KR102322386B1 - Fuel tank explosion prevention system - Google Patents

Abstract

The present invention relates to an apparatus for preventing explosion of a fuel tank of a vehicle fuel system, and more particularly, by removing in advance the combustibles (fuel evaporation gas), which is one of the conditions of combustion, when the explosive condition of a fuel tank that can occur at a low temperature is satisfied. An object of the present invention is to provide a fuel tank explosion prevention device for an automobile fuel system that prevents explosion of the fuel tank due to static electricity generated due to friction in a process in which the fuel in the fuel tank is pumped to the engine.

Description

Fuel tank explosion prevention system of automobile fuel system

The present invention relates to an apparatus for preventing explosion of a fuel tank of a vehicle fuel system, and more particularly, to an apparatus for preventing explosion of a fuel tank that may occur in a low temperature state.

The fuel system of an automobile consists of a fuel tank that stores fuel, a fuel pump that sucks/pressurizes the fuel stored in the fuel tank and supplies it to the engine, and a fuel filter that removes foreign substances from the fuel supplied to the engine.

In general, the fuel pump and the fuel filter are integrally configured, and the fuel sucked from the fuel pump is pressurized to the engine while passing through the fuel filter.

At this time, while the fuel is sucked from the fuel pump and passes through the fuel filter, static electricity is generated due to friction between the fuel pump and the case/filter paper of the fuel filter and the fuel, and is accumulated in parts such as the fuel pump and the fuel filter.

In other words, while the fuel is sucked in from the fuel pump and passes through the fuel filter, flowing charging occurs, the fuel is positively charged, and the case and the filter paper are negatively charged, thereby generating static electricity.

Static electricity generated in this way is excessively generated at a low temperature of -30°C or lower and accumulates in parts such as fuel pumps and fuel filters. There is a big problem with explosions.

Explosion of the fuel tank not only threatens the safety of the driver and passengers, but also causes deformation of the fuel tank and vehicle body, and burning of the fuel pump, resulting in excessive repair costs.

Patent Publication No. 10-2011-0045416

The present invention has been devised in view of the above points, and when the explosive condition of the fuel tank that can occur in a low temperature state is satisfied, the fuel in the fuel tank is converted into the engine by removing in advance flammables (fuel evaporation gas), which is one of the conditions of combustion. An object of the present invention is to provide a fuel tank explosion prevention device for an automobile fuel system that prevents explosion of the fuel tank due to static electricity generated due to friction in the process of being pumped to a fuel cell.

Accordingly, in the present invention, the BOG sensor for measuring the BOG concentration of the fuel tank; an outside temperature sensor for measuring the outside temperature of the vehicle; a purge valve for supplying the evaporated fuel gas of the canister collected from the fuel tank to the engine; It is determined whether the fuel tank can be exploded based on the measured values of the BOG sensor and the outside air temperature sensor, and when the fuel tank explosion is predicted, the BOG sensor measurement value is outside the set concentration range in which combustion is possible. and a controller that operates the purge valve to supply evaporated fuel to the engine.

According to an embodiment of the present invention, when the measured value of the BOG sensor is out of the set concentration range due to the operation of the purge valve, the controller stops supplying the BOG to the engine through the operation of the purge valve. and monitor the measured values of the outdoor temperature sensor and the boil-off gas sensor to determine whether the purge valve is re-operated.

Specifically, when the measured value of the outdoor temperature sensor is maintained below the reference temperature and the measured value of the BOG sensor re-enters the set concentration range, the controller restarts the purge valve to re-supply the BOG to the engine.

Preferably, when an explosion of the fuel tank is predicted, the controller closes the canister close valve further installed in the air line of the canister to block the inflow of external air into the canister.

In addition, in the present invention, the outdoor temperature sensor for measuring the vehicle external temperature; a purge valve for supplying the evaporated fuel gas of the canister collected from the fuel tank to the engine; When the measured value of the outside air temperature sensor is below a reference temperature set as a temperature at which excessive static electricity is generated in the fuel pump module, a controller operates the purge valve to supply the fuel vapor to the engine; The system's fuel tank explosion protection is also provided.

According to an embodiment of the present invention, the controller calculates the target oil vapor removal amount when the measured value of the outdoor temperature sensor is less than or equal to the reference temperature, and the amount of fuel vapor supplied to the engine through the purge valve is equal to the oil vapor removal target amount. When it arrives, the operation of the purge valve is stopped, and whether the purge valve is re-operated is determined according to the air-fuel ratio calculated based on the total capacity of the fuel tank, the amount of residual fuel, and the measured value of the outdoor temperature sensor.

In addition, according to another embodiment of the present invention, the controller calculates the target oil vapor removal amount when the measured value of the outdoor temperature sensor is below the reference temperature, and determines the amount of fuel vapor supplied to the engine through the purge valve to determine the oil vapor removal target amount. When reached, the operation of the purge valve is temporarily stopped for the set reference time.

Here, the target amount of oil vapor removal is calculated as "(total capacity of fuel tank - remaining fuel amount of fuel tank) * a ",

The air-fuel ratio is calculated as "predicted fuel evaporative gas generation according to external temperature change (Mf)/air mass according to outdoor temperature (Ma)", and the predicted fuel evaporative gas generation amount (Mf) is "[b * exp(c*)" Vp) * {exp(d*T2) - exp(e*T1)}] * Calculated as "remaining fuel in fuel tank", where

Wherein Vp is the fuel boil-off gas pressure, T1 is the outside air temperature when the operation of the purge valve is stopped, and T2 is the outside temperature (°C) before the operation is restarted after the operation of the purge valve is stopped, the a, b, c, d and e are proportional constants.

Preferably, when the measured value of the outside air temperature sensor is below the reference temperature, the controller closes the canister close valve further installed in the air line of the canister before operating the purge valve to block outside air from flowing into the canister.

According to the fuel tank explosion prevention device for a vehicle fuel system according to the present invention, the purge valve is operated when the fuel tank explosion condition is satisfied due to static electricity generated due to friction while the fuel in the fuel tank is pumped to the engine. By opening the purge line between the canister and the engine to release the fuel evaporative gas to the engine, it is possible to prevent combustion and explosion according to the concentration of fuel evaporative gas in the fuel tank in advance. It is possible to avoid the cost of car body repair, etc.

1 is a view showing a vehicle fuel system to which a fuel tank explosion prevention device according to a first embodiment of the present invention is applied;
2 is a schematic view showing a fuel tank explosion prevention method using the fuel tank explosion prevention device according to the first embodiment of the present invention;
3 is a schematic diagram showing a situation in which the fuel boil-off gas is forcibly purged by the fuel tank explosion prevention device according to the first embodiment of the present invention;
4 is a schematic diagram showing a fuel tank explosion prevention process using the fuel tank explosion prevention device according to the first embodiment of the present invention;
5 is a view showing a vehicle fuel system to which the fuel tank explosion prevention device according to the second embodiment of the present invention is applied;
6 is a schematic diagram showing a fuel tank explosion prevention method using a fuel tank explosion prevention device according to a second embodiment of the present invention;
7 is a schematic diagram showing a situation in which the fuel evaporation gas is forcibly purged by the fuel tank explosion prevention device according to the second embodiment of the present invention;
8 is a schematic diagram showing a fuel tank explosion prevention process using the fuel tank explosion prevention device according to the second embodiment of the present invention;

Hereinafter, the present invention will be described so that those skilled in the art can easily practice it.

As shown in FIG. 1 , the vehicle fuel system of the present invention includes a fuel tank 10 for storing fuel, a fuel pump that sucks/pressurizes the fuel stored in the fuel tank 10 and supplies it to the engine, and the fuel supplied to the engine. It is configured to include a fuel pump module 20 made of a fuel filter for removing foreign substances, and a canister 30 for collecting fuel vapor generated from the fuel tank 10 .

The canister 30 collects the boil-off gas discharged from the fuel tank 10 through the boil-off gas line 12 connected between the fuel tank 10 and the canister 30, and the purge valve 34 is opened. When the engine negative pressure is transferred to the canister 30, the collected fuel evaporation gas is transferred to the outside air and supplied to the engine.

The purge valve 34 is a normally closed valve, which is installed in the purge line 32 connected between the intake manifold 60 and the canister 30 of the engine, and periodically opens the purge line 32 during the purge operation. When not in operation, the purge line 32 is closed.

In addition, an air line 36 is connected to the canister 30 to allow air inflow from the atmosphere, and a canister close valve (CCV) 38 is installed in the air line 36 as a normally open valve. .

The canister closing valve 38 closes the air line 36 during the closing operation to block the inflow of external air into the canister 30, and normally, the fuel system to close the air line 36 during self-diagnosis of the vehicle. It is selectively used for, and maintains the air line 36 in an open state when not in operation.

In addition, the fuel tank 10 has a fuel amount sensor 16 capable of measuring the amount of fuel remaining in the fuel tank 10 , and a fuel tank pressure sensor capable of measuring the fuel vapor pressure inside the fuel tank 10 . A (FTPS) 18 is installed, and the measured value of the fuel amount sensor 16 is displayed through a cluster in the vehicle interior.

As the controller (ECU) 50, one of the controllers already installed in the vehicle is used, and controls the operation of the purge valve 34 and the canister close valve 38, and the fuel amount sensor 16 and the fuel tank pressure sensor. (18) receives the measured value, etc.

In addition, the controller 50 also receives the measurement values of the intake air pressure sensor (MAP sensor) 62 for measuring the intake air pressure of the intake manifold 60 and the outdoor air temperature sensor 40 for measuring the vehicle external temperature, The measured value of the BOG sensor 14 installed in the BOG line 12 to measure the concentration of BOG is also received.

The BOG sensor 14 is additionally mounted to the fuel system in order to prevent the explosion of the fuel tank 10 due to static electricity, and evaporates fuel generated in the fuel tank 10 and discharged to the BOG line 12 . It is installed in the boil-off gas line 12 to measure the concentration of gas, for example, a HC sensor (Hydrocarbon Sensor) is used.

For reference, the outdoor temperature sensor 40 can be used to be used for controlling the air conditioner, etc., and the unexplained reference numeral 39 denotes an air filter 39 for removing foreign substances from the air flowing into the canister 30 . )am.

Here, an apparatus for preventing explosion of a fuel tank of a fuel system according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 4 .

The fuel tank explosion prevention device determines whether the explosive condition of the fuel tank 10 is satisfied by using a concentration measurement value of the fuel evaporation gas generated inside the fuel tank 10 , and determines that the condition is satisfied By supplying (purging) the fuel evaporator to the engine, it is possible to prevent the explosion of the fuel tank 10 in advance by removing flammable substances (fuel evaporative gas), which is one of the conditions of combustion, and for this purpose, it is configured as shown in FIG. The boil-off gas sensor 14, the outside air temperature sensor 40, the purge valve 34, and the controller 50 of the fuel system are configured or further include a canister close valve 38.

As shown in FIGS. 2 and 4 , first, the controller 50 determines whether the explosive condition of the fuel tank 10 is satisfied based on the measured values received from the boil-off gas sensor 14 and the outdoor temperature sensor 40 . judge

Static electricity generated while the fuel is pumped from the fuel pump module 20 to the engine is excessively generated at a low temperature of -30°C or less and is accumulated in the fuel pump module 20, etc., and the accumulated static electricity is stored in the fuel tank 10 When the fuel tank 10 is discharged as "oil vapor (fuel evaporative gas)" in a combustible concentration range, the evaporative gas sensor 14 ) and the measured value of the outdoor temperature sensor 40 is monitored.

Specifically, the controller 50 determines the condition that the measured value of the BOG sensor 14 enters the set concentration range (minimum concentration value ~ maximum concentration value) in which combustion is possible, and the measured value of the outdoor temperature sensor 40 is When all of the conditions below the reference temperature set as the relatively excessive generation of static electricity generated in the fuel pump module 20 are satisfied, it is determined that the explosion of the fuel tank 10 is possible.

In addition, in the case of static electricity, it is excessively generated at a low temperature below -30 ℃, but it is possible to set the reference temperature as a temperature value higher than -30 ℃ in consideration of the safety factor. Combustion is possible, but it is also possible to set the set concentration range as 1 to 7% in consideration of the safety factor.

On the other hand, the condition in which the measured value of the BOG sensor 14 is outside the set concentration range (minimum concentration value ~ maximum concentration value) in which combustion is possible, that is, the setting in which the measured value of the BOG sensor 14 is capable of combustion When both the condition of being less than the minimum concentration value of the concentration range and the condition in which the measured value of the outdoor temperature sensor 40 exceeds the reference temperature set as excessive generation of static electricity generated in the fuel pump module 20, the fuel It is determined that the possibility of explosion of the tank 10 is eliminated.

Accordingly, the controller 50 enters the fuel system into an explosion prevention control mode, that is, a forced purge execution mode, when all of the explosive conditions of the fuel tank 10 are satisfied and the occurrence of an explosion is predicted, and the boil-off gas sensor 14 . The purge valve 34 is operated until the measured value of is out of the set concentration range where combustion is possible, so that the fuel boil-off gas collected from the canister 30 is supplied to the intake manifold 60 of the engine (refer to FIG. 3 ). ).

When the fuel system enters the forced purge mode, the controller 50 forcibly operates the purge valve 34 to open, even if the normal purge execution condition is not satisfied, so that the evaporated fuel gas collected in the canister 30 is removed. to be supplied to the engine.

Typical conditions for performing purging include the amount of fuel remaining in the fuel tank, vehicle speed, intake pressure of the intake manifold, and concentration of the fuel evaporated gas collected in the canister.

In the case of a fuel system provided with the canister close valve 38 , before the purge valve 34 is opened, the canister close valve 38 is operated to close the canister 30 to block the inflow of external air into the fuel system. It is desirable to increase the removal efficiency of boil-off gas.

The controller 50 monitors the measured value of the boil-off gas sensor 14 in real time and controls the operation of the purge valve 34, and the measured value of the boil-off gas sensor 14 is out of the set concentration range, and combustion/explosion is impossible. The purge operation is continued by controlling the opening of the purge valve 34 until the concentration is reached.

Thereafter, when it is determined that the measured value of the BOG sensor 14 is out of the set concentration range but the vehicle outside temperature is below the reference temperature, the controller 50 releases the BOG to the engine through the open operation of the purge valve 34 . Temporarily stop supply. In other words, if the measured value of the BOG sensor 14 is less than or greater than the maximum concentration value of the set concentration range, and the vehicle outside air temperature is below the reference temperature, Temporarily stops the purge operation mode of the purge valve 34 that discharges to the .

When the measured value of the BOG sensor 14 is out of the set concentration range, the controller 50 temporarily suspends the operation of the purge valve 34 based on the vehicle outside temperature or releases the forced purge execution mode. Specifically, when the outdoor temperature is below the reference temperature, the operation of the purge valve 34 is temporarily stopped, and when the outdoor temperature exceeds the reference temperature, the forced purge execution mode is released.

When the measured value of the boil-off gas sensor 14 re-enters the set temperature range in a state in which the operation of the purge valve 34 is temporarily stopped, the purge valve 34 is operated again to resume the purge operation of discharging the fuel boil-off gas to the engine. Conduct.

In other words, in a state in which the purge operation is temporarily stopped, the measured values of the outdoor temperature sensor 40 and the BOG sensor 14 are monitored in real time, and as a result of the monitoring, when the outside air temperature is below the reference temperature, the BOG sensor 14 When the measured value of is re-entered the set temperature range, the purge valve 34 is opened again to re-supply the boil-off gas to the engine.

This series of processes may be shown as shown in FIG. 4, but is not limited thereto, and for example, the step of temporarily stopping the purge operation and the step of re-executing the purge operation may be repeated several times until the forced purge mode is released. .

However, if the BOG sensor 14 is additionally used like the fuel tank explosion prevention device according to the first embodiment, a corresponding cost is incurred, so without adding parts such as the BOG sensor 14 to the fuel system. An apparatus for preventing explosion of a fuel tank according to a second possible embodiment will be described with reference to FIGS. 5 to 8 .

5, the fuel system employing the fuel tank explosion prevention device according to the second embodiment of the present invention includes the BOG sensor 14 in the fuel system adopting the fuel tank explosion prevention device according to the first embodiment. Except for the deletion, the hardware is identically configured.

The fuel tank explosion prevention device according to the second embodiment of the present invention determines whether a condition for excessive generation/accumulation of static electricity of the fuel pump module 20 is satisfied based on the vehicle outside temperature, and when it is determined that the condition is satisfied By supplying the fuel boil-off gas to the engine, it is possible to prevent the explosion of the fuel tank 10 in advance by removing combustibles (fuel evaporation gas), which is one of the conditions of combustion, and for this purpose, the fuel system configured as shown in FIG. It is composed of the outdoor temperature sensor 40 and the purge valve 34 , the fuel amount sensor 16 , and the controller 50 , or further includes a canister close valve 38 .

6 and 8 , first, the controller 50 determines whether the explosive condition of the fuel tank 10 is satisfied based on the measurement value received from the outdoor temperature sensor 40 .

Specifically, if the measured value of the outdoor temperature sensor 40 is below the reference temperature set as the temperature at which excessive static electricity occurs, the controller 50 determines that the explosive condition of the fuel tank 10 is satisfied, and sets the reference temperature. If it exceeds, the explosive condition of the fuel tank 10 is not satisfied and it is determined that there is no possibility of explosion.

The reference temperature is set as a temperature at which static electricity generated due to flow charging according to the flow of fuel in the fuel pump module 20 is excessively generated.

The controller 50 monitors the measured value of the outdoor temperature sensor 40 in real time and when the explosive condition is satisfied and the explosion possibility/occurrence is predicted, the fuel system enters the forced purge mode, and the fuel system and the fuel The amount of BOG to be removed from the tank 10 (ie, the target amount of oil vapor removal) is calculated, and the amount of BOG supplied to the engine through the purge line 32 (ie, the amount of purge) is the amount of the oil vapor removed. The purge valve 34 is forcibly opened until the target amount is reached (refer to FIG. 7).

When the fuel system enters the forced purge execution mode, even if the normal purging operation conditions are not satisfied, that is, regardless of conditions such as the amount of BOG loaded in the canister 30 and the concentration of BOG collected in the canister , by forcibly operating the purge valve 34 to open so that the evaporated fuel gas collected in the canister 30 is supplied to the engine.

And, in the case of the fuel system provided with the canister close valve 38, before the purge valve 34 is opened, the canister close valve 38 is operated to close the air line 36 to the canister 30 through the air line 36. By blocking the inflow of outside air, the removal efficiency of fuel evaporative gas in the fuel system is increased.

Thereafter, the controller 50 operates the purge valve 34 open when it is determined that the purge amount of the fuel evaporation gas supplied to the engine through the purge valve 34 reaches the oil vapor removal target amount but the vehicle outside air temperature is below the reference temperature. is temporarily stopped, and the condition for purging and re-supplying fuel evaporative gas through the re-operation of the purge valve 34 based on the amount of evaporative gas generated (Mf) and the air mass (Ma) in the fuel tank according to the change of the outside temperature It is determined whether this is satisfied.

Specifically, the controller 50 determines the outside air temperature based on the total capacity (system characteristic value) of the fuel tank 10, the remaining fuel amount (measured value of the fuel amount sensor), and the vehicle outside air temperature (measured value of the outside air temperature sensor) of the fuel tank 10 . Calculated by predicting/estimating the generation amount (Mf) of the fuel boil-off gas generated in the fuel tank 10 according to the change, calculating the air mass (Ma) according to the real-time temperature, and calculating the predicted amount of the fuel evaporation gas ( That is, it is determined whether or not to restart the purge valve 34 that has stopped operating based on the predicted generation amount of the fuel boil-off gas) (Mf) and the air mass (Ma).

At this time, the air-fuel ratio (AF=Mf/Ma) is calculated as a value obtained by dividing the predicted generation amount of the fuel boil-off gas (Mf) by the air mass (Ma), and the reference air-fuel ratio at which the air-fuel ratio (AF=Mf/Ma) is set When it becomes less than, the purge valve 34 is operated again, and when the air-fuel ratio exceeds the reference air-fuel ratio, the operation stop state of the purge valve 34 is continued.

As another simpler control method, when the purge amount of the fuel evaporation gas supplied to the engine through the purge valve 34 reaches the oil vapor removal target amount, the controller 50 controls the open operation of the purge valve 34 for a set reference time. After temporarily stopping, when the reference time elapses, the purge valve 34 is forcibly re-operated to supply the boil-off gas to the engine.

In this case, the purge valve 34 is re-operated at regular time intervals (periodically) according to the reference time, and the re-operation of the purge valve 34 by this close-loop control method is the vehicle outside temperature. is repeated until the forced purge mode is canceled by exceeding the reference temperature.

To this end, the controller 50 monitors the measured value of the outdoor temperature sensor 40 in real time while the fuel system enters the forced purge execution mode, and when the vehicle exterior temperature exceeds the reference temperature, the forced purging execution mode release

In addition, the reference time may be set as an appropriate value according to the characteristics of the fuel system as a time for temporarily stopping the operation of the purge valve 34 .

On the other hand, the target oil vapor removal amount (ℓ) is calculated as "(total capacity of fuel tank - remaining fuel amount of fuel tank) * a ", where a is the fuel system characteristic (total capacity of fuel tank, presence or absence of canister close valve) etc.) is a proportional constant set according to

At this time, the minimum oil vapor removal target amount is calculated as "total capacity of fuel tank - amount of remaining fuel in fuel tank".

The value of the proportional constant varies depending on the total capacity of the fuel tank 10 and the presence or absence of the canister closing valve 38 of the target oil vapor removal amount. For example, if a is 1.0 for a fuel system in which the canister close valve 38 is not installed, a may be set to 5.0 in the case of a fuel system in which the canister close valve 38 is installed.

This means that in the case of a fuel system in which the canister 30 is always connected to the atmosphere because the canister closing valve 38 is not installed in the air line 36, external air is prevented from flowing into the canister 30 during the forced purge of the fuel boil-off gas. Since it cannot be shut off, the external air and fuel evaporative gas are mixed at a certain ratio and supplied to the engine side, so that the canister 30 is purged from the canister 30 to the engine compared to the case of blocking the inflow of external air using the canister close valve 38 This is because the proportional constant value is set in consideration of the decrease in the concentration of the fuel boil-off gas.

Next, the method of calculating the air-fuel ratio described above will be further described.

The predicted amount of evaporative gas (Mf) generated according to the change in the outside temperature can be calculated as in Equation 1 below.

Equation 1: Estimated amount of fuel evaporative gas generated (Mf) according to change in outside temperature (Mf) =

Fuel evaporative gas generation in fuel tank (m) * Remaining fuel in fuel tank

In addition, the amount of evaporative gas (m) generated per unit volume in the fuel tank 10 can be calculated as shown in Equation 2 below.

Equation 2: Amount of evaporative gas generated in fuel tank (m, g/ℓ) =

b * exp(c*Vp) * {exp(d*T2) - exp(e*T1)}

Here, the Vp is the fuel boil-off gas pressure, the T1 is the vehicle outside temperature (°C) at the time when the purge valve 34 is stopped, and the T2 is the real time until the purge valve 34 is restarted after the operation is stopped. is the vehicle outside temperature (°C) measured as , and b, c, d, and e are proportional constants set according to the characteristics of the fuel system.

The Vp is a bad condition, and a constant value set based on a high RVP (Reid Vapor Pressure) is used, and the T2 is a set value (α) added to the outdoor temperature measured in real time in consideration of the safety factor due to the influence of the vehicle muffler. It can be applied as the summed temperature value.

And, the real-time air mass Ma according to the vehicle outside temperature can be calculated as shown in Equation 3 below.

Equation 3: Air mass (Ma) = Real-time air density according to vehicle outside temperature * Gas capacity of fuel tank

Here, the gas capacity of the fuel tank 10 is calculated as a value obtained by subtracting the remaining fuel amount of the fuel tank 10 from the total capacity of the fuel tank 10 .

The air-fuel ratio (AF=Mf/Ma) is calculated as a value obtained by dividing the predicted fuel evaporation gas generation amount (Mf) by the air mass (Ma), and the purge valve 34 ) to determine whether it works again.

When the re-operation of the purge valve 34 is determined according to the air-fuel ratio (AF) calculated as above, the operation stop time of the purge valve 34 is changed according to the air-fuel ratio (AF) that changes in real time.

The fuel tank explosion prevention device according to the second embodiment of the present invention can be implemented only with the parts already provided in the vehicle without adding additional parts, and thus has the advantage that there is no cost incurred due to the addition of parts, and also the existing fuel system It is possible to reduce the cost of preventing consumer complaints because only the software of the controller needs to be updated without replacing parts of the controller.

In addition, the fuel tank explosion prevention device according to the first and second embodiments of the present invention has an advantage of high stability because it prevents the explosion of the fuel tank in advance by a feed-forward control method.

As the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited to the above-described embodiments, and various modifications and Improvements are also included in the scope of the present invention.

10: fuel tank
12: boil-off gas line
14: boil-off gas sensor
16: fuel level sensor
18: fuel tank pressure sensor
20: fuel pump module
30 : canister
32: purge line
34: purge valve
36: Airline
38: canister close valve
40: outdoor temperature sensor
50: controller
60: intake manifold

Claims (10)

BOG sensor for measuring the BOG concentration of the fuel tank;
an outside temperature sensor for measuring the outside temperature of the vehicle;
a purge valve for supplying the evaporated fuel gas of the canister collected from the fuel tank to the engine;
It is determined whether the fuel tank can be exploded based on the measured values of the BOG sensor and the outside air temperature sensor, and when the fuel tank explosion is predicted, the BOG sensor measurement value is outside the set concentration range in which combustion is possible. a controller that operates the purge valve to supply the boil-off gas to the engine;
A fuel tank explosion prevention device of a vehicle fuel system, comprising a.
The method according to claim 1,
When the measured value of the BOG sensor is out of the set concentration range due to the operation of the purge valve, the controller stops supplying the BOG to the engine through the operation of the purge valve, and the outdoor temperature sensor and BOG sensor A device for preventing explosion of a fuel tank of a vehicle fuel system, characterized in that it is determined whether the purge valve is re-operated by monitoring the measured value of .
3. The method according to claim 2,
When the measured value of the outdoor temperature sensor is maintained below the reference temperature and the measured value of the BOG sensor re-enters the set concentration range, the controller restarts the purge valve to re-supply the BOG to the engine. Fuel tank explosion protection device in automobile fuel system.
The method according to claim 1,
Wherein the controller closes the canister close valve further installed in the air line of the canister when the fuel tank is predicted to explode to block the inflow of external air into the canister.
an outside temperature sensor for measuring the outside temperature of the vehicle;
a purge valve for supplying the evaporated fuel gas of the canister collected from the fuel tank to the engine;
a controller that operates the purge valve to supply evaporated fuel to the engine when the measured value of the outdoor temperature sensor is below a reference temperature set as a temperature at which excessive static electricity is generated in the fuel pump module;
A fuel tank explosion prevention device of a vehicle fuel system, comprising a.
6. The method of claim 5,
The controller calculates the target oil vapor removal amount when the measured value of the outdoor temperature sensor is below the reference temperature, and stops the operation of the purge valve when the amount of fuel vapor supplied to the engine through the purge valve reaches the oil vapor removal target amount , A fuel tank explosion prevention device for a vehicle fuel system, characterized in that it is determined whether the purge valve is re-operated according to the air-fuel ratio calculated based on the total capacity of the fuel tank, the amount of residual fuel, and the measurement value of the outdoor temperature sensor.
6. The method of claim 5,
The controller calculates the target oil vapor removal amount when the measured value of the outdoor temperature sensor is below the reference temperature, and sets the operation of the purge valve when the amount of fuel vapor supplied to the engine through the purge valve reaches the oil vapor removal target amount A fuel tank explosion prevention device for an automobile fuel system, characterized in that it is temporarily stopped for a period of time.
8. The method according to claim 6 or 7,
The target amount of oil vapor removal is calculated as "(total capacity of fuel tank - amount of remaining fuel in fuel tank) * a ", wherein a is a proportional constant.
7. The method of claim 6,
The air-fuel ratio is "predicted fuel evaporative gas generation according to external temperature change (Mf)/air mass according to outdoor temperature (Ma)", and the fuel evaporative gas predicted generation amount (Mf) is "[b * exp (c * Vp) * {exp(d*T2) - exp(e*T1)}] * Remaining fuel in fuel tank",
Wherein Vp is the fuel boil-off gas pressure, T1 is the outside air temperature at the time when the operation of the purge valve is stopped, and T2 is the outside temperature (°C) before the operation is restarted after the operation of the purge valve is stopped, and b, c, d, e is a proportional constant, the fuel tank explosion prevention device of the vehicle fuel system.
6. The method of claim 5,
When the measured value of the outdoor temperature sensor is below the reference temperature, the controller closes the canister close valve further installed in the air line of the canister before operating the purge valve to block outside air from flowing into the canister. The system's fuel tank explosion protection device.

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