KR102115166B1 - Apparatus and system for supplying dimethyl ether fuel - Google Patents

Abstract

One embodiment provides an apparatus for supplying fuel, including: a feed pump that receives DME fuel from a dimethyl ether (DME) storage tank through a fuel supply pipe, supplies the DME fuel to a DME injection device, and controls revolution of a drive motor according to the output of an engine; a first temperature sensor for measuring the temperature of the feed pump; a first cooling fan for controlling output according to the measured value of the first temperature sensor, as a fan for cooling the feed pump; and a second cooling fan mounted on a fuel recovery pipe for recovering the remaining DME and cooling the fuel recovery pipe.

Description

Dimethyl ether fuel supply device and fuel supply system {APPARATUS AND SYSTEM FOR SUPPLYING DIMETHYL ETHER FUEL}

This embodiment relates to a DME fuel supply system for supplying dimethyl ether (Dimethyl ether, hereinafter referred to as DME) existing in the gaseous state in the atmosphere by replacing diesel oil with an existing diesel engine.

Diesel engines have the advantages of higher power, higher efficiency, and less carbon dioxide emissions than gasoline engines, but because there are problems of exhausting large amounts of air pollutants such as soot, diesel (light oil) can be replaced as a method to solve them. The production and distribution of alternative fuels has been attempted, and a fuel supply system for using it has been developed in various ways.

Recently, DME has attracted attention as a fuel to replace diesel. DME fuel is attracting attention as a clean fuel that replaces diesel because it can reduce fine dust, which is a particulate matter such as black carbon, to a considerable level.

The DME fuel supply system for supplying such DME fuel to a diesel engine is mainly composed of a DME storage tank, a DME injection device, a feed pump, etc. Looking at the operation of the conventionally developed DME fuel supply system, the DME fuel supply system The DME fuel supplied from the DME storage tank is pressurized by the feed pump and then delivered to the DME injection device. Further, in order to increase the use rate of DME fuel in the DME fuel supply system, a fuel recovery pipe for recovering the remaining DME from the DME injection device to the DME storage tank is disposed between the DME injection device and the DME storage tank.

On the other hand, in the DME fuel supply system, it is important to keep the DME fuel in a liquid state by keeping the temperature of the DME fuel low, and for this, it is necessary to properly maintain the temperature of each component constituting the DME fuel supply system. In the conventional DME fuel supply system, a number of cooling fans are used to properly maintain the internal temperature. In particular, since there was a lot of heat generation in the drive motor of the feed pump, the cooling fan for cooling the feed pump was excessively operated, and thus, a noise appeared high and a problem of excessively consuming the power of the battery occurred.

Against this background, the purpose of this embodiment is to provide, in one aspect, a technique for controlling the temperature of the DME fuel supply system. In another aspect, the purpose of this embodiment is to provide a technique for improving the fuel efficiency of a DME fuel supply system. In another aspect, the object of this embodiment is to provide a technique for reducing the manufacturing cost of a DME fuel supply system.

In order to achieve the above object, one embodiment receives DME fuel from a DME (dimethyl ether) storage tank through a fuel supply pipe, supplies the DME fuel to the DME injection device, and drives the driving motor according to the output of the engine. Feed pump with a single stage control; A first temperature sensor for measuring the temperature of the feed pump; As a fan for cooling the feed pump, a first cooling fan for controlling the output according to the measured value of the first temperature sensor; And a second cooling fan mounted on the fuel recovery pipe for recovering the remaining DME and cooling the fuel recovery pipe.

The fuel supply device may further include a DME accumulator that is disposed between the feed pump and the DME injection device and temporarily stores the DME fuel discharged from the feed pump. Here, the DME accumulator can prevent the supply of DME fuel from being smoothly prevented due to the pulsating wave that may occur in the process of injecting fuel from the DME injection device to the engine while temporarily storing the DME fuel. have.

In the fuel supply device, the feed pump may be controlled such that the pressure of the DME accumulator is maintained within a certain range.

Another embodiment, a DME storage tank for storing DME fuel; A feed pump connected to the DME storage tank through a fuel supply pipe, delivering the DME fuel to a DME injection device, and controlling the number of stages of the driving motor according to the output of the engine; A first temperature sensor for measuring the temperature of the feed pump; As a fan for cooling the feed pump, a first cooling fan for controlling the output according to the measured value of the first temperature sensor; A DME injection device that injects the DME fuel into the engine through a DME injector; And a second cooling fan mounted on a fuel recovery pipe for recovering the remaining amount of DME from the DME injection device and cooling the fuel recovery pipe.

The fuel supply system may further include a purge valve purging the overpressure of the DME injection device.

In the fuel supply system, the DME fuel purged from the purge valve may be supplied to the intake system of the engine.

In the fuel supply system, the feed pump can control the number of stages of the drive motor according to the speed of the vehicle.

In the fuel supply system, the feed pump may drive the driving motor to the lowest stage when the speed of the vehicle becomes equal to or less than a predetermined value.

The fuel supply system may further include a DME accumulator disposed between the feed pump and the DME injection device and temporarily storing the DME fuel discharged from the feed pump.

In the fuel supply system, the DME accumulator may incorporate a backflow prevention unit.

As described above, according to the present embodiment, by properly controlling the temperature of the DME fuel supply system, it is possible to prevent excessive cooling fan operation, reduce noise, reduce battery power consumption, and improve DME fuel efficiency. This will improve and reduce the manufacturing cost of the entire DME fuel supply system.

1 is a block diagram of a DME fuel supply system according to an embodiment.
2 is a diagram illustrating a controller and input / output of the controller according to an embodiment.
3 is a view showing a control flow of a controller according to an embodiment.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. It should be noted that in adding reference numerals to the components of each drawing, the same components have the same reference numerals as possible even though they are displayed on different drawings. In addition, in describing the present invention, when it is determined that detailed descriptions of related well-known structures or functions may obscure the subject matter of the present invention, detailed descriptions thereof will be omitted.

In addition, in describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only for distinguishing the component from other components, and the nature, order, or order of the component is not limited by the term. When a component is described as being "connected", "coupled" or "connected" to another component, the component may be directly connected to or connected to the other component, but another component between each component It will be understood that elements may be "connected", "coupled" or "connected".

1 is a block diagram of a DME fuel supply system according to an embodiment.

Referring to FIG. 1, the DME fuel supply system 100 may include a DME fuel supply device 10, a DME storage tank 21, a DME injection device 31, and a DME injector 32.

The DME fuel supplied from the DME storage tank 21 may be delivered to the DME injection device 31 via the DME fuel supply device 21 through the fuel supply pipe 2. In addition, the DME injection device 31 may inject DME fuel through the DME injector 32 to the engine, and deliver the remaining DME amount after injection to the DME storage tank 21 through the fuel recovery pipe 4.

The remaining amount of DME recovered to the DME storage tank 21 is high-temperature and high-pressure fuel, and when it flows into the DME storage tank 21, the temperature of the DME storage tank 21 can be increased while being liquefied. The DME fuel supply system according to an embodiment may keep the average temperature of the DME storage tank 21 low by minimizing the remaining amount of DME recovered.

The DME fuel supply system 100 may further include a fuel filter 12. The fuel filter 12 may purge DME fuel supplied from the DME storage tank 21 to remove impurities of DME fuel.

The fuel filter 12 may be disposed in front of the fuel supply pipe 2, and manual valves V4 and V5 may be disposed before and after it. In addition, different manual valves V7 and V6 may also be connected to the portion where the DME storage tank 21 and the fuel supply pipe 2 are connected and the portion where the fuel recovery pipe 4 is connected. These manual valves (V4, V5, V6 and V7) allow the user to control the flow of DME fuel, as well as to easily replace parts. For example, by closing the manual valves V4 and V5 arranged before and after the fuel filter 12, the user can easily replace the fuel filter 12. The fuel filter 12 may be usefully used in these manual valves V4 and V5 in that the replacement cycle is shorter than other parts.

The pressure of the DME fuel output from the DME storage tank 21 may be measured by the supply pipe pressure sensor P1. In addition, the temperature of the DME fuel output from the DME storage tank 21 may be measured by the supply pipe temperature sensor T4. The values measured by the supply pipe pressure sensor (P1) and the supply pipe temperature sensor (T4) can be transmitted to the controller 40, and the controller 40 is the values measured by the supply pipe pressure sensor (P1) and the supply pipe temperature sensor (T4) It is possible to provide an alarm to the user by using or stop the operation of the DME fuel supply system 100 or adjust the supply speed of the DME fuel.

The DME fuel that has passed through the fuel filter 12 may be discharged to the DME injection device 31 by the feed pump 13.

The feed pump 13 may include a drive motor and a drive driver, where the drive motor may be configured to enable single-stage control. The drive motor includes a gear mechanically, and the number of stages may be controlled by these gears, or the number of stages may be controlled by electrical control. The following describes an example in which the driving motor is singularly controlled by electrical control for convenience of explanation.

The driving driver can control the driving motor in a single stage by controlling the output-for example, the current-to a discontinuous value. The driving driver may include a power conversion circuit. By controlling the output setting value of the power conversion circuit-for example, a feedback reference value-to a discontinuous value, the driving motor may be single-controlled.

In the feed pump 13, the number of stages of the driving motor may be controlled according to the output of the engine. For example, when the output of the engine is high, the number of stages of the driving motor may be controlled to a high level, and when the output of the engine is low, the number of stages of the driving motor may be controlled to a low level. The controller 40 may control the driving driver to control the number of stages of the driving motor. In addition, the controller 40 may check the output of the engine by measuring or estimating the condition of other parts of the vehicle. The controller 40 can check the output of the engine through the vehicle speed. For example, when the vehicle speed is high, the controller 40 may control the number of stages of the driving motor to be high, and when the vehicle speed is low, the controller 40 may control the number of stages of the drive motor to be low. The controller 40 may check the output of the engine through the engine speed (rpm). For example, when the rpm is high, the controller 40 may control the drive motor to a high stage, and when the rpm is low, the controller 40 may control the drive motor to a low stage.

A cooling device may be attached to the feed pump 13 alone. For example, the first cooling fan F1 may be attached to the feed pump 13 alone. In the prior art, the cooling device attached to the feed pump 13 is also involved in cooling of other parts, but in the DME fuel supply system 100 according to an embodiment, the cooling device may be attached to the feed pump 13 alone. .

The operation of the first cooling fan F1 may be controlled according to the state of the feed pump 13. For example, the first cooling fan F1 may increase the output for cooling when the feed pump 13 is high temperature, and reduce the output for cooling when the feed pump 13 is low temperature. When the temperature of the feed pump 13 is within a predetermined range set in advance, the first cooling fan F1 may not operate. For example, when the feed pump 13 falls within a preset low temperature range, the first cooling fan F1 may not operate. The drive motor of the feed pump 13 controls the number of stages according to the output of the engine. For example, when the vehicle is in an idle state, the drive motor of the feed pump 130 is driven or not driven at a low stage. It may not. In this state, the feed pump 13 may maintain a low temperature state. At this time, the first cooling fan F1 may confirm that the feed pump 13 is in a low temperature state, and may reduce output or not operate. As a result, when the engine output is low, for example, when the vehicle is in an idle state, the output of the first cooling fan F1 is lowered, or the first cooling fan F1 is not operated. By this, it is possible to minimize the effect of noise caused by the first cooling fan (F1). In general, the user becomes more sensitive to noise when the engine output is low, and the DME fuel supply system 100 according to an embodiment reduces the output of the first cooling fan F1 when the engine output is low, thereby reducing noise. Can be minimized.

The DME fuel supply device 10 may further include a feed pump temperature sensor T1 that measures the temperature of the pipe pump 13. And, the first cooling fan F1 for cooling the feed pump 13 may control the output according to the measured value of the feed pump temperature sensor T1. For example, when the measured value of the feed pump temperature sensor T1 is low, the first cooling fan F1 reduces the output, and when the measured value of the feed pump temperature sensor T1 is high, the first cooling fan F1 ) Can increase the output.

Unlike the other components in the DME fuel supply system 100, a drive system device-a driving motor-is used for the feed pump 13, and due to such a drive system device, the feed pump 13 generates heat itself. The heat generated from the feed pump 13 exerts a high influence on the overall temperature management of the DME fuel supply system 100. For example, when the calorific value of the feed pump 13 is high, the temperature of the DME fuel supply system 100 is high, and when the calorific value of the feed pump 13 is low, the temperature of the DME fuel supply system 100 may be low. have.

DME fuel supply system 100 according to an embodiment can minimize the heat generation of the feed pump 13 by driving the feed pump 13 variably according to the output of the engine. On the other hand, the first cooling fan (F1) serves to lower the temperature of the feed pump 13, but also acts as a heat source and a noise source itself, so if the heat of the feed pump 13 is high, the second cooling The temperature of the DME fuel supply system 100 may be additionally increased due to an increase in the amount of heat generated by the fan F1, and the DME fuel supply system 100 according to an exemplary embodiment is secondary by lowering the temperature of the feed pump 13. The heat generation amount of the first cooling fan F1 can also be reduced, and accordingly, the temperature of the DME fuel supply system 100 as a whole can be reduced.

When the temperature of the feed pump 13 is high, the temperature of the DME fuel rises, and accordingly, the amount of DME fuel consumed by the DME injection device 31 decreases, and conversely, the amount of DME recovered by the fuel recovery pipe increases. . The DME remaining amount is condensed while being recovered to the DME storage tank 21. At this time, there is a problem that the temperature of the DME storage tank 21 increases due to heat due to condensation. The DME fuel supply system 100 according to an embodiment may lower the temperature of the feed pump 13, and accordingly, maintain the temperature of the DME fuel low. And, as a result, it is possible to increase the efficiency of DME fuel consumption in the DME injection device 31, and it is possible to minimize the remaining amount of DME recovered by the fuel recovery pipe. And, by reducing the remaining DME, it is possible to keep the temperature of the DME storage tank 21 low.

In addition, a second cooling fan (F2) may be attached to the fuel recovery pipe (4) for recovering the remaining amount of DME. In one embodiment, the temperature of the fuel recovery pipe (4) is also relatively lowered, so that the second cooling fan (F2) ) Can be minimized, and noise caused by the second cooling fan (F2) can also be minimized.

Before and after the second cooling fan F2, a fuel purge temperature sensor T2 for measuring the temperature of the fuel purged and a fuel recovery temperature sensor T3 for measuring the temperature of the fuel recovered by the DME storage tank 21 ) May be arranged, the second cooling fan F2 may control the output according to the measured value of the fuel purge temperature sensor T2 and / or the fuel recovery temperature sensor T3.

Meanwhile, a DME accumulator 11 for temporarily storing DME fuel discharged from the feed pump 13 may be further disposed between the feed pump 13 and the DME injection device 31.

The DME accumulator 11 has a built-in backflow prevention unit, and can prevent DME fuel from flowing back.

The accumulator pressure sensor P2 may be attached to the DME accumulator 11. Then, the feed pump 13 may be controlled so that the pressure of the DME accumulator 11 is maintained within a predetermined range according to the measured value of the accumulator pressure sensor P2. When there is no DME accumulator 11, when the output of the engine suddenly changes, DME fuel may not be supplied to the DME injection device 31. As it is buffered, it can flexibly respond to sudden fluctuations in engine output.

Between the DME fuel supply device 10 and the DME injection device 31, solenoid valves V1 and V2 for controlling the flow of DME fuel may be arranged. The first solenoid valve V1 may be disposed in the fuel supply pipe 2 to control the flow of DME fuel supplied from the DME fuel supply device 10 to the DME injection device 31. In addition, the second solenoid valve V2 may be disposed in the fuel recovery pipe 4 to control the flow of DME fuel recovered from the DME injection device 31 to the DME fuel supply device 10.

The DME injection device 31 may inject DME fuel supplied through the fuel supply pipe 2 into the engine using the DME injector 32.

The DME injection device 31 may inject DME fuel supplied through the fuel supply pipe 2 into the engine according to the output of the engine. At this time, the DME fuel may be temporarily placed in an overpressure state. The DME injection device 31 may further include a purge valve 35 for purging the overpressure of DME fuel.

On the other hand, DME fuel purged from the purge valve 35 may not be discharged into the air and may be supplied to the intake system of the engine. Through this discharge path, the reuse rate of DME fuel can be increased. In addition, it is possible to reduce the DME fuel (remaining DME) recovered by the fuel recovery pipe 4.

Two paths may be connected to the purge valve 35, the first path may be connected to the intake duct of the engine, and the second path may be directly connected to the engine. In addition, a third solenoid valve V3 may be disposed in one of the two paths, and both paths may be used or only one of them may be used according to the control of the controller 40.

The purge valve 35 may be configured in the form of a relief valve. The relief valve may purge using energy generated by the overpressure of the DME injection device 31.

In the DME injection device 31, the engine oil may leak in the DME injection device 31 according to the overpressure of DME fuel. In this case, the DME injection device 31 may be damaged due to lubrication problems. have. In order to prevent this, the regulator 33 may be further disposed. The regulator 33 detects the overpressure of the DME injection device 31, and when the DME injection device 31 is in an overpressure state, may transfer some of the DME fuel to the fuel recovery pipe 4.

A check valve 34 is further included between the fuel recovery pipe 4 and the regulator 33, and the DME fuel is refluxed from the fuel recovery pipe 4 to the regulator 33 by the check valve 34. Can be prevented.

The DME injector 32 may inject the DME fuel of the DME injection device 31 into the engine, and the remaining DME remaining after injection may be delivered to the fuel recovery pipe 4.

The remaining amount of DME delivered to the fuel recovery pipe 4 is recovered to the DME storage tank 21, and the DME fuel of the DME storage tank 21 can be efficiently managed according to the remaining DME amount. A fuel gauge G1 may be attached to the DME storage tank 21, and the controller 40 may manage the DME fuel of the DME storage tank 21 using the measured value of the fuel gauge G1.

The DME fuel supply device 10 may include a DME leak detector 14. The controller 40 can safely manage the DME fuel in the vehicle using the measured values of the DME leak detector 14.

Each of the components of the above-described DME fuel supply system 100 may be controlled by the controller 40. The connection relationship between various measured values and / or information provided to the controller 40 and components controlled by the controller 40 will be described with reference to FIG. 2.

2 is a diagram illustrating a controller and input / output of the controller according to an embodiment.

Referring to FIG. 2, the controller 40 includes an ignition key, a vehicle speed sensor, a fuel gauge G1, a DME leak detector 14, a plurality of pressure sensors P1 and P2, and a plurality of temperature sensors T1 to T4. Measurements and / or information may be collected from the back.

The controller 40 can monitor the KEYON signal from the ignition key. Then, the controller 40 can inject DME fuel into the engine after confirming the KEYON signal.

The controller 40 may receive a vehicle speed measurement value from the vehicle speed sensor. In addition, the controller 40 may control the number of feed pumps according to the vehicle speed measurement value.

The controller 40 may receive a measurement value for the amount of DME fuel in the DME storage tank from the fuel gauge G1, and display an alarm to the user according to the measurement value.

The controller 40 may receive DME leak information from the DME leak detector 14 and alarm the DME leak information to the user.

The controller 40 may check the pressure of the DME fuel output from the DME storage tank from the first pressure sensor P1, and when the pressure is low, an alarm may be provided to the user.

The controller 40 may check the discharge pressure of the feed pump from the second pressure sensor P2, and if this pressure is low, provide an alarm to the user or increase the number of stages of the drive driver to control the discharge pressure of the feed pump. .

The controller 40 may receive a measurement value for the surface temperature of the feed pump from the first temperature sensor T1. Then, the controller 40 may control the output of the first cooling fan by using these measured values.

The controller 40 may receive a measurement value for the temperature of DME fuel that is purged from the second temperature sensor T2 and flows into the fuel recovery pipe. In addition, the controller 40 may provide an alarm to the user or control the output of the second cooling fan using these measured values.

The controller 40 may receive a measurement value for the temperature of the DME fuel recovered from the third temperature sensor T3 to the DME storage tank. In addition, the controller 40 may provide an alarm to the user or control the output of the second cooling fan using these measured values.

The controller 40 may receive a measurement value for the temperature of DME fuel supplied to the fuel supply pipe from the fourth temperature sensor T4. In addition, the controller 40 may provide an alarm to the user or control the output of the first cooling fan using these measured values.

The controller 40 may perform a control algorithm using the above-described measured values and / or information and, as a result, generate control values for various devices.

The controller 40 may control the flow of DME fuel in the fuel supply pipe by controlling the first solenoid valve V1. For example, when the above-described measurement values are not included in the normal range, the supply of DME fuel may be blocked using the first solenoid valve V1.

The controller 40 may control the flow of DME fuel in the fuel recovery pipe by controlling the second solenoid valve V2. For example, when the first solenoid valve V1 is blocked according to various controls, the controller 40 may also block the second solenoid valve V2.

The controller 40 may control the third solenoid valve V3 to diversify the output path from the purge valve.

The controller 40 may check the output of the engine and control the speed of the feed pump by controlling the number of driving drivers in accordance with the output of the engine.

The controller 40 may control cooling of the feed pump by controlling the first cooling fan F1 according to the measured value of the first temperature sensor T1.

The controller 40 may control the temperature of the recovered DME fuel by controlling the second cooling fan F2 according to the measured values of the second temperature sensor T2 and / or the third temperature sensor T3.

The controller 40 may calculate or measure the NOx, carbon monoxide (CO), and particulate matter (PM) using its own analysis or a separate sensor, and transmit the result to the exhaust gas detection device.

Then, the controller 40 may transmit measurement values, control values, and alarm values to the display device in order to provide various information to the user.

3 is a view showing a control flow of a controller according to an embodiment.

Referring to FIG. 3, the controller can confirm KEYON (S300).

Then, when KEYON is confirmed, the controller may receive a measurement value for the vehicle speed (S302).

Then, the controller may control the number of feed pumps according to the vehicle speed (S304).

Then, the controller may receive a measurement value for the surface temperature of the feed pump (S306).

Then, the controller may control the output of the cooling fan attached to the feed pump according to the surface temperature of the feed pump (S308).

Then, the controller may receive a measurement value for the temperature of the fuel recovery pipe (S310).

Then, the controller may control the output of the cooling fan attached to the fuel recovery pipe according to the temperature of the fuel recovery pipe (S312).

As described above, according to the present embodiment, by properly controlling the temperature of the DME fuel supply system, it is possible to prevent excessive cooling fan operation, reduce noise, reduce battery power consumption, and improve DME fuel efficiency. This will improve and reduce the manufacturing cost of the entire DME fuel supply system.

The terms "include", "compose" or "have" as described above mean that the corresponding component can be inherent unless otherwise stated, and do not exclude other components. It should be construed that it may further include other components. All terms, including technical or scientific terms, have the same meaning as generally understood by a person skilled in the art to which the present invention belongs, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted as being consistent with the meaning of the context of the related art, and are not to be interpreted as ideal or excessively formal meanings unless explicitly defined in the present invention.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and variations without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the claims below, and all technical spirits within the equivalent range should be interpreted as being included in the scope of the present invention.

Claims (10)

A feed pump receiving DME fuel from a DME (dimethyl ether) storage tank through a fuel supply pipe, supplying the DME fuel to a DME injection device, and controlling the number of stages of a driving motor according to an engine output;
A first temperature sensor for measuring the temperature of the feed pump which is variable according to the change in the number of stages of the drive motor;
As a fan for cooling the feed pump, a first cooling fan for controlling the output according to the measured value of the first temperature sensor;
A second cooling fan mounted on a fuel recovery pipe for recovering the remaining DME, and cooling the fuel recovery pipe;
A second temperature sensor for measuring the temperature of the DME fuel recovered through the fuel recovery pipe, and measuring at the front end of the second cooling fan; And
A third temperature sensor that measures the temperature of the DME fuel recovered through the fuel recovery pipe, but measures it at the rear end of the second cooling fan.
Including,
The first cooling fan increases the output for cooling the feed pump when the temperature of the feed pump is high, and reduces the output for cooling when the temperature of the feed pump is low, but corresponds to a preset low temperature range. If it stops working,
The second cooling fan controls output according to the measured value of the second temperature sensor and the measured value of the third temperature sensor.
Fuel supply. According to claim 1,
And a DME accumulator disposed between the feed pump and the DME injection device and temporarily storing the DME fuel discharged from the feed pump. According to claim 2,
The feed pump is a fuel supply device that is controlled so that the pressure of the DME accumulator is maintained within a certain range. A DME storage tank for storing DME fuel;
A feed pump connected to the DME storage tank through a fuel supply pipe, delivering the DME fuel to a DME injection device, and controlling the number of stages of a driving motor according to an engine output;
A first temperature sensor for measuring the temperature of the feed pump which is variable according to the change in the number of stages of the drive motor;
As a fan for cooling the feed pump, a first cooling fan for controlling the output according to the measured value of the first temperature sensor;
A DME injection device that injects the DME fuel into the engine through a DME injector;
A second cooling fan mounted on a fuel recovery pipe for recovering the remaining amount of DME from the DME injection apparatus, and cooling the fuel recovery pipe;
A second temperature sensor for measuring the temperature of the DME fuel recovered through the fuel recovery pipe, and measuring at the front end of the second cooling fan;
A third temperature sensor measuring a temperature of the DME fuel recovered through the fuel recovery pipe, and measuring at a rear end of the second cooling fan; And
Purge valve purging the overpressure of the DME injection device
Including,
The DME fuel purged from the purge valve is supplied to the intake system of the engine,
The first cooling fan increases the output for cooling the feed pump when the temperature of the feed pump is high, and reduces the output for cooling when the temperature of the feed pump is low, but corresponds to a preset low temperature range. If it stops working,
The second cooling fan controls output according to the measured value of the second temperature sensor and the measured value of the third temperature sensor.
Fuel supply system. delete delete The method of claim 4,
The feed pump is a fuel supply system that controls the number of stages of the drive motor according to the speed of the vehicle. The method of claim 7,
The feed pump is a fuel supply system that drives the driving motor to the lowest stage when the speed of the vehicle becomes below a certain value. The method of claim 4,
And a DME accumulator disposed between the feed pump and the DME injection device and temporarily storing the DME fuel discharged from the feed pump. The method of claim 9,
The DME accumulator is a fuel supply system with a built-in backflow prevention unit.

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