KR20070073697A - Diesel-lng dual fuel system - Google Patents

Abstract

A diesel-LNG dual fuel system is provided to supply diesel fuel and LNG into a cylinder in a mixed state and readily control the supply amount of the diesel fuel and LNG. A diesel-LNG dual fuel system includes a fuel injection part(200), a fuel injection pump(210), a cylinder(110), an accelerator sensor(230), a noise sensor(240), a suction part(300), a gas supply part(400), and an LNG tank(410). The fuel injection part injects a diesel fuel into the cylinder. The fuel injection pump supplies the diesel fuel into the cylinder. The accelerator sensor transmits data to a controller(500) to control a diesel injection amount. The noise sensor transmits data of an operation state of the fuel injection pump to control supply of the LNG. The suction part sucks the air from the exterior. The gas supply part is connected to the suction port to supply the LNG. The LNG tank stores the LNG.

Description

Diesel L & C System {DIESEL-LNG DUAL FUEL SYSTEM}

1 is a schematic diagram of a diesel LNG mixing system according to the present invention.

2 is a block diagram of a diesel LNG mixing system according to the present invention.

※ Explanation of symbols used in main part of drawing

100: engine 110: cylinder

200: fuel injection unit 210: fuel injection pump

220: diesel injection amount control controller 230: accelerator sensor

240: noise sensor 300: intake portion

310: intake pipe 320: mixer

330: intake manifold 400: gas supply unit

410: LNG tank 420: carburetor

430: cooling water line 440: gas supply shutoff valve

450: pressure reducer 460: professional valve

500 control unit 510 electronic control unit (ECU)

520: selector switch 530: transformer

540: lamp

The present invention relates to a diesel LNG blending system for mixing diesel and LNG into a cylinder of a diesel engine to be combusted together, and more specifically, mixing diesel fuel and LNG into a cylinder of an engine even if a separate nozzle is not additionally installed. The present invention relates to a diesel LNG mixed-use system that can be supplied and can be easily controlled by an additionally installed electronic control unit (ECU).

In general, diesel engines have the advantage of obtaining greater output than gasoline engines or gas engines, but they generate more emissions than gasoline engines or gas engines, as well as the environment caused by NOx or SOx mixed with exhaust gas. There is a problem of pollution, and also has the disadvantage of being more expensive than gas (LPG, LNG) economically. In order to overcome such problems of diesel engines, in particular, environmental problems, research into technologies for converting diesel gas mixing systems has been actively conducted.

As a conventional diesel gas mixing system, Korean Laid-Open Patent Publication No. 2007-0048684 discloses a system of diesel-gas mixing engine and its control method. The "diesel-gas mixed engine system and control method thereof" relates to a system for replacing diesel fuel with gas fuel based on a diesel engine, and supplying gas fuel after ignition with diesel fuel to burn the diesel fuel. The present invention relates to a control system and a control method of a mixed engine. More specifically, the "system of diesel-gas blended engine and its control method" relates to a multi point injection (MPI) supply method, and inputs and outputs sensor signals inputted and output from an electric control unit (ECU) of a diesel engine. It is applied without change, and separate gas ECU is configured to cut off diesel injector driving signal and control diesel injector through gas ECU. Also, it is configured to drive diesel and gas injector at the same time through gas ECU through gas ECU.In addition, the combustion stability and efficiency of the blended engine are improved by adjusting the intake air flow rate separately from the combustion stability through the control of fuel injection in the mixed engine. Intake air flow rate control device is configured in the intake air flow path.

However, the "Diesel-Gas Mixture Engine System and its Control Method" requires a problem of having a separate nozzle at the top of each cylinder header and high precision control of the injection point of diesel fuel and the injection point of gas. The disadvantage is that. Furthermore, in order to be applied to a conventional vehicle, a separate nozzle must be installed on the upper part of the cylinder header, and a high precision ECU must be installed to control precisely the injection timing. The disadvantage is that it is expensive.

Accordingly, an object of the present invention is to provide a mixture of diesel fuel and LNG to the cylinder of the engine even if a separate nozzle is not installed, and to provide a separate electronic control unit (ECU) so that the supply amount of diesel fuel and LNG can be easily controlled. It is to provide a diesel LNG mixed-use system that is additionally installed.

The above object of the present invention,

A fuel injection unit for injecting and supplying diesel fuel to a cylinder of an engine, an intake unit for supplying air to the cylinder, a gas supply unit connected to supply LNG to the intake unit, and connected to the fuel injection unit and a gas supply unit And a control unit for controlling each, and is achieved by providing a diesel LNG mixing system, characterized in that the diesel fuel and LNG are mixed and burned together in the cylinder.

According to a preferred feature of the invention, the fuel injection unit and the fuel injection pump for injecting diesel fuel to the cylinder, the fuel injection pump is attached to the fuel injection pump and electrically controlled with the controller so that the injection amount of the diesel fuel injected into the cylinder can be adjusted And an accelerator sensor connected to the fuel injection pump and electrically connected to the fuel injection pump so as to transmit data about the state of the accelerator to the controller.

According to a further preferred feature of the invention, the fuel injection unit further includes a noise sensor attached to the fuel injection pump and electrically connected to the control unit, the noise sensor is configured to receive data regarding the operating state of the fuel injection pump The control unit transmits the data to the gas supply unit after analyzing the received data and controls the supply of LNG.

According to a further preferred feature of the present invention, the intake unit is combined with the intake pipe and the gas supply unit and the pipe is connected to the intake pipe through which air is introduced from the outside, and air and LNG, and the mixer And an intake manifold connected with the air guide to guide the air and LNG to the cylinder.

According to a further preferred feature of the present invention, the gas supply unit is connected to the LNG tank, the vaporizer and the vaporizer supplied to the gas supplied in a liquid state, and the cooling is provided to provide heat to the vaporizer A gas supply shutoff valve installed between the waterline and the vaporizer and the intake unit, the gas supply shutoff valve electrically connected to the control unit so that supply of gasified LNG passing through the vaporizer to the intake unit can be controlled; And a pressure reducer installed between the gas supply shutoff valve and the intake part so that the pressure of the LNG can be adjusted.

According to a further preferred feature of the present invention, the gas supply unit is provided between the pressure reducer and the intake unit, and a professional valve electrically connected to the control unit so that the proportional supply of LNG to the intake unit can be controlled It further includes.

According to a further preferred feature of the invention, the control unit is provided with an electronic control unit connected to the fuel injection unit and the gas supply unit, and is connected to the electronic control unit to convert the diesel combustion mode to the diesel LNG mixed mode And a selection switch and a transformer connected to the electronic control unit and supplying a proper voltage.

According to a further preferred feature of the invention, the control unit further comprises a lamp connected to the electronic control unit and provided to display the mixed combustion state of the engine.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, this is only to describe in detail enough to be able to easily carry out the invention by those skilled in the art, which does not mean that the technical spirit and scope of the present invention is limited.

1 is a schematic diagram of a diesel LNG mixing system according to the present invention, Figure 2 is a block diagram of a diesel LNG mixing system according to the present invention.

As shown in FIG. 1, the diesel LNG mixing system according to the present invention includes a fuel injection unit, an intake unit, a gas supply unit, and a control unit. The cylinder of the engine is supplied with diesel fuel from a fuel injection unit and supplied with a mixture of LNG and air from a gas supply unit and an intake unit, and the supply amount of diesel fuel and LNG is controlled by a controller. The fuel injection unit, the intake unit, the gas supply unit, and a detailed description of the control unit will be described with reference to FIG. 2.

The fuel injection unit 200 serves to inject and supply diesel fuel to the cylinder 110 of the engine 100, as shown in FIG. 2, a fuel injection pump 210 and a diesel injection control controller 220. , Including the accelerator sensor 230, preferably further includes a noise sensor 240.

The fuel injection pump 210 is a pump for injecting diesel fuel into the cylinder 110, and the diesel fuel may be supplied to the combustion chamber of the cylinder 110 by the fuel injection pump 210, as described below. The injection amount of diesel is controlled by the diesel injection amount control controller 220 attached to the 210 may be supplied to the combustion chamber of the cylinder (110).

That is, the amount of diesel fuel supplied to the combustion chamber of the cylinder 110 needs to be adjusted, and the diesel injection amount control controller 220 implements this. The diesel injection control controller 220 is attached to the fuel injection pump 210 and electrically connected to the control unit 500 serves to adjust the injection amount of the diesel fuel injected from the fuel injection pump 210 to the cylinder 110. Specifically, the diesel injection amount control controller 220 is controlled by the electronic control unit (ECU) 510 of the control unit 500.

Here, the accelerator sensor 230 transmits data to the control unit 500 so that the control unit 500 controls the diesel injection control controller 220, and the electronic control unit of the control unit 500. (ECU) 510 is electrically connected. The accelerator sensor 230 transmits data on the state of the accelerator to the electronic control unit (ECU) 510 of the control unit 500. The control unit 500 receives data on the state of the accelerator from the accelerator sensor 230. The electronic control unit (ECU) 510 of the control unit transmits the data so that the diesel injection control controller 220 adjusts the diesel fuel injection amount of the fuel injection pump 210 according to the analyzed information. The accelerator sensor 230 is attached to the fuel injection pump 210, preferably attached to the acceleration lever of the fuel injection pump 210 connected to the accelerator pedal.

In addition, the noise sensor 240 transmits data on the operating state of the fuel injection pump 210 to the control unit 500 and serves to enable the control unit 500 to control the supply of LNG. That is, the noise sensor 240 is attached to the fuel injection pump 210 and is electrically connected to the electronic control unit (ECU) 510 of the controller 500. The data on the operation state of the fuel injection pump 210 is provided. Is transmitted to the electronic control unit (ECU) 510 of the control unit 500, the electronic control unit (ECU) 510 analyzes the received data and then transmits the data to the gas supply unit 400 to supply the LNG. To be controlled. At this time, when the fuel injection pump 210 operates, that is, when there is noise, the diesel fuel is supplied to the cylinder 110, so that the electronic control unit (ECU) 510 of the control unit 500 is a gas supply unit. The data is transmitted to supply LNG at 400. On the other hand, when the fuel injection pump 210 does not operate, that is, there is no noise, the starting state is turned off, so that the electronic control unit (ECU) 510 of the control unit 500 transmits data to the gas supply unit 400. The LNG supply is to be cut off, a more detailed description thereof will be described later.

The intake unit 300 serves to supply air to the cylinder 110 by sucking air from the outside, and as shown in FIG. 2, the intake unit 300 includes an intake pipe 310, a mixer 320, Intake manifold 330 is included, and air introduced from the outside through the intake pipe 310 is mixed with LNG in the mixer 320 and guided to the cylinder 110 through the intake manifold 330. That is, the air flowing through the intake pipe 310 is supplied to the cylinder 110 through the intake manifold 330 via the mixer 320, at this time, the gas supply unit 400 connected to the mixer 320 and the pipes. LNG is supplied to the mixer 320 and supplied to the cylinder 110 through the intake manifold 330 in a state in which LNG and air are mixed in the mixer 320. Here, the intake manifold 330 serves to uniformly distribute the air and LNG mixed in the mixer 320 to be supplied to the cylinder (110).

The gas supply unit 400 is connected to the intake unit 300 and serves to supply LNG. Specifically, the gas supply unit 400 supplies LNG to the mixer 320 of the intake unit 300. As shown in FIG. 2, the gas supply unit 400 includes an LNG tank 410, a vaporizer 420, a cooling water line 430, a gas supply shutoff valve 440, and a pressure reducer 450. And, preferably further comprises a professional valve 460.

LNG tank 410 is a low temperature tank to store the gas at a temperature condition of approximately -163 ℃, therefore LNG is stored in a liquid state in the LNG tank 410, supplying the liquid fuel to the vaporizer 420 Done.

Vaporizer 420 serves to change the LNG fuel supplied in the liquid state from the LNG tank 410 into the gas state to be easily mixed with air. In order to gasify the liquid LNG fuel in the vaporizer 420, heat must be provided, for which a cooling water line 430 is provided. That is, the cooling water line 430 serves to provide heat to the vaporizer 420, and the cooling water line 430 is installed to circulate the engine 100 and the vaporizer 420. Therefore, the liquid LNG fuel in the vaporizer 420 may be vaporized into gas by the hot water discharged from the engine 100, and the cold water, which is deprived of heat from the vaporizer 420, is returned to the engine 100. The cooling water will circulate.

The gas supply shutoff valve 440 is installed between the vaporizer 420 and the intake unit 300 to control the supply and shutoff of the LNG as the gas to the intake unit 300 via the vaporizer 420. The gas supply shutoff valve 440 is controlled by the control unit 500 that is electrically connected, specifically, is connected to and controlled by the electronic control unit (ECU) 510 of the control unit 500. As described above, the electronic control unit (ECU) 510 of the controller 500 is connected to the noise sensor 240 attached to the fuel injection pump 210 of the fuel injection unit 200, and the noise sensor 240 is When data on the operating state of the fuel injection pump 210 is transmitted to the ECU 510, the ECU 510 analyzes the received data and, when there is no noise, the gas supply shutoff valve. 440 is operated to stop the supply of LNG. Meanwhile, the gas supply shutoff valve 440 is controlled by the electronic control unit (ECU) 510 only when the selection switch 520 of the controller 500 to be described later is in the mixed mode, and the selection switch 520. ) Is always in the closed state in the diesel combustion mode.

The gas regulator 450 serves to regulate the pressure of the LNG supplied to the intake unit 300, and is installed between the gas supply shutoff valve 440 and the intake unit 300. More specifically, the pressure reducer 450 serves to lower the pressure of LNG supplied through the vaporizer 420 to an appropriate pressure.

A proportional gas control valve 460 is installed between the pressure reducer 450 and the intake part 300 to proportionally intake LNG lowered to an appropriate pressure by the pressure reducer 450. It serves to be supplied to the mixer 320 of 300. The professional valve 460 is controlled by a control unit 500 that is electrically connected, specifically, an electronic control unit (ECU) 510 of the control unit 500, and the accelerator sensor 230 is an electronic control unit (ECU). When the data on the state of the accelerator is transmitted to the 510, the electronic control unit (ECU) 510 controls the professional valve 460 according to the data.

The control unit 500 is electrically connected to the fuel injection unit 200 and the gas supply unit 400 and controls each of the control unit 500, an electric control unit (ECU) 510, and a selection switch 520. It is made, including a transformer (Transformer) 530, preferably comprises a lamp 540 further.

The electronic control unit (ECU) 510 is directly connected to the fuel injection unit 200 and the gas supply unit 400 to control each of them. More specifically, the accelerator sensor of the fuel injection unit 200 ( 230 and the diesel injection control controller 220 and the noise sensor 240, and the gas supply blocking valve 440 and the professional valve 460 of the gas supply unit 400 is electrically connected to transmit and receive data to control Play a role. That is, the electronic control unit 510 receives data on the state of the accelerator from the accelerator sensor 230, so that the injection amount of the diesel fuel injected from the fuel injection pump 210 to the cylinder 110 can be adjusted. Control the controller 220, analyzes the data on the operating state of the fuel injection pump 210 received from the noise sensor 240 to control the operation of the gas supply shutoff valve 440, and also the accelerator sensor 230 The professional valve 460 is controlled so that the LNG supplied from the gas supply unit 400 to the mixer 320 of the intake unit 300 is proportionally supplied according to the data on the accelerator state received from the controller.

The selection switch 520 is connected to the electronic control unit 510 to convert the diesel combustion mode into the diesel LNG mixed mode, and the transformer 530 is connected to the electronic control unit 510 to supply an appropriate voltage. Do it. In addition, the lamp 540 is connected to the electronic control unit 510 is provided to display whether the diesel LNG mixed combustion state of the engine 100.

Hereinafter will be described the operation of the diesel LNG mixing system according to the present invention with reference to FIG. First, when the engine 100 is turned on, diesel fuel is injected and supplied from the fuel injection pump 210 to the cylinder 110 to drive the vehicle. When the selection switch 520 is selected as the diesel LNG mixed mode, The accelerator sensor 230 transmits data on the state of the accelerator to the electronic control unit (ECU) 510, and the electronic control unit (ECU) 510 is connected to the state of the accelerator received from the accelerator sensor 230. By analyzing the data for controlling the diesel injection amount control controller 220 according to the analyzed information to adjust the injection amount of the diesel fuel injected from the fuel injection pump 210 to the cylinder (110).

In addition, the electronic control unit (ECU) 510 opens the gas supply shutoff valve 440 so that the LNG is supplied while controlling the injection amount of the diesel fuel so that the LNG is supplied to the mixer 320. Here, the LNG is present in the liquid state in the LNG tank 410 to maintain approximately -163 ℃ as described above, but gasified by the water circulated through the cooling water line 430 in the vaporizer 420 and the pressure reducer ( After adjustment to the appropriate pressure at 450 may be supplied to the mixer 320 in proportion by the professional valve 460.

When the gas supply shutoff valve 440 is opened, LNG is supplied through a supply line connected to the mixer 320. At this time, since the LNG supply line is higher than the pressure of the intake part 300, the intake part 300 is supplied to the intake part 300. After being sucked in and mixed with air in the mixer 320, it is uniformly distributed through the intake manifold 330 and supplied to the cylinder 110.

In this case, when the speed becomes high, that is, when the accelerator pedal is pressed, the electronic control unit (ECU) 510 receives the data on the state of the accelerator pedal from the accelerator sensor 230 and analyzes the diesel injection amount control controller 220. To control the injection amount of the diesel fuel injected into the cylinder 110 from the fuel injection pump 210 to reduce, the amount of LNG mixed with the air is relatively increased. Accordingly, the amount of diesel fuel supplied to the cylinder 110 is reduced and the amount of LNG is increased. Accordingly, the generation of NOx or SOx soot generated during combustion of the diesel fuel is reduced, so that the effect of soot reduction can be obtained. In addition, the burning of high-calorie LNG allows for greater output.

As described above, according to the diesel LNG mixing system according to the present invention, the smoke formed by mixing the diesel and the LNG is combusted, so that the smoke can be drastically reduced as compared with the conventional diesel engine.

In addition, by reducing the amount of diesel fuel and increasing the amount of LNG fuel during high-speed driving of the vehicle, the effect of the smoke reduction can be maximized, it is possible to obtain a larger output due to the combustion of high calorie LNG.

In addition, since a gas supply unit and an electronic control unit (ECU) can be additionally installed and used in a conventionally used diesel engine, it can be installed relatively easily in a conventional vehicle model, and a separate nozzle or the like is not required, so that it can be installed at low cost. Also, a system in which diesel and LNG are mixed and burned can be used.

Claims (8)

A fuel injection unit for supplying diesel fuel to a cylinder of an engine; An air intake unit for supplying air to the cylinder; A gas supply unit connected to supply LNG to the intake unit; And a control unit connected to the fuel injection unit and the gas supply unit to control each of the fuel injection unit and the gas supply unit, wherein the diesel fuel and LNG mixture is combusted by mixing the diesel fuel and the LNG. The method of claim 1, The fuel injection unit is a fuel injection pump for injecting diesel fuel to the cylinder, a diesel injection amount control controller attached to the fuel injection pump and electrically connected to the control unit to control the injection amount of the diesel fuel injected into the cylinder and And an accelerator sensor attached to the fuel injection pump and electrically connected to transmit data on the state of the accelerator to the controller. The method of claim 2, The fuel injection unit further includes a noise sensor attached to the fuel injection pump and electrically connected to the control unit, wherein the noise sensor transmits data regarding an operating state of the fuel injection pump to the control unit, and the control unit receives the control unit. And analyzing the data and transmitting the data to the gas supply unit to control the supply of LNG. The method of claim 1, The intake unit is coupled to the intake pipe and connected to the gas supply unit and the pipe so as to mix air and LNG, the air inlet pipe from the outside, and connected to the mixer, the air and LNG is the cylinder Diesel LNG mixing system comprising an intake manifold for guiding to be uniformly distributed. The method of claim 1, The gas supply unit is connected between the LNG tank, a vaporizer connected to the LNG tank and gasified LNG supplied in a liquid state, a cooling water line provided to provide heat to the vaporizer, and the vaporizer and the intake unit. And a gas supply shutoff valve electrically connected to the control unit so that the supply block of gasified LNG passing through the vaporizer to the intake unit can be controlled, and the pressure of the LNG supplied to the intake unit can be adjusted. Diesel LNG mixing system comprising a pressure reducer provided between the gas supply shutoff valve and the intake portion. The method of claim 5, The gas supply unit further includes a professional valve installed between the pressure reducer and the intake unit and electrically connected to the control unit to control the proportional supply of LNG to the intake unit. Intercourse system. The method according to any one of claims 1 to 6, The control unit includes an electronic control unit connected to the fuel injection unit and the gas supply unit, a selection switch connected to the electronic control unit and provided to convert a diesel combustion mode into a diesel LNG mixed mode, and connected to the electronic control unit. And a transformer for supplying an appropriate voltage. The method of claim 7, wherein The control unit further comprises a lamp connected to the electronic control unit and provided to display a mixed combustion state of the engine.

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