the leakage detection accuracy is also improved.
Referring to fig. 3, fig. 3 is a schematic flow chart of a fuel evaporation leakage detection method according to a second embodiment of the present invention.
Based on the first embodiment of the fuel evaporation leakage detection method, the step S20 in this embodiment includes:
step S201: the electronic control unit compares the current pressure value with a preset calibration value and controls the air pump to deliver air to the oil tank when the current pressure value is smaller than the preset calibration value;
it should be understood that if the electronic control unit detects that the current pressure value is less than the preset calibration value, it indicates that there is no leakage or failure of the canister solenoid valve, and it is necessary to further perform reliability detection on the air pump.
Specifically, the electronic control unit may start the air pump and control the air pump to deliver air to the oil tank, so as to increase the air pressure in the oil tank.
Step S202: the electronic control unit acquires a current value corresponding to the air pump in the process of conveying the air to the oil tank by the air pump;
in the specific implementation, after the electronic control unit starts the air pump by pulling down the corresponding PIN foot, the electronic control unit also collects the current value corresponding to the air pump in the process of delivering air from the air pump to the oil tank, and then detects whether the current value belongs to a preset current range, if not, the electronic control unit can directly judge that the air pump has a fault.
Step S203: the electronic control unit detects whether the current value belongs to a preset current range, and if the current value belongs to the preset current range, the electronic control unit acquires the current frequency of the air pump in the current time period;
in a specific implementation, if the electronic control unit detects that the current value belongs to a preset current range, the current frequency of the air pump in the current time period is further acquired, and whether the current frequency of the air pump during operation is normal or not is detected to determine whether the air pump is reliable or not.
Step S204: and the electronic control unit detects whether the current frequency belongs to a preset frequency range or not and acquires a detection result.
In a specific implementation, after obtaining the current frequency, the electronic control unit further detects whether the current frequency belongs to a preset frequency range, and if the current frequency belongs to the preset frequency range (that is, a detection result meets a preset condition), it is determined that the air pump is reliable, and the pressure of the pipeline system can be tested and compared.
Further, if the electronic control unit detects that the current frequency does not belong to the preset frequency range, the air pump can be directly judged to have a fault, and at the moment, system pressure detection is not needed, so that the accuracy of a detection result is ensured, and meanwhile, the detection flow is reduced.
The electronic control unit of the embodiment compares the current pressure value with a preset calibration value, and controls the air pump to deliver air to the oil tank when the current pressure value is smaller than the preset calibration value; acquiring a current value corresponding to the air pump in the process of delivering air to the oil tank by the air pump; detecting whether the current value belongs to a preset current range or not, and if so, acquiring the current frequency of the air pump in the current time period; whether the current frequency belongs to the preset frequency range or not is detected, and a detection result is obtained, when the air pump delivers air to the oil tank, whether the current value of the air pump and the current frequency are in a reasonable numerical range or not is detected, whether the air pump has a fault or not can be judged according to the detection result, the position where the fault occurs can be accurately diagnosed when the system leaks, and the accuracy of leakage detection is improved.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.
The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.
Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solutions of the present invention may be embodied in the form of a software product, which is stored in a storage medium (e.g., a rom/ram, a magnetic disk, an optical disk) and includes instructions for enabling a terminal device (e.g., a mobile phone, a computer, a server, an air conditioner, or a network device) to execute the method according to the embodiments of the present invention.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (10)
1. A fuel evaporative leak detection system, the system comprising: the device comprises an electronic control unit, an air pump, an oil tank, a carbon tank electromagnetic valve and a pressure sensor;
the carbon tank is respectively connected with the oil tank, the air pump and the carbon tank electromagnetic valve through pipelines, the pressure sensor is arranged between the air inlet pipeline and the carbon tank electromagnetic valve, and the electronic control unit is respectively electrically connected with the carbon tank electromagnetic valve, the pressure sensor and the air pump;
the electronic control unit is used for closing the carbon tank electromagnetic valve and acquiring a current pressure value acquired by the pressure sensor when detecting that the engine is in an idle state;
the electronic control unit is further used for comparing the current pressure value with a preset calibration value, and when the current pressure value is smaller than the preset calibration value, performing reliability detection on the air pump and acquiring a detection result;
the electronic control unit is further configured to acquire a system pressure acquired by the pressure sensor when the detection result meets a preset condition, and compare the system pressure with a preset reference pressure, wherein the system pressure is a pressure value acquired by the pressure sensor when the air pump normally works;
and the electronic control unit is also used for judging that fuel evaporation leakage exists when the system pressure is smaller than the preset reference pressure.
2. The system of claim 1, wherein the electronic control unit is further configured to compare the current pressure value with the preset calibration value, and to control the air pump to deliver air to the oil tank when the current pressure value is smaller than the preset calibration value;
the electronic control unit is further used for acquiring a current value corresponding to the air pump in the process of delivering the air to the oil tank by the air pump;
the electronic control unit is further used for detecting whether the current value belongs to a preset current range, and if the current value belongs to the preset current range, acquiring the current frequency of the air pump in the current time period;
and the electronic control unit is also used for detecting whether the current frequency belongs to a preset frequency range or not and acquiring a detection result.
3. The system of claim 2, wherein the electronic control unit is further configured to determine that the air pump is malfunctioning when the current value is detected to be outside the preset current range.
4. The system of claim 2, wherein the electronic control unit is further configured to determine that the air pump is malfunctioning when the current frequency is detected to be outside the preset frequency range.
5. The system of claim 2, wherein the electronic control unit is further configured to compare the current pressure value to the preset calibration value and determine that a leak exists in the canister solenoid valve when the current pressure value is greater than the preset calibration value.
6. A fuel evaporation leakage detection method based on the fuel evaporation leakage detection system according to any one of claims 1 to 5, characterized by comprising:
when the electronic control unit detects that the engine is in an idling state, the carbon tank electromagnetic valve is closed, and a current pressure value acquired by the pressure sensor is acquired;
the electronic control unit compares the current pressure value with a preset calibration value, and when the current pressure value is smaller than the preset calibration value, the electronic control unit performs reliability detection on the air pump and acquires a detection result;
when the detection result meets a preset condition, the electronic control unit acquires system pressure acquired by the pressure sensor and compares the system pressure with a preset reference pressure, wherein the system pressure is a pressure value acquired by the pressure sensor when the air pump works normally;
and the electronic control unit judges that fuel evaporation leakage exists when the system pressure is smaller than the preset reference pressure.
7. The method of claim 6, wherein the step of comparing the current pressure value with a preset calibration value by the electronic control unit, and detecting the reliability of the air pump and obtaining the detection result when the current pressure value is less than the preset calibration value comprises:
the electronic control unit compares the current pressure value with a preset calibration value and controls the air pump to deliver air to the oil tank when the current pressure value is smaller than the preset calibration value;
the electronic control unit acquires a current value corresponding to the air pump in the process of conveying the air to the oil tank by the air pump;
the electronic control unit detects whether the current value belongs to a preset current range, and if the current value belongs to the preset current range, the electronic control unit acquires the current frequency of the air pump in the current time period;
and the electronic control unit detects whether the current frequency belongs to a preset frequency range or not and acquires a detection result.
8. The method according to claim 7, wherein after the step of the electronic control unit obtaining the current value corresponding to the air pump during the process of delivering the air to the oil tank, the method further comprises:
and when the electronic control unit detects that the current value does not belong to the preset current range, the electronic control unit judges that the air pump has a fault.
9. The method of claim 7, wherein after the step of the electronic control unit detecting whether the current frequency falls within a preset frequency range and obtaining the detection result, the method further comprises:
and when the electronic control unit detects that the current frequency does not belong to the preset frequency range, the electronic control unit judges that the air pump has a fault.
10. The method of claim 7, wherein after the step of the electronic control unit closing the canister solenoid valve and acquiring the current pressure value acquired by the pressure sensor upon detection of an engine idling, the method further comprises:
and the electronic control unit compares the current pressure value with a preset calibration value, and judges that the carbon tank electromagnetic valve has leakage when the current pressure value is greater than the preset calibration value.
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| CN112610367B (en) * | 2020-12-18 | 2022-10-04 | 上汽大通汽车有限公司 | Fault diagnosis method for carbon canister electromagnetic valve |
| CN113931728B (en) * | 2021-01-19 | 2023-03-28 | 吉利汽车研究院（宁波）有限公司 | Oil vapor control method, device and system and storage medium |
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| CN114618058A (en) * | 2022-03-11 | 2022-06-14 | 浙江宜格企业管理集团有限公司 | Gas pressure control method, system and equipment of beauty instrument |
| CN116026532A (en) * | 2023-03-27 | 2023-04-28 | 苏州恩都法汽车系统股份有限公司 | Sectional type leakage diagnosis system, sectional type leakage diagnosis method and vehicle |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5641899A (en) * | 1996-03-05 | 1997-06-24 | Chrysler Corporation | Method of checking for purge flow in an evaporative emission control system |
| JPH09242633A (en) * | 1996-03-01 | 1997-09-16 | Robert Bosch Gmbh | Airtightness testing method for tank system of vehicle with internal combustion engine |
| JP3459247B2 (en) * | 1991-07-24 | 2003-10-20 | ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツング | Tank exhaust system and vehicle with tank exhaust system, and method and apparatus for testing the function of tank exhaust system |
| CN1573070A (en) * | 2003-05-21 | 2005-02-02 | 本田技研工业株式会社 | Failure diagnosis apparatus for evaporative fuel processing system |
| CN1601075A (en) * | 2003-09-22 | 2005-03-30 | 日立优喜雅汽车配件有限公司 | Diagnoser and method for air transferring appts |
| CN101576031A (en) * | 2008-05-09 | 2009-11-11 | 日产自动车株式会社 | Leak diagnostic apparatus for an evaporative emission control system |
| CN105156210A (en) * | 2015-09-18 | 2015-12-16 | 亚普汽车部件股份有限公司 | Fuel oil box evaporation emission system leakage detection device and method |
| CN107709745A (en) * | 2015-06-23 | 2018-02-16 | 日产自动车株式会社 | The diagnostic device of evaporated fuel treating apparatus |
| CN109441671A (en) * | 2018-10-26 | 2019-03-08 | 安徽江淮汽车集团股份有限公司 | A kind of low diagnostic system and method that pipeline is desorbed of engine |
-
2019
- 2019-05-24 CN CN201910444941.7A patent/CN110031160B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3459247B2 (en) * | 1991-07-24 | 2003-10-20 | ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツング | Tank exhaust system and vehicle with tank exhaust system, and method and apparatus for testing the function of tank exhaust system |
| JPH09242633A (en) * | 1996-03-01 | 1997-09-16 | Robert Bosch Gmbh | Airtightness testing method for tank system of vehicle with internal combustion engine |
| US5641899A (en) * | 1996-03-05 | 1997-06-24 | Chrysler Corporation | Method of checking for purge flow in an evaporative emission control system |
| CN1573070A (en) * | 2003-05-21 | 2005-02-02 | 本田技研工业株式会社 | Failure diagnosis apparatus for evaporative fuel processing system |
| CN1601075A (en) * | 2003-09-22 | 2005-03-30 | 日立优喜雅汽车配件有限公司 | Diagnoser and method for air transferring appts |
| CN101576031A (en) * | 2008-05-09 | 2009-11-11 | 日产自动车株式会社 | Leak diagnostic apparatus for an evaporative emission control system |
| CN107709745A (en) * | 2015-06-23 | 2018-02-16 | 日产自动车株式会社 | The diagnostic device of evaporated fuel treating apparatus |
| CN105156210A (en) * | 2015-09-18 | 2015-12-16 | 亚普汽车部件股份有限公司 | Fuel oil box evaporation emission system leakage detection device and method |
| CN109441671A (en) * | 2018-10-26 | 2019-03-08 | 安徽江淮汽车集团股份有限公司 | A kind of low diagnostic system and method that pipeline is desorbed of engine |
Non-Patent Citations (1)
| Title |
|---|
| 带泄漏诊断功能的燃油蒸发物排放控制系统;李强;《汽车维修与保养》;20120331(第3(2012)期);第74-76页 * |
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