JP2005337046A - Gas engine equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas engine device that adjusts a combustible range of an air-fuel mixture and burns under optimum conditions.
In a gas engine device (1), gas fuel and an oxidant and a part of engine exhaust gas are supplied into a cylinder, and an air-fuel mixture compressed in the cylinder is ignited by an ignition device (4). Temperature detection means 5 for detecting the end-of-compression temperature, exhaust gas circulation rate detection means for detecting the exhaust gas circulation rate when a part of the exhaust gas of the engine is circulated in the cylinder, and exhaust gas circulation for adjusting the exhaust gas circulation rate The rate adjusting means 9 and the control means 14 for controlling the exhaust gas circulation rate adjusting means are provided, and the control means is set to increase the exhaust gas circulation rate as the detected temperature increases.
[Selection] Figure 1

Description

  The present invention relates to a gas engine, and more particularly to a pilot ignition gas engine apparatus.

  As this type of gas engine, one disclosed in Patent Document 1 is known.

  The engine of Patent Document 1 is filled with a premixed mixture of gas fuel and air into a cylinder, and injects diesel fuel with good ignitability from a nozzle during a compression stroke to ignite the premixed mixture. Yes.

  In the engine disclosed in Patent Document 1, an ignition diesel fuel nozzle is provided in the vicinity of a suction valve of a cylinder head, and a gas fuel injection nozzle is provided on a cylinder wall. In such an engine of Patent Document 1, a gas fuel injection nozzle that injects gas fuel into the air sucked into the cylinder at an appropriate time between the late stage of the intake stroke and the late stage of the compression stroke faces the cylinder from the cylinder wall. According to Patent Document 1, since only air is sucked into the cylinder during the intake stroke, the amount of air sucked into the cylinder can be increased, and therefore the engine output can be improved. It is supposed to be possible.

As a measure for reducing nitrogen oxides in exhaust gas, Patent Document 2 discloses a recirculation gas engine that recirculates a part of exhaust gas from an engine to an intake system. The thing of this patent document 2 reduces the oxygen concentration in air-fuel | gaseous mixture by recirculating waste gas to an intake system, and reduces the quantity of the nitrogen oxide produced | generated.
JP-A-6-137150 JP 10-141144 A

  However, the gas engine of Patent Document 1 that injects liquid fuel as an ignition source is required to be improved in the following points.

  First, it is common to not only gas engines but also other types of engines. However, in the case of an engine that injects liquid fuel as an ignition source, if the temperature of the combustion gas is low, the above-mentioned ignition is performed. The temperature of the liquid fuel injected as a fire source is lowered by the heat of vaporization, and it is difficult to ignite particularly at the time of starting. As a matter of course, increasing the intake air temperature decreases volumetric efficiency.

  Further, since the ignition fuel is a liquid fuel, the combustion time is relatively long and a large amount of unreacted substances such as soot tend to be discharged.

  Furthermore, when the excess air ratio is lowered, the amount of nitrogen oxide emissions increases.

  Moreover, in the gas engine of patent document 2, the fuel, the air-fuel mixture of air and the recirculated exhaust gas may not be burned under the optimum combustible range. Specifically, when starting the engine or part-loading, or using gas whose fuel composition or amount is variable, such as gas generated from sludge digestion gas or waste pyrolysis When the operating state of the engine fluctuates like this, a large amount of harmful substances such as nitrogen oxides and unburned components may be discharged into the exhaust gas. Also, the output efficiency is greatly reduced during partial load operation.

  In view of these points, the present invention adjusts the combustible range of the air-fuel mixture according to the operating state of the engine and burns under optimum conditions, has good ignitability, high thermal efficiency, and reduction of nitrogen oxide emission concentration. An object of the present invention is to provide a pilot ignition type gas engine device that enables the above.

  A gas engine apparatus according to the present invention supplies gas fuel, an oxidant, and a part of engine exhaust gas into a cylinder, and ignites an air-fuel mixture compressed in the cylinder by an ignition device.

  In such a gas engine device, the above object is achieved by any one of the first to sixth inventions having the following characteristics.

<First invention>
Adjusting the exhaust gas circulation rate, temperature detection means for detecting the end-of-compression temperature of the air-fuel mixture in the cylinder, exhaust gas circulation rate detection means for detecting the exhaust gas circulation rate when part of the engine exhaust gas is circulated in the cylinder Exhaust gas circulation rate adjusting means and control means for controlling the exhaust gas circulation rate adjusting means, the control means being set to increase the exhaust gas circulation rate as the detected temperature rises.

<Second invention>
Detection of at least one of temperature detection means for detecting the end-of-compression temperature of the air-fuel mixture in the cylinder and exhaust gas circulation rate detection means for detecting the exhaust gas circulation rate when part of the engine exhaust gas is circulated in the cylinder And a control means for controlling the ignition device, and the control means is set to reduce the ignition energy of the ignition device in accordance with at least one of an increase in the detected temperature and a decrease in the detected exhaust gas circulation rate.

<Third invention>
At least one of a temperature detecting means for detecting the end-of-compression temperature of the air-fuel mixture in the cylinder and an exhaust gas circulation rate detecting means for detecting an exhaust gas circulation rate when a part of the exhaust gas of the engine is circulated in the cylinder And control means for controlling the pressure of the air-fuel mixture at the cylinder inlet, so that the control means reduces the pressure of the air-fuel mixture at the cylinder inlet as at least one of an increase in the detected temperature and a decrease in the detected exhaust gas circulation rate. Is set to

<Fourth Invention>
Adjusting the exhaust gas circulation rate, temperature detection means for detecting the end-of-compression temperature of the air-fuel mixture in the cylinder, exhaust gas circulation rate detection means for detecting the exhaust gas circulation rate when part of the engine exhaust gas is circulated in the cylinder Exhaust gas circulation rate adjusting means, control means for controlling the exhaust gas circulation rate adjusting means and the ignition device, the control means increases the exhaust gas circulation rate as the detection temperature rises, The ignition energy of the ignition device is set to be reduced with at least one of the reductions in the circulation rate.

<Fifth invention>
Adjusting the exhaust gas circulation rate, temperature detection means for detecting the end-of-compression temperature of the air-fuel mixture in the cylinder, exhaust gas circulation rate detection means for detecting the exhaust gas circulation rate when part of the engine exhaust gas is circulated in the cylinder Exhaust gas circulation rate adjusting means, and an exhaust gas circulation rate adjusting means and a control means for controlling the pressure at the cylinder inlet. The control means increases the exhaust gas circulation rate as the detection temperature increases, and increases the detection temperature. It is set so that the pressure of the air-fuel mixture at the cylinder inlet is lowered with at least one of the reductions in the detected exhaust gas circulation rate.

<Sixth Invention>
Adjusting the exhaust gas circulation rate, temperature detection means for detecting the end-of-compression temperature of the air-fuel mixture in the cylinder, exhaust gas circulation rate detection means for detecting the exhaust gas circulation rate when part of the engine exhaust gas is circulated in the cylinder An exhaust gas circulation rate adjusting means, an exhaust gas circulation rate adjusting means, an ignition device, and a control means for controlling the pressure of the air-fuel mixture at the cylinder inlet, and the control means increases the exhaust gas circulation rate as the detected temperature rises. The ignition energy of the ignition device is reduced and the pressure of the air-fuel mixture at the cylinder inlet is reduced with at least one of an increase in the detected temperature and a decrease in the detected exhaust gas circulation rate.

  In the above first to sixth inventions, the end-of-compression temperature of the air-fuel mixture in the cylinder and the exhaust gas circulation rate are detected, and based on these detected values, the exhaust gas circulation rate, ignition energy, and the pressure of the air-fuel mixture at the cylinder inlet are detected. Either or at least one of the ignition energy and the pressure of the air-fuel mixture at the cylinder inlet is controlled in addition to the exhaust gas circulation rate, and by these controls, an optimum adjustment is made in response to fluctuations in the operating state of the gas engine The following advantages are brought about.

(1) Adjustment of exhaust gas circulation rate If the exhaust gas circulation rate is higher than the appropriate range, nitrogen oxides can be reduced, but stable combustion may not be achieved. Moreover, when low, generation | occurrence | production of a nitrogen oxide cannot be suppressed. Therefore, if the exhaust gas circulation rate is brought to an appropriate range, stable combustion can be performed without knocking while keeping the oxygen concentration in the cylinder low, lowering the flame temperature and reducing nitrogen oxides, so high compression ratio operation can be performed, As a result, the thermal efficiency is good. For example, when power is generated by an engine, high-efficiency power generation is possible.

  Furthermore, by optimizing the exhaust gas circulation rate, the partial load performance of the engine is improved, abnormal combustion is prevented, and the durability of the engine is improved.

(2) Adjustment of ignition energy By appropriately adjusting the ignition energy, it is possible to shorten the warm-up operation time, prevent misfiring and abnormal combustion, and the like. Shortening the warm-up time results in fuel savings, and preventing abnormal combustion reduces pollution and improves engine durability.

(3) Adjustment of the pressure of the air-fuel mixture at the cylinder inlet The pressure of the air-fuel mixture at the cylinder inlet can be appropriately adjusted by adjusting the auxiliary motor output of the supercharger, for example. By adjusting the pressure, the temperature at the end of compression of the air-fuel mixture in the cylinder is optimized, and a high compression ratio, prevention of pre-ignition in the compression stroke, and stabilization of combustion in the explosion stroke are obtained. High compression ratio operation improves thermal efficiency and enables high-efficiency power generation. By preventing pre-ignition during the compression stroke, low pollution can be achieved, and depending on stable combustion during the explosion stroke, high-efficiency power generation and low pollution can be achieved.

  In the control according to the above-described invention, increasing the exhaust gas circulation rate as the detected temperature increases means, in other words, reducing the exhaust gas circulation rate when the detected temperature decreases. For example, the exhaust gas circulation rate is increased or decreased by adjusting the opening of the valve in the circulation path.

  Next, as the detected temperature rises and the detected exhaust gas circulation rate decreases, the ignition energy is reduced and the pressure of the air-fuel mixture at the cylinder inlet is reduced. When the rate increases, it also means that the ignition energy is increased and the pressure of the air-fuel mixture at the cylinder inlet is increased. The ignition energy can be increased or decreased by adjusting the fuel injected by the ignition device, and the pressure of the air-fuel mixture at the cylinder inlet can be increased or decreased by adjusting the output of the auxiliary motor of the turbocharger and adjusting the pressure at the pressurizing unit. The

  As described above, according to the present invention, by adjusting the exhaust gas circulation rate, the ignition energy, and the pressure of the air-fuel mixture at the cylinder inlet, the compressed air-fuel mixture in the cylinder is ignited in an appropriate range. It is low pollution and knocking is suppressed, and high thermal efficiency can be obtained under high compression ratio operation. Furthermore, as a result of the optimized combustion range, it is possible to mix a part of the engine exhaust gas into the air-fuel mixture, achieve a high exhaust gas circulation rate, reduce nitrogen oxide emissions and internal heat circulation To obtain high thermal efficiency.

  Furthermore, as a result of the uniform combustion in the cylinder, combustion control becomes easy, the engine structure can be simplified, durability can be improved, and equipment costs can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  In FIG. 1, reference numeral 1 denotes a gas engine in the present embodiment. In FIG. 1, in particular, illustration of a cylinder and a piston is omitted. The preferred embodiment has a supercharger 2 as a preferred form, and its driven portion 2A is connected to the exhaust side 1A of the engine 1 and the pressurizing portion 2B is connected to the intake side 1B of the engine 1. The supercharger 2 is driven to rotate by the exhaust of the engine 1 and compresses intake air, which will be described later, in the pressurizing unit 2B and supplies the compressed air into the cylinder of the engine 1. The supercharger 2 is connected to an auxiliary motor 3 that assists driving by exhaust gas. The cylinder of the engine 1 is equipped with an ignition device 4 and a temperature sensor 5 as temperature detecting means for detecting the temperature of the air-fuel mixture. As a temperature sensor, a radiation thermometer is used to detect the temperature of the air-fuel mixture in the cylinder through a window. Alternatively, a thermocouple may be installed on the inner wall of the cylinder, and the relationship between the detection value by the thermocouple and the mixture temperature may be obtained in advance to serve as temperature detection means.

  The exhaust side 1 </ b> A of the engine 1 is connected to an exhaust gas treatment device 7 through a connecting pipe 6. The connection pipe 6 is branched in the middle, and an exhaust gas circulation path 8 is provided to join with the downstream side of the pressurizing unit 2 </ b> B of the supercharger 2. The exhaust gas of the engine 1 is brought to the exhaust gas treatment device 7 after driving the driven part 2A of the supercharger 2, but a part of the exhaust gas flows to the circulation path 8. The circulation path 8 is provided with a circulation rate adjusting means 9 for adjusting the exhaust gas circulation rate. The circulation rate adjusting means 9 is, for example, an on-off valve whose opening degree can be adjusted. Here, the exhaust gas circulation rate refers to the ratio of the circulating exhaust gas amount to the total exhaust gas amount discharged from the engine. The exhaust gas circulation rate is detected by measuring the total exhaust gas amount and the circulating exhaust gas amount with flow meters provided in the respective flow paths. The flow rate of the air-fuel mixture sent to the cylinder, that is, the intake air, gaseous fuel, and circulating exhaust gas sent to the cylinder is measured with a flow meter, and the amount of circulating exhaust gas relative to the total total amount (A) of the air-fuel mixture. The ratio (B / A) of (B) may be obtained and adjusted based on the value of B / A.

  An intake pipe 10 for taking in air as an oxidant from the outside is provided in the pressurizing unit 2B of the supercharger 2, and gaseous fuel is supplied to an intake line 11 connecting the pressurizing unit 2B and the intake side 1B of the engine. A source 12 and an exhaust gas circulation path 8 are connected. The gaseous fuel supply source 12 is also connected to the ignition device 4 via a fuel flow rate adjusting device 13 so as to supply gaseous fuel as ignition fuel in the ignition device 4.

  The apparatus according to the present embodiment also includes a control device 14. The control device 14 is connected to the exhaust gas circulation rate adjusting means 9, the fuel flow rate adjusting device 13 for the ignition device 4, and the auxiliary motor 3 of the supercharger 2 so as to be appropriately controllable.

  In this embodiment of the apparatus, the intake air is pressurized by the pressurizing part of the supercharger 2 that is driven by exhaust gas on the exhaust side 1A of the engine 1 and rotated by exhaust gas, and is sent to the intake line 11. .

  Gaseous fuel and a part of the engine exhaust gas are fed into the intake line 11 from the gaseous fuel supply source 12 via the circulation path 8 and mixed with the pressurized air, and from the intake side of the engine 1 into the cylinder. Supplied as a mixture.

  This air-fuel mixture burns the air-fuel mixture by injection and ignition of gaseous fuel in the ignition device 4 to drive the engine 1. It is preferable to use a device for injecting ultra-high temperature plasma as the ignition device 4. The ignition device 4 intermittently burns a mixture of gaseous fuel and oxidant, generates ultra-high temperature plasma by detonation, and injects the plasma into the cylinder at the timing when the mixture in the cylinder is ignited. And ignite the mixture. Since the principle of detonation itself is known, the invention is omitted here. In the ignition device that generates plasma by detonation, if the cross-sectional area of the flow is converged from the detonation chamber toward the plasma injection nozzle, higher temperature plasma is obtained. Since the plasma is ejected in a plurality of directions, for example, radially, the air-fuel mixture in the cylinder is ignited in a wide range, and as a result, combustion is performed uniformly. As an ignition device, the air-fuel mixture in the cylinder may be ignited by combustion of gaseous fuel and oxidant without generating plasma.

  In the present embodiment, the control device 14 can selectively control the gas engine device in the following six modes (I) to (VI).

(I) Control of exhaust gas circulation rate The higher the mixture temperature at the end of compression, the more the fuel can be combusted even if the fuel concentration is low. That is, combustion is possible even if the exhaust gas circulation rate is increased, and the generated nitrogen oxides can be reduced by reducing the oxygen concentration in the air-fuel mixture while ensuring stable combustion. From this point of view, the temperature detection means detects the mixture temperature at the end of compression, and if the detected temperature is high, the exhaust gas circulation rate is increased accordingly. On the contrary, when the detected temperature is low, the exhaust gas circulation rate is lowered.

(II) Control of ignition energy The higher the temperature at the end of compression and the higher the oxygen concentration, that is, the lower the exhaust gas circulation rate, the easier the ignition of the air-fuel mixture. Therefore, the ignition energy is controlled by adjusting either the detected temperature at the end of compression or the detected exhaust gas circulation rate. Specifically, when the detected temperature at the end of compression is low or the detected exhaust gas circulation rate is high, the supply amount of gaseous fuel for ignition is increased. Conversely, when the temperature at the end of compression is high, or the detected exhaust gas When the circulation rate is low, the supply amount of gaseous fuel for ignition is decreased.

  In the case of this mode of control, the degree of the influence of both on the extent to which the ignition energy should be controlled by the detected temperature at the end of compression and the detected exhaust gas circulation rate is generally as follows.

  That is, when the detected temperature at the end of compression is high and the exhaust gas circulation rate is high, the ignition energy may be slightly lower, but when the exhaust gas circulation rate is low, the ignition energy may be significantly low. On the contrary, when the detected temperature at the end of compression is low and the exhaust gas circulation rate is high, the ignition energy may be significantly increased, and when the exhaust gas circulation rate is low, the ignition energy may be set slightly higher.

(III) Control of the pressure of the air-fuel mixture at the cylinder inlet The air-fuel mixture is more easily ignited as the temperature at the end of compression is higher and the oxygen concentration is higher, as extended in (II) above. Therefore, the pressure of the air-fuel mixture at the cylinder inlet may be adjusted by detecting either the detected temperature at the end of compression or the detected exhaust gas circulation rate. Specifically, when the detected temperature at the end of compression is low or when the detected exhaust gas circulation rate is high, the pressure of the air-fuel mixture at the cylinder inlet is increased. Conversely, when the temperature at the end of compression is high or when the detected exhaust gas circulation is detected When the rate is low, the pressure of the air-fuel mixture at the cylinder inlet is reduced. The increase or decrease of the pressure of the air-fuel mixture at the cylinder inlet can be performed by operating the auxiliary motor or brake of the supercharger.

  In the case of this mode of control, the degree of the influence of both on the degree to which the pressure of the air-fuel mixture at the cylinder inlet should be controlled by the detected temperature at the end of compression and the detected exhaust gas circulation rate is generally as follows. .

  That is, when the detected temperature at the end of compression is high and the exhaust gas circulation rate is high, the mixture pressure at the cylinder inlet may be slightly lower, but when the exhaust gas circulation rate is low, the pressure at the cylinder inlet mixture may be significantly low. Good. On the contrary, when the detected temperature at the end of compression is low and the exhaust gas circulation rate is high, the pressure of the air-fuel mixture at the cylinder inlet is greatly increased, and when the exhaust gas circulation rate is low, the air-fuel mixture at the cylinder inlet is The pressure may be set slightly higher.

(IV) Simultaneous control of exhaust gas circulation rate and ignition energy In this mode, the exhaust gas circulation rate of (I) and the ignition energy of (II) are controlled together. That is, the exhaust gas circulation rate is controlled by the detected temperature at the end of compression of the air-fuel mixture, and the ignition energy is controlled by at least one of the detected temperature and the detected exhaust gas circulation rate.

(V) Simultaneous control of exhaust gas circulation rate and pressure of air-fuel mixture at cylinder inlet In this mode, the exhaust gas circulation rate by (I) and the pressure of air-fuel mixture at the cylinder inlet by (III) are controlled together. That is, the exhaust gas circulation rate is controlled by the detected temperature at the end of compression of the air-fuel mixture, and the air-fuel mixture pressure at the cylinder inlet is controlled by at least one of the detected temperature and the detected exhaust gas circulation rate.

(VI) Simultaneous control of exhaust gas circulation rate, ignition energy and pressure of air-fuel mixture at cylinder inlet In this mode, exhaust gas circulation rate by (I), ignition energy by (II) and mixing at cylinder inlet by (III) It controls together with the air pressure. That is, the exhaust gas circulation rate is controlled by the detected temperature at the end of compression of the air-fuel mixture, and the ignition energy and the pressure of the air-fuel mixture at the cylinder inlet are controlled by at least one of the detected temperature and the detected exhaust gas circulation rate.

  The air-fuel mixture temperature at the end of compression fluctuates when starting the gas engine or during partial load operation as compared to during rated operation, and also fluctuates with variations in the composition and supply amount of gaseous fuel supplied to the gas engine. By detecting such a change in the mixture temperature at the end of compression and adjusting the exhaust gas circulation rate, ignition energy, and the pressure of the mixture gas at the cylinder inlet as described above, stable and efficient thermal efficiency is achieved. A high gas engine can be operated.

  Instead of detecting and controlling the temperature of the air-fuel mixture at the end of compression, the oxygen concentration or CO concentration in the exhaust gas from the engine may be detected and controlled. Control is performed to increase the exhaust gas circulation rate as the oxygen concentration increases. Since the increase in the CO concentration indicates that the combustion in the cylinder is unstable, the exhaust gas circulation rate is lowered, the ignition energy is increased, and the pressure of the air-fuel mixture at the cylinder inlet is increased.

  In the above embodiment, an air-fuel mixture of gaseous fuel and oxidant is intermittently burned to generate ultra-high temperature plasma by detonation, and this ultra-high temperature plasma is injected into the cylinder to ignite. Yes. In addition to this method, liquid fuel may be injected to ignite. In this case, the ignition energy is adjusted by adjusting the amount of liquid fuel supplied.

  Gaseous fuel and air are supplied into the engine cylinder at a ratio of excess air ratio of 1.2 to 1.3, and the exhaust gas is mixed at an exhaust gas circulation rate of 40%. The engine is operated under the condition that the mixture temperature at the end of compression is 950 to 1000 ° C., the ignition energy is 1% of the total input energy, and the temperature of the mixture at the end of compression is detected according to the present invention. The circulation rate was adjusted. As a result, the nitrogen oxide content in the exhaust gas was about 95 ppm even during partial load operation and when the composition and supply amount of the supplied gas fuel were varied, and generation could be significantly suppressed.

It is a schematic block diagram of the apparatus of 1st embodiment of this invention.

Explanation of symbols

1 Gas engine (device)
4 Ignition device 5 Temperature detection means (sensor)
9 Exhaust gas circulation rate adjustment means

Claims (6)

  In a gas engine device that supplies gas fuel and oxidant and a part of engine exhaust gas into a cylinder and ignites the mixture compressed in the cylinder by an ignition device, the compression end temperature of the mixture in the cylinder is reduced. Temperature detecting means for detecting, exhaust gas circulation rate detecting means for detecting an exhaust gas circulation rate when a part of engine exhaust gas is circulated in the cylinder, exhaust gas circulation rate adjusting means for adjusting the exhaust gas circulation rate, exhaust gas circulation And a control means for controlling the rate adjusting means, wherein the control means is set to increase the exhaust gas circulation rate as the detected temperature rises.   In a gas engine device that supplies gas fuel and oxidant and a part of engine exhaust gas into a cylinder and ignites the mixture compressed in the cylinder by an ignition device, the compression end temperature of the mixture in the cylinder is reduced. At least one detection means of temperature detection means for detecting and exhaust gas circulation rate detection means for detecting an exhaust gas circulation rate when a part of the exhaust gas of the engine is circulated in the cylinder, and control means for controlling the ignition device And the control means is set to reduce the ignition energy of the ignition device in accordance with at least one of an increase in the detected temperature and a decrease in the detected exhaust gas circulation rate.   In a gas engine device that supplies gas fuel and oxidant and a part of engine exhaust gas into a cylinder and ignites the mixture compressed in the cylinder by an ignition device, the compression end temperature of the mixture in the cylinder is reduced. Detecting at least one of temperature detecting means for detecting and exhaust gas circulation rate detecting means for detecting an exhaust gas circulation rate when a part of engine exhaust gas is circulated in the cylinder; And a control means for controlling, wherein the control means is set so as to reduce the pressure of the air-fuel mixture at the cylinder inlet in accordance with at least one of an increase in the detected temperature and a decrease in the detected exhaust gas circulation rate. Gas engine device.   In a gas engine device that supplies gas fuel and oxidant and a part of engine exhaust gas into a cylinder and ignites the mixture compressed in the cylinder by an ignition device, the compression end temperature of the mixture in the cylinder is reduced. Temperature detecting means for detecting, exhaust gas circulation rate detecting means for detecting an exhaust gas circulation rate when a part of engine exhaust gas is circulated in the cylinder, exhaust gas circulation rate adjusting means for adjusting the exhaust gas circulation rate, exhaust gas circulation A rate adjusting means and a control means for controlling the ignition device, the control means increasing the exhaust gas circulation rate as the detected temperature increases, and at least one of increasing the detected temperature and decreasing the detected exhaust gas circulation rate. A gas engine device that is set to reduce ignition energy of an ignition device.   In a gas engine device that supplies gas fuel and oxidant and a part of engine exhaust gas into a cylinder and ignites the mixture compressed in the cylinder by an ignition device, the compression end temperature of the mixture in the cylinder is reduced. Temperature detecting means for detecting, exhaust gas circulation rate detecting means for detecting an exhaust gas circulation rate when a part of engine exhaust gas is circulated in the cylinder, exhaust gas circulation rate adjusting means for adjusting the exhaust gas circulation rate, exhaust gas circulation A rate adjusting means and a control means for controlling the pressure at the cylinder inlet. The control means increases the exhaust gas circulation rate as the detected temperature rises, and at least one of increasing the detected temperature and decreasing the detected exhaust gas circulation rate. Accordingly, the gas engine device is set so as to reduce the pressure of the air-fuel mixture at the cylinder inlet. In a gas engine device that supplies gas fuel and oxidant and a part of engine exhaust gas into a cylinder and ignites the mixture compressed in the cylinder by an ignition device, the compression end temperature of the mixture in the cylinder is reduced. Temperature detecting means for detecting, exhaust gas circulation rate detecting means for detecting an exhaust gas circulation rate when a part of engine exhaust gas is circulated in the cylinder, exhaust gas circulation rate adjusting means for adjusting the exhaust gas circulation rate, exhaust gas circulation A rate adjusting means, an ignition device, and a control means for controlling the pressure of the air-fuel mixture at the cylinder inlet. The control means increases the exhaust gas circulation rate as the detection temperature increases, and increases the detected temperature and the detected exhaust gas circulation rate. Is set to reduce the ignition energy of the ignition device and to reduce the pressure of the air-fuel mixture at the cylinder inlet with at least one of the reductions of Gas engine arrangement according to symptoms.

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