KR20010078467A - Method and System for using bi-fuel generator - Google Patents

Abstract

PURPOSE: A cogeneration system with a generator using both gas and gasoline is provided to use gas in normal operation, and gasoline in emergency with an emergency generator. CONSTITUTION: A cogeneration system is composed of an engine unit generating power with gas and gasoline, a generator for producing power by the engine unit, and a heat exchanger for generating steam and hot water by coolant and exhaust heat of the engine unit. The generator consists of a gas solenoid valve(20) supplying and shutting off gas according to operation of the generator, a pressure regulator(40) keeping constant pressure with adjusting gas flow, a gas regulating and mixing unit(60) controlling gas supply according to the load of the generator as well as mixing gas and gasoline, and a controller(100) stopping the engine in emergency and controlling the supply of gas and gasoline by detecting gas supply, temperature of exhaust gas and pressure of engine oil. The controller supplies power from the generator in emergency by detecting the power supply.

Description

Cogeneration system using gas / diesel generator and its operation method {Method and System for using bi-fuel generator}

The present invention relates to an emergency generator that is installed in a facility such as a building, a hospital, and more specifically, by using a generator that can be used for both city gas and diesel, power and heat can be performed at all times by operation and emergency power supply at the same time. The present invention relates to a cogeneration system using a gas / diesel generator.

Large facilities such as buildings and hospitals are equipped with generators used for emergency power in case of power supply cut off, and emergency generators are required to be installed in new buildings over a certain scale.

As such an emergency generator, a diesel generator that uses diesel fuel is usually used.

The diesel generators are to be shut down when the power is normally supplied, and then operate in an emergency situation in which the power supply is cut off from KEPCO.

However, unlike in the past, the situation in which power supply has been smoothed nowadays is significantly reduced, and thus, the case where a diesel generator has to be operated is decreasing.

Therefore, the diesel generators installed in each facility have a serious problem that the test operation is not performed properly, resulting in mechanical damage and defects, and because they are left unused for a long time, they do not operate properly in an emergency.

In addition, even if it is rarely used, the construction of the emergency generator must be installed at the time of construction, resulting in an increase in construction costs.

Therefore, it is necessary to develop a cogeneration system that can efficiently save energy by rationalizing the use of energy by efficiently operating an emergency generator that is necessary but is becoming obsolete.

Accordingly, the present invention was devised to meet the requirements as described above, by using an emergency generator that can be used for both city gas and diesel, the commercial power of the power consumption is obtained by using a cheap city gas Its purpose is to provide a cogeneration system using a combined gas / diesel generator that can serve as an emergency generator by operating via diesel in case the power or gas supply is cut off.

In addition, another object of the present invention is to provide a cogeneration system using a gas / diesel combined generator capable of producing hot water and steam using heat generated when the generator is operated.

1 is a schematic diagram showing a cogeneration system using a gas / diesel combined generator according to the present invention;

2 is a flowchart of a cogeneration system according to the present invention;

3 is a view showing the configuration of a gas / diesel combined generator according to the present invention,

4 is a view showing a gas control and mixing device in the generator according to the present invention,

5 is a view showing a pressure regulator in the generator according to the present invention,

6 is a schematic diagram illustrating a heat exchanger of a generator according to the present invention.

Explanation of symbols on the main parts of the drawings

10: gas / diesel combined generator 20: gas solenoid valve

40: pressure regulator 41: housing

42: plate 43: inlet

44: outlet 45: distribution hall

46: check valve 48: diaphragm

50: female screw 51: adjusting screw

53: guide bar 54: elastic spring

60: gas control and mixing device 70: exhaust gas temperature sensor

71: air pipe 72: choke valve

73: actuator 74: gas injection pipe

75: injection nozzle 100: controller

110: heat exchanger 114: water pipe group

115: hot water pipe

In order to achieve the above object, the cogeneration system of the present invention includes an engine unit capable of producing power by using both city gas and diesel fuel supplied to a building, and a power generation unit for producing electric power using the power of the engine unit; It comprises a heat exchanger for producing steam and hot water by using the coolant and exhaust heat of the engine unit.

The engine unit in the diesel engine, the gas solenoid valve for supplying / blocking the city gas in accordance with the operation of the engine, to maintain the pressure by changing the flow rate of the supply gas in accordance with the pressure change of the air inlet to the engine Pressure regulator, control of gas supply according to load increase and decrease of generator, gas control and mixing device for mixing air and gas for combustion, engine stop and city gas in emergency by detecting temperature of exhaust gas and pressure of engine oil And a controller for controlling the amount of gas so that the diesel oil can be supplied in an optimal state and for converting the generated power to commercial or emergency use.

The power generation unit is composed of a rotation field type synchronous generator for producing electric power by using the power of the engine main body.

The heat exchange unit is arranged in a heat exchange tube installed with a coolant inlet pipe and a discharge pipe so that the heated coolant flows through the engine, an exhaust pipe of the engine installed through the inside of the heat exchange cylinder, and a heat exchanger tube, so that water is cooled by heat of the coolant and exhaust gas It includes a water pipe group for heating the.

The operation of the cogeneration system having the above structure is divided into normal operation and emergency operation. The regular operation operates the generator at all times by using city gas supplied to the building, and the power and heat produced according to the generator operation are compared with the required power of the building. In case of emergency operation in which power supplied to the building or city gas is cut off, the generator is operated only by diesel to supply emergency power to the building.

In other words, the cogeneration operation system according to the present invention determines whether the city gas is supplied, and when the city gas is supplied, the combined operation step for operating the generator using the city gas and diesel gas and diesel gas when the city gas is blocked Diesel operation step to operate the generator by itself, determining the power supply after the operation of the generator, if the power supply is smoothly commercial operation step to cover the power produced by the generator operation as part of the supply power, the power supply is cut off In this case, the emergency operation step of converting the power produced according to the generator operation for emergency, and the step of producing hot water using the heat generated by the generator operation.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

First, the engine unit of the present invention, which can be used in combination with city gas and diesel, will be described below with reference to FIGS. 1, 2, 3, and 4.

The engine used in the generator 10 of the present invention is operated by a compression ignition method of compressing a mixed gas in which city gas is mixed and injecting fuel into a diesel engine using diesel.

That is, as shown in FIG. 3, the engine includes a high pressure and high pressure fuel in an engine body 150 including a combustion chamber, a fuel tank 80, a fuel pump 90, and high pressure high temperature air in the combustion chamber 151. It includes a fuel injection device, a supercharger or a preheating device for spraying in a spray state.

And as a device for using the city gas in the diesel engine, the gas solenoid valve 20 for supplying / blocking the gas in accordance with the operating state of the generator, the supply gas in accordance with the pressure change of the air inlet to the engine A pressure regulator 40 for changing the flow rate of the gas to maintain a constant pressure, a gas control and mixing device 60 for controlling the gas supply amount according to the increase or decrease of the load of the generator, and mixing air and city gas for combustion; It includes a controller 100 for detecting the supply state of the city gas, the temperature of the exhaust gas, the pressure of the engine oil to control the stop of the engine in the emergency and the supply amount of the city gas and diesel.

City gas is passed through the pressure regulator 40 according to the opening and closing operation of the gas solenoid valve 20 installed on one side of the distribution pipe entering the building and then introduced into the gas control and mixing device 60 and mixed with air to the combustion chamber of the engine ( 151).

Pressure regulator 40 is a device that can control the amount of city gas injected into the gas control and mixing device, the negative pressure applied to the air intake line of the engine increases as the load increases, so as to maintain a constant pressure The flow rate of the city gas increases, and as the load decreases, the negative pressure decreases, and the flow rate of the city gas decreases.

Gas control and mixing device 60 is to adjust the flow rate of the city gas introduced into the combustion chamber of the engine and to mix the air and the city gas evenly as shown in FIG. ) And a choke valve 72 for opening and closing the air pipe, a drive actuator 73 for opening and closing the choke valve connected to the rotary shaft of the choke valve from the outside of the air pipe, and a gas installed inside the air pipe connected to one side of the air pipe. The injection pipe 74 is formed at the tip of the gas injection pipe to include a nozzle hole for atomizing the gas.

The gas control and mixing device will be described in more detail with the inlet air control unit consisting of the drive actuator 73 and the choke valve 72 and the gas injection pipe 74 and the nozzle hole for mixing the inlet air and gas. It consists of a mixing unit consisting of, the operation principle receives the signal of the magnetic pickup to detect the number of revolutions in accordance with the load of the generator from the controller drive actuator 73 is operated to operate the choke valve 72 of the air inlet as an example If the load is increased, the above operation is performed in the same order as above, so that the amount of intake air is reduced by the choke valve 72 and the city gas is supplied by the increase in the negative pressure in the air pipe 71 to cover the load.

That is, the amount of city gas input is controlled to supply the same amount of heat in the engine combustion chamber as compared with the ratio of diesel oil serving as a catalyst according to the signal of the controller 100. In this case, the diesel oil also serves as a lubrication role and an auxiliary energy source to remove foreign matters stuck to the inner wall of the cylinder when only the city gas is burned.

The controller 100 senses whether the city gas is supplied, the temperature of the exhaust gas and the pressure of the engine oil so that the city gas and the diesel oil can be supplied in the most optimal state. As the pressure changes, the gas supply amount and the diesel oil supply amount are controlled.

In other words, the amount of diesel fuel burned together increases or decreases according to the change in the methane content of the city gas, and when the supply of city gas is cut off, only the diesel oil is injected to operate in the same way as the diesel engine so that the generator can operate normally. .

The gas injection pipe 74 is bent at a right angle from the center of the air pipe passing through the side of the air pipe 71 has a structure in which the tip is directed toward the air input direction, the tip is a conical shape and a plurality of conical inclined surface Two injection nozzles 75 are arranged.

Therefore, the city gas injected through the injection nozzle is sprayed into the air pipe 71 under the negative pressure and is uniformly mixed with the air flowing along the air pipe 71 to be supplied to the combustion chamber.

At this time, the pressure regulator 40 maintains a constant pressure in the city gas line by changing the city gas flow rate into the combustion chamber, as shown in FIG. It is installed in the chamber 41, the check valve 46 for opening and closing the city gas inlet 43 and outlet 44, the distribution hole 45 formed in the diaphragm connected to each chamber of the housing, the inlet side chamber It is connected to the check valve comprises a diaphragm 48 for opening the check valve at a constant pressure and pressure adjusting means for adjusting the pressure of the diaphragm.

The check valve 46 has a cone shape and is installed to be pushed open toward the outlet 44 side chamber, and the tip of the cone is connected to the center of the diaphragm 48 through a connection bar.

The pressure regulating means is a female screw pipe 50 penetrated from the upper center of the housing 41 to the inside, an adjusting screw 51 fitted with the female screw pipe and having a hole therein, and installed in the center of the diaphragm to the inner hole of the adjusting screw. The guide bar 53 is inserted, the elastic spring 54 is inserted into the guide bar and elastically placed between the diaphragm and the adjustment screw tip.

Therefore, when tightening or releasing the adjusting screw, the pressing force of the elastic spring is changed to adjust the pressure of the diaphragm.

In addition, the synchronous generator constituting the power generation unit is a motor starting method by the battery is connected to the rotating shaft of the engine and the generator and the armature rotates relatively to generate an alternating current of the same frequency as the rotation frequency, the synchronous speed in the normal operation state AC motor rotating in the

On the other hand, when looking at the heat exchanger, as shown in Figure 6 to produce hot water and steam by using the exhaust gas and engine heat discharged from the engine, the cooling water inlet pipe so that the cooling water heated while passing through the engine 150 The heat exchange cylinder 110 with the 111 and the discharge pipe 112, the exhaust pipe 113 of the engine installed through the inside of the heat exchange cylinder, arranged in the heat exchange cylinder to heat the water by the heat of the cooling water and exhaust gas It consists of a canal group 114 for.

The cooling water inlet pipe 111 and the discharge pipe 112 are respectively installed in the upper and lower heat exchange cylinder 110, and the cooling water heated while passing through the engine 150 is introduced into the heat exchange cylinder 110 to exit the exhaust pipe, 113 is installed on the bottom side, is installed in a spiral wound inside the heat exchange tube 110, the exhaust gas is passed through the exhaust pipe 113 has a structure in which the noise is reduced.

The water pipe group 114 is provided with a plurality of thin pipes through a heat exchange tube 110, and a hot water pipe 115 is installed at the tip of the water pipe group 114 so that the heat-exchanged hot water flows. Therefore, the cold water is introduced through the lower hot water pipe 115 is heated while passing through the water pipe group 114 in the heat exchange tube 110 is sent to the required place through the upper hot water pipe 115.

Here, referring to the flow of hot water in the cogeneration system consisting of the heat exchanger of the structure described above with reference to Figure 1, in the building separate boiler 120, the elevated tank 121, the low-temperature tank 122 is provided with an elevated tank The water of is heated in the boiler and is supplied to the hot water tank and then sent to each hot water use destination. The system supplies a part of the hot water supply through the heat exchange unit.

Therefore, a part of the water in the high-priced tank is heat-exchanged in the heat exchange tube 110 by the engine heat and the heat of the exhaust gas according to the operation of the generator 10 and is supplied to the low-temperature tank and then sent to the hot water usage place.

As the hot water is used, water is supplied to the water pipe group and the boiler to continuously produce hot water.

On the other hand, the operating method of the heat conversion power generation system including the engine unit, the power generation unit, the heat exchange unit as described above is as shown in FIG. The controller switches the relays at each step to control the device.

That is, a step 130 of determining whether the city gas is supplied, a combined operation step 131 for operating the generator using the city gas and diesel gas when the city gas is supplied, and only the diesel gas when the city gas is blocked A diesel operation step 132 for operating a generator, a step 133 of determining whether power is supplied after the generator is started, and a commercial operation step of supplying the power produced according to the generator operation as part of the supply power when the power supply is smoothly performed ( 134), an emergency operation step 135 for converting the power produced according to the generator operation to the emergency when the power supply is cut off, and a step 136 of producing hot water using heat generated according to the generator operation.

In the determination step 130, the controller 100 turns on / off the solenoid valve 20 and controls the amount of diesel oil supplied through the fuel pump 90 according to the city gas supply, and operates only via the generator 10. It can be operated either in combination with the gas or city gas.

In the next judging step 133, the controller switches the relay according to whether power is supplied from KEPCO, so as to cover the power produced by the generator for commercial use or for emergency use.

Hereinafter will be described the operation of the present invention.

When the city gas is normally supplied, the controller switches the generator to the combined operation stage and operates the generator using the city gas and diesel.

The supplied city gas is mixed with air while passing through the gas solenoid valve 20, the pressure regulator, and the gas control and mixing device 60, and is supplied to the combustion chamber.

That is, when the generator is operated, the gas solenoid valve 20 is opened in response to a signal from the controller to send the city gas to the pressure regulator 40.

The city gas introduced through the inlet 43 of the pressure regulator 40 is discharged to the outlet at a constant pressure according to the pressure difference between the chamber of the inlet 43 and the outlet 44 of the chamber divided by the diaphragm 42. When the pressure in each chamber is the same, the check valve 46 connected to the diaphragm 48 is pulled to close the distribution hole 45 of the diaphragm to block the distribution of city gas, and the pressure in the outlet side chamber is lowered. Therefore, the check valve is gradually opened to distribute the city gas through the outlet.

Here, the check valve is pulled into the outlet side chamber according to the amount of pressure reduction (change) of the outlet side chamber, and the opening amount thereof is changed, thereby changing the discharge flow rate of the city gas to maintain a constant pressure.

The city gas passing through the outlet of the pressure regulator 40 is supplied to the correct gas amount through the gas injection pipe 74, injected through the injection nozzle is mixed with air and then supplied to the combustion chamber.

Here, the actuator 73 is operated in accordance with the signal of the controller according to the load increase and decrease of the generator to adjust the opening and closing amount of the choke valve 72, thereby adjusting the amount of air sucked.

Looking at the operation of the gas control and mixing device 60, the city gas is supplied to the gas injection pipe connected to the pressure regulator is sprayed in the form of a spray through the injection nozzle installed at the tip of the gas injection pipe, the gas injection pipe The air flowing into the installed air pipe is evenly mixed with the city gas sprayed through the injection nozzle and supplied to the combustion chamber of the engine.

The amount of air introduced into the air pipe 71 is controlled by an actuator controlled by the controller. When the actuator is operated to rotate the choke valve's rotary shaft, the choke valve's opening degree is changed and the amount of air supplied is adjusted as the opening and closing amount of the air pipe is adjusted, and the pressure regulator 40 according to the change in the negative pressure in the air pipe. The amount of city gas flowing through is also controlled.

The city gas mixed with air is finally supplied to the combustion chamber of the engine and compressed according to the stroke of the crank, and according to the signal of the controller, at least light oil is supplied to the combustion chamber by the fuel pump 90 to compress and mix the city gas and air. It will ignite the gas.

Here, the diesel fuel supplied to the combustion chamber plays a ignition role with a minimum amount. When the load of the engine increases, the supply of city gas increases instead of the diesel, and the city gas reaches up to about 95% of the maximum diesel consumption in comparison to when operating by diesel. It can be replaced with

The power produced according to the operation of the generator as described above is used for commercial or emergency use, the controller determines whether the power supplied to the building is normally supplied, if the power is normally supplied to the commercial power generated by the generator The power is supplied, and in the event of a power failure, the power produced by the generator is used for emergency use.

On the other hand, when the supply of city gas is cut off, the controller switches the generator to the diesel driving stage to operate the generator by diesel.

That is, the gas solenoid valve 20 is cut off in response to a signal from the controller, so that only air is supplied to the combustion chamber through the air pipe, thereby compressing the air in the same way as a normal diesel engine, thereby increasing the supply of diesel oil by the fuel pump. Ignition by diesel oil is generated and the equipment is continuously operated.

As described above, the generator 10 of the present invention is commercially available in addition to the emergency, and in particular, it is possible to use electric power at a lower cost than the electric charge by operating the city gas at a time when the electric charge is expensive.

On the other hand, cogeneration operation with the boiler in the building is possible according to the generator operation.

The water supplied to the elevated tank 121 in the building is supplied to the boiler 120 and the heat exchanger 110 is heated and sent to the storage tank 122, and is sent to each hot water use place in the storage tank.

That is, the water supplied to the high-priced tank is heat-exchanged by the engine heat and the exhaust gas heat generated by the operation of the generator while being distributed along the water pipe group 114 inside the heat exchange tube 110 through the hot water pipe 115, The heated hot water is sent to a storage tank, and is supplied to each hot water use place from the storage tank.

Some of the hot water supplied to the hot water usage area is discharged to the drainage line after being used, and the remaining hot water is reduced in temperature, and is then sent to the water pipe group along the connection line between the elevated tank and the hot water pipe to be reheated.

As hot water is used, the expensive tank is filled with water, and the water in the elevated tank is continuously supplied to the water pipe group and the boiler to continuously produce hot water.

The present invention can be seen to provide a cogeneration system having a significantly innovative operation as described above. While exemplary embodiments of the present invention have been shown and described, various modifications and other embodiments may be made by those skilled in the art. Such modifications and other embodiments are all considered and included in the appended claims, without departing from the true spirit and scope of the invention.

According to the cogeneration system using a gas / diesel combined generator according to the present invention as described above, by using a cheap city gas to produce a portion of the power itself, it is possible to reduce the cost paid by the power usage fee.

In addition, each building can supply a certain amount of power by itself, thereby reducing the need for power generation facilities and reducing the cost of construction.

In addition, by using the city gas it is possible to conserve the environment by minimizing the emission of air pollutants.

In addition, by allowing the city gas to be used as fuel for the engine in parallel with the diesel, it is possible to reduce the use of expensive diesel oil to produce electricity at low cost.

In addition, it is possible to maximize energy efficiency by producing hot water using the engine coolant and the heat of the exhaust gas.

In addition, there is an advantage that the installation structure is simple, the initial installation cost is low, and the operating cost is low and can be efficiently operated.

Claims (6)

In order to use the city gas in diesel engines and diesel engines, the gas solenoid valve for supplying / blocking the city gas in accordance with the operation of the engine, and the flow rate of the supply gas is changed in accordance with the pressure change of the air inlet to the engine. Pressure regulator to keep pressure constant, control gas supply according to load increase and decrease of generator, gas control and mixing device to mix air and gas for combustion, use of city gas and diesel oil supply and power generated A power generation unit including a controller for controlling a state and a rotation field type synchronous generator for producing electric power using power of the engine main body; Heat exchanger for producing steam and hot water using the coolant and exhaust heat of the engine unit; Cogeneration system using a combined gas / diesel generator comprising a. The heat exchanger of claim 1, wherein the heat exchanger is arranged in a heat exchange tube provided with a coolant inlet pipe and a discharge pipe so as to distribute the coolant heated through the engine, an exhaust pipe of the engine installed inside the heat exchange tube, and a heat exchanger cylinder. A cogeneration system using a combined gas / diesel generator, comprising: a water pipe group for heating water by heat of exhaust gas; and a hot water pipe connected to a distal end of the water pipe group to distribute cold water and hot water to the water pipe group. According to claim 1, wherein the gas regulating and mixing device is an air pipe through which the air flows, the choke valve for opening and closing the air pipe, the drive actuator connected to the rotary shaft of the choke valve outside the air pipe for opening and closing the choke valve, A cogeneration system using a gas / diesel combined generator comprising a gas injection pipe connected to one side of the air pipe and installed in the air pipe, and a nozzle hole formed at the tip of the gas injection pipe to spray gas. The pressure regulator of claim 1, wherein the pressure regulator is provided with a diaphragm housing therein to form a dual structure, the city gas inlet and outlet, which is connected to each chamber of the housing, check valve for opening and closing the distribution hole formed in the diaphragm, inlet A cogeneration system using a gas / diesel combined generator, which is installed in the side chamber and connected to the check valve, the diaphragm for opening the check valve at a constant pressure and pressure adjusting means for adjusting the pressure of the diaphragm. 5. The pressure adjusting means of claim 4, wherein the pressure adjusting means includes a female screw pipe penetrating from the upper center of the housing to the inside, an adjustment screw fitted to the female screw pipe, and having an inner hole formed therein, and inserted into the adjusting screw inner hole in the center of the diaphragm. A cogeneration system using a combined gas / diesel generator, comprising a guide bar and an elastic spring inserted into the guide bar and elastically placed between the diaphragm and the adjustment screw tip. Determining whether the city gas is supplied; A combined operation step for operating a generator using city gas and diesel when city gas is supplied; A diesel operation step for operating the generator by diesel only when the city gas is blocked; Determining whether power is supplied after the generator is operated; A commercial operation step of supplying the power produced according to the generator operation as a part of the supply power when the power supply is performed smoothly; Emergency operation step of switching the power produced according to the generator operation for emergency when the power supply is cut off; Producing hot water using heat generated according to the operation of the generator; Cogeneration system operating method using a combined gas / diesel generator comprising a.