CN111332228B - Oil tank leakage diagnosis method and system and automobile - Google Patents
Oil tank leakage diagnosis method and system and automobile Download PDFInfo
- Publication number
- CN111332228B CN111332228B CN202010089931.9A CN202010089931A CN111332228B CN 111332228 B CN111332228 B CN 111332228B CN 202010089931 A CN202010089931 A CN 202010089931A CN 111332228 B CN111332228 B CN 111332228B
- Authority
- CN
- China
- Prior art keywords
- pressure
- leakage
- oil tank
- liquid level
- tank assembly
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
- B60R16/00—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for
- B60R16/02—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements
- B60R16/023—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements for transmission of signals between vehicle parts or subsystems
- B60R16/0231—Circuits relating to the driving or the functioning of the vehicle
- B60R16/0232—Circuits relating to the driving or the functioning of the vehicle for measuring vehicle parameters and indicating critical, abnormal or dangerous conditions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
- B60K15/03—Fuel tanks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
- B60K15/03—Fuel tanks
- B60K2015/03118—Multiple tanks, i.e. two or more separate tanks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- B60K15/00—Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or construction of fuel tanks
- B60K15/03—Fuel tanks
- B60K2015/03328—Arrangements or special measures related to fuel tanks or fuel handling
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Automation & Control Theory (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Examining Or Testing Airtightness (AREA)
Abstract
The invention discloses an oil tank leakage diagnosis method, an oil tank leakage diagnosis system and an automobile, wherein the method is used for the oil tank leakage diagnosis system, the oil tank leakage diagnosis system comprises an oil tank assembly and a whole automobile controller, and the oil tank assembly comprises a plurality of oil tanks connected in series; the method is executed by a vehicle control unit and comprises the following steps: acquiring a reference liquid level of the oil tank assembly and a first leakage pressure corresponding to the reference liquid level; acquiring the current liquid level of each oil tank, and determining a second leakage pressure of the oil tank assembly; carrying out negative pressure equalization processing on the oil tank assembly; and comparing the actual pressure of the oil tank assembly with the second leakage pressure to obtain an oil tank leakage diagnosis result of the oil tank assembly. The invention solves the problems that the existing diagnosis method is not suitable for multi-oil-tank leakage diagnosis and the reliability of the diagnosis result is influenced by fuel volatilization.
Description
Technical Field
The invention relates to the technical field of oil tanks, in particular to an oil tank leakage diagnosis method and system and an automobile.
Background
The fuel system functions to supply a quantity of clean, well atomized gasoline to the engine as required by the operating conditions of the engine to mix with a quantity of air to form a combustible mixture. At the same time, the fuel system also needs to store a considerable amount of fuel to ensure that the vehicle has a considerable driving range. The fuel oil used by the current automobiles is mainly gasoline and diesel oil. With the increasing of the automobile keeping quantity year by year, the environmental pollution problem caused by the automobile emission and leakage is not ignored. Systems for checking the functionality and the tightness of fuel tanks in motor vehicles are regulated by law in some countries. In order to detect leaks in the tank system, different diagnostic methods are known, so that not only methods for carrying out diagnostics by means of overpressure, but also methods for carrying out diagnostics based on underpressure are known. One approach is to use negative pressure behind the throttle while the engine is idling for leak diagnosis. The leakage diagnosis of the fuel tank is usually based on a single fuel tank, is not suitable for a plurality of fuel tanks, and fuel volatilization can interfere with a pressure signal in the diagnosis process, so that the reliability of the diagnosis result is influenced to a certain extent.
Disclosure of Invention
The invention aims to provide a fuel tank leakage diagnosis method, a fuel tank leakage diagnosis system and an automobile, and solves the problems that the existing diagnosis method is not suitable for multi-fuel tank leakage diagnosis, and the reliability of diagnosis results is influenced by fuel volatilization.
In order to solve the technical problem, the invention provides a method for diagnosing the leakage of the oil tank, which is used for an oil tank leakage diagnosing system, wherein the oil tank leakage diagnosing system comprises an oil tank assembly and a vehicle control unit, and the oil tank assembly comprises a plurality of oil tanks connected in series; the method is executed by a vehicle control unit and comprises the following steps: acquiring a reference liquid level of the oil tank assembly and a first leakage pressure corresponding to the reference liquid level, wherein the reference liquid level of the oil tank assembly comprises a first liquid level of each oil tank; acquiring the current liquid level of each oil tank, and determining the second leakage pressure of the oil tank assembly according to the first leakage pressure, the current liquid level of each oil tank and the first liquid level; carrying out negative pressure equalization processing on the oil tank assembly; acquiring the actual pressure of the oil tank assembly subjected to the negative pressure equalization treatment; and comparing the actual pressure of the oil tank assembly with the second leakage pressure to obtain an oil tank leakage diagnosis result of the oil tank assembly.
Further, the fuel tank leakage diagnosis system further comprises a scavenging pipe, an activated carbon container, a first solenoid valve, a second solenoid valve, a pressure sensor and a liquid level sensor arranged on each fuel tank, wherein the fuel tank assembly is connected with an engine intake manifold through the scavenging pipe, the activated carbon container is arranged in the scavenging pipe and comprises an air inlet end, an air outlet end and a breathing port, the air inlet end is connected with the fuel tank assembly, the air outlet end is connected with the engine intake manifold, the first solenoid valve is arranged at the breathing port, the second solenoid valve is arranged between the air outlet end and the engine intake manifold, and the pressure sensor is used for detecting the pressure of the fuel tank assembly; the negative pressure equalization processing of the oil tank assembly comprises the following steps: controlling the second electromagnetic valve to change from a closed state to an open state so as to enable air to enter the engine intake manifold; controlling the first electromagnetic valve to change from an open state to a closed state so that the pressure of the plurality of oil tanks is equal to the pressure of the engine intake manifold; and controlling the second electromagnetic valve to be changed from an open state to a closed state so as to close the plurality of oil tanks and pipelines communicated with the plurality of oil tanks.
Further, the step of obtaining the actual pressure of the oil tank assembly subjected to the negative pressure equalization processing further includes: and acquiring the actual pressure of the oil tank assembly at intervals of the preset time period.
Further, the step of determining a second leakage pressure of the tank assembly according to the first leakage pressure, the current liquid level of each of the tanks and the first liquid level further comprises: calculating a first difference value between the current liquid level of each oil tank and the maximum liquid level corresponding to the oil tank, calculating a second difference value between the first liquid level of each oil tank and the maximum liquid level corresponding to the oil tank, calculating a ratio between the first difference value and the second difference value of each oil tank, taking the ratio as a pressure change ratio, calculating a ratio between the liquid surface area of each oil tank and the sum of the liquid surface areas of all the oil tanks, taking the ratio as a weight coefficient, calculating the product of the pressure change ratio of each oil tank and the weight coefficient corresponding to the oil tank, recording the product as a current pressure change ratio, calculating the sum of the current pressure change ratios of all the oil tanks, and recording the sum as a system pressure change ratio; calculating the product of the system pressure change ratio and the first leakage pressure to obtain a second leakage pressure.
Further, the step of comparing the actual pressure of the tank assembly with the second leakage pressure to obtain a tank leakage diagnosis result further includes: if the actual pressure is smaller than the second leakage pressure, the oil tank leakage diagnosis result is no leakage; and if the actual pressure is greater than or equal to the second leakage pressure, the oil tank leakage diagnosis result is leakage.
Further, the first leakage pressure includes a first leakage pressure range upper limit and a first leakage pressure range lower limit.
Further, the second leakage pressure includes a second leakage pressure range upper limit and a second leakage pressure range lower limit.
Further, the step of comparing the actual pressure of the tank assembly with the second leakage pressure to obtain a tank leakage diagnosis result further includes: if the actual pressure is less than or equal to the lower limit of the second leakage pressure range, the oil tank leakage diagnosis result is no leakage; if the actual pressure is between the upper limit of the second leakage pressure range and the lower limit of the second leakage pressure range, the oil tank leakage diagnosis result is that the oil tank does not leak seriously; and if the actual pressure is greater than or equal to the upper limit of the second leakage pressure range, the oil tank leakage diagnosis result is serious leakage.
The embodiment of the invention also provides an oil tank leakage diagnosis system which comprises an oil tank assembly and a vehicle control unit, wherein the oil tank assembly comprises a plurality of oil tanks connected in series; the vehicle control unit comprises: the device comprises a first acquisition module, a second acquisition module, a determination module, a processing module, a third acquisition module and a comparison module; the first acquisition module is used for acquiring a reference liquid level of the oil tank assembly and a first leakage pressure corresponding to the reference liquid level, wherein the reference liquid level of the oil tank assembly comprises the first liquid level of each oil tank; the second acquisition module is used for acquiring the current liquid level of each oil tank; the determining module comprises determining a second leakage pressure of the tank assembly based on the first leakage pressure, the current liquid level and the first liquid level of each of the tanks; the processing module performs negative pressure equalization processing on the oil tank assembly; the third acquisition module is used for acquiring the actual pressure of the oil tank assembly subjected to the negative pressure equalization treatment; the comparison module compares the actual pressure of the oil tank assembly with the second leakage pressure to obtain an oil tank leakage diagnosis result of the oil tank assembly.
The embodiment of the invention also provides an automobile which is provided with the oil tank leakage diagnosis system.
The implementation of the invention has the following beneficial effects:
according to the invention, the plurality of oil tanks in the oil tank assembly are connected in series for diagnosis, the oil tanks are large in size after the plurality of oil tanks are connected in series, the negative pressure pumping capacity is strong after negative pressure equalization treatment, and the detection speed is high; the system is slightly changed, the cost is saved, meanwhile, correction is carried out according to the liquid level of the oil tank, the influence of different oil tank liquid levels on the volatilization rate of fuel oil is considered, the second leakage pressure serving as a diagnostic standard is determined according to the liquid level of the oil tank, and the reliability of the oil tank leakage diagnostic result is improved by connecting the diagnostic standard with the liquid level of the oil tank.
Drawings
In order to more clearly illustrate the technical solution of the present invention, the drawings needed for the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
Fig. 1 is a schematic flow chart illustrating steps of a tank leakage diagnosis method according to an embodiment of the present invention.
Fig. 2 is a schematic structural diagram of a tank leakage diagnosis system provided by an embodiment of the invention.
Fig. 3 is a schematic flow chart of steps of the negative pressure equalization process according to the embodiment of the present invention.
Fig. 4 is a flowchart illustrating steps for determining the second leakage pressure according to an embodiment of the present invention.
FIG. 5 is a schematic diagram of the diagnostic results provided by the embodiment of the present invention.
Fig. 6 is a schematic structural diagram of a vehicle control unit according to an embodiment of the present invention.
Wherein the reference numerals in the figures correspond to: 810-a first acquisition module, 820-a second acquisition module, 830-a determination module, 840-a processing module, 850-a third acquisition module, 860-a comparison module, 910-a ventilation tube, 920-an activated carbon container, 921-an intake port, 922-an exhaust port, 923-a breathing port, 930-a first solenoid valve, 940-a second solenoid valve, 950-an engine intake manifold, 960-a throttle valve.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without any inventive step, are within the scope of the present invention.
In the following description, for clarity and conciseness of description, not all of the various components shown in the figures have been described, which are shown to provide those of ordinary skill in the art with a fully enabling disclosure of the present invention. The operation of many of the components is familiar and obvious to those skilled in the art.
Furthermore, the terms "first", "second" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, whereby features defined as "first", "second" may explicitly or implicitly include one or more of those features, in the description of the invention "plurality" means two or more unless explicitly defined otherwise.
The oil tank leakage diagnosis method provided by the embodiment is used for an oil tank leakage diagnosis system, the oil tank leakage diagnosis system comprises an oil tank assembly and a vehicle control unit, and the oil tank assembly comprises a plurality of oil tanks connected in series; because the oil tanks are connected in series, the oil tank leakage diagnosis can be carried out on the oil tanks connected in series by utilizing the negative pressure detection method aiming at a single oil tank, other hardware does not need to be additionally added, the cost is reduced, the volume of the oil tank is large after the oil tanks are connected in series, and the capacity of pumping the negative pressure is enhanced due to the large volume of the oil tank when an engine idles, so that the detection speed is high.
Each oil tank is communicated through a pipeline, and a pipeline interface is positioned at the top of each oil tank. The fuel in each tank may be the same or different. In particular, when the automobile uses methanol as fuel, energy is saved, and exhaust emission of the engine can be greatly reduced, but the methanol is not easy to ignite. One solution is to use gasoline to ignite the methanol. So need set up the oil tank subassembly on the car: the oil tank assembly comprises a methanol oil tank and a gasoline oil tank which are connected in series. A methanol liquid level sensor is required to be arranged on the methanol oil tank, a gasoline liquid level sensor is arranged on the gasoline oil tank, and the liquid level of the corresponding oil tank can be read through the corresponding liquid level sensor.
The method is executed by a vehicle controller, as shown in fig. 1, fig. 1 is a schematic flow chart of steps of a fuel tank leakage diagnosis method provided by an embodiment of the invention, and the method comprises the following steps.
Step S100:
acquiring a reference liquid level of the oil tank assembly and a first leakage pressure corresponding to the reference liquid level, wherein the reference liquid level of the oil tank assembly comprises a first liquid level of each oil tank;
in this step, the first leakage pressure is an actual measurement value of the leakage pressure corresponding to the reference liquid level of the tank assembly, and the test condition of the actual measurement value is a normal operating condition of the tank, that is, the tank is in a non-leakage state.
Step S200:
acquiring the current liquid level of each oil tank;
in this step, the liquid level of the respective tank is acquired by the respective liquid level sensor.
Step S300:
determining a second leakage pressure of the tank assembly based on the first leakage pressure, the current liquid level and the first liquid level of each of the tanks;
in this step, the first leakage pressure is restored according to the current liquid level and the first liquid level of each oil tank, and a second leakage pressure of the oil tank assembly is obtained.
Step S400:
carrying out negative pressure equalization processing on the oil tank assembly;
in the step, the negative pressure behind the throttle valve when the engine idles is utilized to enable the oil tank assembly to be communicated with the pipeline behind the throttle valve, so that the balance between the negative pressure behind the throttle valve and the internal pressure of the oil tank assembly is realized.
Step S500:
acquiring the actual pressure of the oil tank assembly subjected to the negative pressure equalization treatment;
step S600:
and comparing the actual pressure of the oil tank assembly with the second leakage pressure to obtain an oil tank leakage diagnosis result of the oil tank assembly.
As shown in fig. 2, the tank leakage diagnosis system further includes a ventilation pipe 910, an activated carbon container 920, a first solenoid valve 930, a second solenoid valve 940, a pressure sensor and a liquid level sensor provided to each of the tanks, the oil tank assembly is connected to an engine intake manifold 950 via the ventilation pipe 910, the activated carbon container 920 is disposed in the ventilation pipe 910, the activated carbon container 920 comprises an air inlet end 921, an air outlet end 922 and a breathing hole 923, the inlet end 921 is connected to the tank assembly, the outlet end 922 is connected to the engine inlet manifold 950, the first solenoid valve 930 is disposed at the breathing port 923, the second solenoid valve 940 is disposed between the exhaust end 922 and the engine intake manifold 950, the pressure sensor is used for detecting the pressure of the oil tank assembly, and when the transmitter idles, a negative pressure is formed behind a throttle valve 960; as shown in fig. 3, in step S400, the method further includes the following steps:
Step S410:
controlling the second electromagnetic valve to change from a closed state to an open state so as to enable air to enter the engine intake manifold;
step S420:
controlling the first electromagnetic valve to change from an open state to a closed state so that the pressure of the plurality of oil tanks is equal to the pressure of the engine intake manifold;
step S430:
and controlling the second electromagnetic valve to be changed from an open state to a closed state so as to close the plurality of oil tanks and pipelines communicated with the plurality of oil tanks.
In an embodiment of the present invention, after performing negative pressure equalization processing on the oil tank assembly with the first leakage pressure being the reference liquid level under a certain condition, the negative pressure equalization processing is obtained after a preset time period is separated, where a duration of the preset time period is Δ t, and in step S500, the method further includes: and acquiring the actual pressure of the oil tank assembly at the interval of the preset time period delta t. Therefore, the first leakage pressure and the second leakage pressure are ensured to be obtained after the negative pressure equalization processing and in the same time period, and the reliability of the detection result is ensured.
As shown in figure 4 of the drawings,
in step S300, the method further includes the steps of:
step S310: calculating a first difference value between the current liquid level of each oil tank and the maximum liquid level corresponding to the oil tank,
In this step, the first difference value is a difference between a maximum liquid level corresponding to the oil tank and a current liquid level of the oil tank.
Step S320: calculating a second difference between the first liquid level of each of the tanks and the corresponding maximum liquid level of the tank,
in this step, the second difference is a difference between a maximum liquid level corresponding to the oil tank and the first liquid level of the oil tank.
Step S330: and calculating a ratio between the first difference and the second difference of each of the tanks, and taking the ratio as a pressure change ratio.
Step S340: calculating the ratio between the liquid surface area of each oil tank and the sum of the liquid surface areas of all the oil tanks, and taking the ratio as a weight coefficient,
step S350: calculating the product of the pressure change rate of each oil tank and the weight coefficient corresponding to the oil tank, recording the product as the current pressure change rate,
step S360: calculating the sum of the current pressure change ratios of all the oil tanks, and recording the sum as a system pressure change ratio;
in this step, the equation of state p of the ideal gas is calculatedrefVref＝mrefRT (l)，
The deviation delta is taken at the same time on both sides to obtain the formula delta prefVref+prsfΔVref＝ΔmrefRT (2)。
In equation (2), the change in gas volume due to fuel evaporation is ignored, i.e., Δ Vref is 0. Where ref is a reference value, Vref and Pref are associated with the first liquid level in step S300, and Pref is the same as the first leakage pressure in step S300. The change law of the gas volume of the real oil tank can be expressed by the formula (2) as well.
Formula (1) is divided by formula (2) to obtain
I.e. the rate of change of the system pressure at the current level of the tank is Vref/V times the fuel vapour volume of the tank assembly at the reference level.
When the oil tank is full, the volume V of fuel vapor is smaller, V is smaller than Vref, and the pressure change speed of the oil tank assembly is accelerated.
When the fuel tank is empty, the fuel vapor volume V is large, V is larger than Vref, and the pressure change speed of the fuel tank assembly is slow.
Step S370: calculating the product of the system pressure change ratio and the first leakage pressure to obtain a second leakage pressure.
In this step, the second leakage pressure is a product of Δ t and a value of a product of the system pressure change ratio and the first leakage pressure. Therefore, the influence of the oil tank liquid level and different oil tank liquid levels on the fuel volatilization rate is considered in the determination of the second leakage pressure, and the reliability of the oil tank leakage diagnosis result is ensured.
Further comprising in step S700:
if the actual pressure is smaller than the second leakage pressure, the oil tank leakage diagnosis result is no leakage; and if the actual pressure is greater than or equal to the second leakage pressure, the oil tank leakage diagnosis result is leakage. That is, when the tank pressure speed changes rapidly, the actual pressure is greater than or equal to the second leakage pressure, and the tank is considered to have a leakage.
In the embodiment of the application, in order to make the method for diagnosing the leakage of the oil tank reflect the actual condition better, the first leakage pressure comprises the upper limit of the first leakage pressure range and the lower limit of the first leakage pressure range, and the condition that the oil tank has no serious leakage and serious leakage in actual use is considered. When the oil tank has the condition of no serious leakage, the actual pressure is between the lower limit of the first leakage pressure range and the upper limit of the first leakage pressure range, and when the oil tank has the condition of serious leakage, the actual pressure exceeds the upper limit of the first leakage pressure range.
In an embodiment of the present application, the second leakage pressure comprises a second leakage pressure range upper limit and a second leakage pressure range lower limit. The second upper leakage pressure range limit and the second lower leakage pressure range limit are obtained by respectively correcting the first upper leakage pressure range limit and the first lower leakage pressure range limit, the second upper leakage pressure range limit and the second lower leakage pressure range limit are obtained by multiplying the system pressure change ratio by the first upper leakage pressure range limit and the first lower leakage pressure range limit, and the calculation method of the system pressure change ratio refers to steps S310 to S360.
As shown in fig. 5, a schematic diagram of the diagnosis results provided by the embodiment of the present invention includes point P1, point P2, point E3, point E2, point P1, point P, and point P, and point P, point P, point P, point P.
In an embodiment of the application, the step of comparing the actual pressure of the tank assembly with the second leakage pressure to obtain a tank leakage diagnosis result further includes: if the actual pressure is less than or equal to the lower limit of the second leakage pressure range, the oil tank leakage diagnosis result is no leakage; if the actual pressure is between the upper limit of the second leakage pressure range and the lower limit of the second leakage pressure range, the oil tank leakage diagnosis result is that the oil tank does not leak seriously; and if the actual pressure is greater than or equal to the upper limit of the second leakage pressure range, the oil tank leakage diagnosis result is serious leakage.
When the fuel tank is full, the volume V of the fuel vapor is smaller, V < Vref, the pressure change speed is accelerated, and the lower limit of the second leakage pressure range corresponding to the full fuel tank is E31, so E31> E3.
When the fuel tank is empty, the fuel vapor volume V is larger, V is larger than Vref, the pressure change speed is slow, the lower limit of the second leakage pressure range corresponding to the full fuel tank is E32, and E32< E3.
The connecting line of the intersection point of the P2 point and the time axis is the change curve of the tank pressure when the tank diagnosis result is serious leakage.
The embodiment of the application also discloses an oil tank leakage diagnosis system, which comprises an oil tank assembly and a vehicle control unit, wherein the oil tank assembly comprises a plurality of oil tanks connected in series; as shown in fig. 6, the vehicle control unit includes: a first obtaining module 810, a second obtaining module 820, a determining module 830, a processing module 840, a third obtaining module 850 and a comparing module 860; the first obtaining module 810 is configured to obtain a reference liquid level of the tank assembly and a first leakage pressure corresponding to the reference liquid level, where the reference liquid level of the tank assembly includes a first liquid level of each tank; the second obtaining module 820 is used for obtaining the current liquid level of each oil tank; the determining module 830 comprises determining a second leakage pressure of the tank assembly based on the first leakage pressure, the current liquid level of each of the tanks, and the first liquid level; the processing module 840 performs negative pressure equalization processing on the oil tank assembly; the third obtaining module 850 is configured to obtain the actual pressure of the fuel tank assembly after the negative pressure equalization processing; the comparing module 860 compares the actual pressure of the tank assembly with the second leakage pressure to obtain a tank leakage diagnosis result of the tank assembly. According to the invention, the plurality of oil tanks in the oil tank assembly are connected in series for diagnosis, the oil tanks are large in size after the plurality of oil tanks are connected in series, the negative pressure pumping capacity is strong after negative pressure equalization treatment, and the detection speed is high; the system is little changed, the cost is saved, meanwhile, the correction is carried out according to the liquid level of the oil tank, the influence of different oil tank liquid levels on the volatilization rate of the fuel oil is considered, the second leakage pressure serving as a diagnostic standard is determined according to the liquid level of the oil tank, and the reliability of the oil tank leakage diagnostic result is improved by connecting the diagnostic standard with the liquid level of the oil tank
Embodiments of the present application also disclose a vehicle configured with the tank leak diagnosis system as described above. The specific structure of the tank leakage diagnosis system is as described above, and will not be described herein.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
Claims (10)
1. A fuel tank leakage diagnosis method is characterized by being used for a fuel tank leakage diagnosis system, wherein the fuel tank leakage diagnosis system comprises a fuel tank assembly and a vehicle control unit, the fuel tank assembly comprises a plurality of fuel tanks which are connected in series;
the method is executed by a vehicle control unit and comprises the following steps:
acquiring a reference liquid level of the oil tank assembly and a first leakage pressure corresponding to the reference liquid level, wherein the reference liquid level of the oil tank assembly comprises a first liquid level of each oil tank;
acquiring the current liquid level of each oil tank,
determining a second leakage pressure of the tank assembly based on the first leakage pressure, the current liquid level and the first liquid level of each of the tanks;
carrying out negative pressure equalization processing on the oil tank assembly;
Acquiring the actual pressure of the oil tank assembly subjected to the negative pressure equalization treatment;
and comparing the actual pressure of the oil tank assembly with the second leakage pressure to obtain an oil tank leakage diagnosis result of the oil tank assembly.
2. The fuel tank leakage diagnosis method according to claim 1, wherein the fuel tank leakage diagnosis system further comprises a ventilation pipe, an activated carbon container, a first solenoid valve, a second solenoid valve, a pressure sensor and a liquid level sensor arranged in each fuel tank, the fuel tank assembly is connected with an engine intake manifold via the ventilation pipe, the activated carbon container is arranged in the ventilation pipe, the activated carbon container comprises an intake end, an exhaust end and a breathing port, the intake end is connected with the fuel tank assembly, the exhaust end is connected with the engine intake manifold, the first solenoid valve is arranged at the breathing port, the second solenoid valve is arranged between the exhaust end and the engine intake manifold, and the pressure sensor is used for detecting the pressure of the fuel tank assembly;
the negative pressure equalization processing of the oil tank assembly comprises the following steps:
controlling the second electromagnetic valve to change from a closed state to an open state so as to enable air to enter the engine intake manifold;
Controlling the first electromagnetic valve to change from an open state to a closed state so that the pressure of the plurality of oil tanks is equal to the pressure of the engine intake manifold;
and controlling the second electromagnetic valve to be changed from an open state to a closed state so as to close the plurality of oil tanks and pipelines communicated with the plurality of oil tanks.
3. The fuel tank leakage diagnosis method according to claim 1, wherein the first leakage pressure is obtained after a predetermined time interval after the fuel tank assembly with the reference level is subjected to negative pressure equalization processing under certain conditions,
in the step of obtaining the actual pressure of the fuel tank assembly after the negative pressure equalization processing, the method further includes:
and acquiring the actual pressure of the oil tank assembly at intervals of the preset time period.
4. A tank leak diagnostic method in accordance with claim 1, wherein said step of determining a second leak pressure of said tank assembly based on said first leak pressure, a current fluid level of each of said tanks, and a first fluid level, further comprises:
calculating a first difference value between the current liquid level of each oil tank and the maximum liquid level corresponding to the oil tank,
Calculating a second difference between the first liquid level of each of the tanks and the corresponding maximum liquid level of the tank,
calculating a ratio between the first difference and the second difference for each of the tanks, taking the ratio as a pressure change ratio,
calculating the ratio between the liquid surface area of each oil tank and the sum of the liquid surface areas of all the oil tanks, and taking the ratio as a weight coefficient,
calculating the product of the pressure change rate of each oil tank and the weight coefficient corresponding to the oil tank, recording the product as the current pressure change rate,
calculating the sum of the current pressure change ratios of all the oil tanks, and recording the sum as a system pressure change ratio;
calculating the product of the system pressure change ratio and the first leakage pressure to obtain a second leakage pressure.
5. A method as set forth in claim 1, wherein the step of comparing the actual pressure of the fuel tank assembly with the second leakage pressure to obtain the result of the tank leakage diagnosis further comprises:
if the actual pressure is smaller than the second leakage pressure, the oil tank leakage diagnosis result is no leakage; and if the actual pressure is greater than or equal to the second leakage pressure, the oil tank leakage diagnosis result is leakage.
6. A tank leak diagnostic method according to claim 1, wherein said first leak pressure comprises a first leak pressure range upper limit and a first leak pressure range lower limit.
7. The fuel tank leakage diagnostic method according to claim 6, wherein the second leakage pressure includes a second leakage pressure range upper limit and a second leakage pressure range lower limit.
8. The method according to claim 7, wherein the step of comparing the actual pressure of the tank assembly with the second leakage pressure to obtain the tank leakage diagnosis result further comprises:
if the actual pressure is less than or equal to the lower limit of the second leakage pressure range, the oil tank leakage diagnosis result is no leakage; if the actual pressure is between the upper limit of the second leakage pressure range and the lower limit of the second leakage pressure range, the oil tank leakage diagnosis result is that the oil tank does not leak seriously; and if the actual pressure is greater than or equal to the upper limit of the second leakage pressure range, the oil tank leakage diagnosis result is serious leakage.
9. The fuel tank leakage diagnosis system is characterized by comprising a fuel tank assembly and a vehicle control unit, wherein the fuel tank assembly comprises a plurality of fuel tanks which are connected in series;
The vehicle control unit comprises: the device comprises a first acquisition module, a second acquisition module, a determination module, a processing module, a third acquisition module and a comparison module;
the first acquisition module is used for acquiring a reference liquid level of the oil tank assembly and a first leakage pressure corresponding to the reference liquid level, wherein the reference liquid level of the oil tank assembly comprises the first liquid level of each oil tank;
the second acquisition module is used for acquiring the current liquid level of each oil tank;
the determining module comprises determining a second leakage pressure of the tank assembly based on the first leakage pressure, the current liquid level and the first liquid level of each of the tanks;
the processing module performs negative pressure equalization processing on the oil tank assembly;
the third acquisition module is used for acquiring the actual pressure of the oil tank assembly subjected to the negative pressure equalization treatment;
the comparison module compares the actual pressure of the oil tank assembly with the second leakage pressure to obtain an oil tank leakage diagnosis result of the oil tank assembly.
10. A vehicle provided with the tank leak diagnosis system according to claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010089931.9A CN111332228B (en) | 2020-02-13 | 2020-02-13 | Oil tank leakage diagnosis method and system and automobile |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010089931.9A CN111332228B (en) | 2020-02-13 | 2020-02-13 | Oil tank leakage diagnosis method and system and automobile |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111332228A CN111332228A (en) | 2020-06-26 |
| CN111332228B true CN111332228B (en) | 2021-10-26 |
Family
ID=71177742
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010089931.9A Active CN111332228B (en) | 2020-02-13 | 2020-02-13 | Oil tank leakage diagnosis method and system and automobile |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111332228B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
| CN114320637B (en) * | 2021-12-31 | 2023-03-21 | 中国第一汽车股份有限公司 | Fuel evaporation leakage detection method |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5573467B2 (en) * | 2010-08-04 | 2014-08-20 | トヨタ自動車株式会社 | Fuel supply system leak detection method and fuel supply system leak diagnosis device |
| CN106500933A (en) * | 2016-12-27 | 2017-03-15 | 上海汽车集团股份有限公司 | High pressure resistant fuel tank leakage diagnosing method |
| CN107152354A (en) * | 2017-06-09 | 2017-09-12 | 吉利汽车研究院（宁波）有限公司 | A kind of vehicle fuel vapo(u)rization system leak diagnostic apparatus and its diagnostic method |
| DE102016119647A1 (en) * | 2016-03-25 | 2017-09-28 | Hyundai Motor Company | Method and device for controlling a valve |
| JP6387077B2 (en) * | 2016-12-21 | 2018-09-05 | 本田技研工業株式会社 | Fuel tank system |
| CN109695525A (en) * | 2017-10-20 | 2019-04-30 | 本田技研工业株式会社 | The apparatus for diagnosis of abnormality of fuel residual amount estimating device and fuel vapo(u)r closed system |
| CN110318898A (en) * | 2018-03-30 | 2019-10-11 | 联合汽车电子有限公司 | Leak diagnostic apparatus and method |
| CN110778406A (en) * | 2018-07-30 | 2020-02-11 | 罗伯特·博世有限公司 | Method for predicting failure of fuel injector of vehicle |
| CN111350598A (en) * | 2020-02-21 | 2020-06-30 | 吉利汽车研究院（宁波）有限公司 | Dual-fuel leakage diagnosis system and diagnosis method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10077731B2 (en) * | 2015-05-22 | 2018-09-18 | Ford Global Technologies, Llc | Method for detecting fuel system degradation |
-
2020
- 2020-02-13 CN CN202010089931.9A patent/CN111332228B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5573467B2 (en) * | 2010-08-04 | 2014-08-20 | トヨタ自動車株式会社 | Fuel supply system leak detection method and fuel supply system leak diagnosis device |
| DE102016119647A1 (en) * | 2016-03-25 | 2017-09-28 | Hyundai Motor Company | Method and device for controlling a valve |
| JP6387077B2 (en) * | 2016-12-21 | 2018-09-05 | 本田技研工業株式会社 | Fuel tank system |
| CN106500933A (en) * | 2016-12-27 | 2017-03-15 | 上海汽车集团股份有限公司 | High pressure resistant fuel tank leakage diagnosing method |
| CN107152354A (en) * | 2017-06-09 | 2017-09-12 | 吉利汽车研究院（宁波）有限公司 | A kind of vehicle fuel vapo(u)rization system leak diagnostic apparatus and its diagnostic method |
| CN109695525A (en) * | 2017-10-20 | 2019-04-30 | 本田技研工业株式会社 | The apparatus for diagnosis of abnormality of fuel residual amount estimating device and fuel vapo(u)r closed system |
| CN110318898A (en) * | 2018-03-30 | 2019-10-11 | 联合汽车电子有限公司 | Leak diagnostic apparatus and method |
| CN110778406A (en) * | 2018-07-30 | 2020-02-11 | 罗伯特·博世有限公司 | Method for predicting failure of fuel injector of vehicle |
| CN111350598A (en) * | 2020-02-21 | 2020-06-30 | 吉利汽车研究院（宁波）有限公司 | Dual-fuel leakage diagnosis system and diagnosis method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 本田思域CITY轿车汽油蒸汽泄漏诊断;黄林火;《技师手记AUTOMOBILE MAINTEANCE》;20160801;39 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111332228A (en) | 2020-06-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107420230B (en) | Carbon tank high-load desorption pipeline desorption flow diagnosis method | |
| CN111946477B (en) | Method for monitoring leakage of carbon tank cleaning electromagnetic valve | |
| CN110006607B (en) | System and method for detecting leakage of fuel evaporation system | |
| CN110230547B (en) | Vehicle-mounted fuel leakage detection method and detection system thereof | |
| CN101285436B (en) | System for detecting purge valve malfunction | |
| US6971375B2 (en) | Fuel vapor treatment system for internal combustion engine | |
| JP3116556B2 (en) | Airtightness check device for fuel tank system of internal combustion engine | |
| US6220229B1 (en) | Apparatus for detecting evaporative emission control system leak | |
| CN109113897A (en) | A kind of vehicle fuel evaporation leak diagnostic apparatus and its diagnostic method | |
| KR100307107B1 (en) | Apparatus and method for testing the performance of tank ventilation system | |
| US8984934B2 (en) | Method and system to validate a fuel level indicator in a vehicle | |
| CN111332228B (en) | Oil tank leakage diagnosis method and system and automobile | |
| CN114215664B (en) | Method and system for diagnosing leakage of evaporation system for fuel vehicle | |
| CN110031160A (en) | Fuel evaporation leak detection system and method | |
| CN112228217B (en) | Vehicle-mounted diagnosis device and diagnosis method for monitoring automobile fuel evaporation leakage | |
| JPH10170384A (en) | Method for measuring filling level of tank system | |
| JP4021957B2 (en) | Method for detecting refueling process in container | |
| US6886399B2 (en) | Method for determining mass flows into the inlet manifold of an internal combustion engine | |
| US20010049958A1 (en) | Leakage determination system for evaporative fuel processing system | |
| CN113237616A (en) | Combined detection system and method for leakage of automobile fuel evaporation system | |
| US11118958B2 (en) | System for determining a filling level in a fuel tank | |
| CN101598634B (en) | Wind condition based vapor leak detection test control system and method | |
| CN210834551U (en) | Device for testing original hydrocarbon discharge amount of automobile oil tank refueling and device for verifying adsorption capacity of activated carbon canister | |
| CN116220965A (en) | System and method for detecting leakage of fuel evaporation system | |
| CN114934853A (en) | Fuel leakage diagnosis method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |