JP2010242739A - Ignition system for gas engine, gas engine having the ignition system and method for driving the gas engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition system for a gas engine, the gas engine having the ignition system and a method for driving the gas engine, for achieving operational reliability of the gas engine or safety against failure. <P>SOLUTION: In the ignition system for the gas engine, the gas engine having the ignition system and the method for driving the gas engine, the ignition system has an injection device for injecting an ignition gas flow with a fuel has mixture as a base into a pre-combustion chamber of a cylinder of a gas engine, and an ignition trigger device composing an igniter based on heat. The igniter based on the heat is arranged in the pre-combustion chamber, and ignites the ignition gas flow while forming a flame by the heat thereby. The ignition trigger device also has an ignition spark generating device, and the ignition spark generating device is arranged in the pre-combustion chamber, and ignites the ignition gas flow by forming a flame via an ignition spark thereby. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ignition system for a gas engine, a gas engine comprising such an ignition system, and a method for driving such a gas engine.

  A gas engine is an internal combustion engine in which natural gas, liquefied gas, wood gas, biogas, landfill gas, coal mine gas, hydrogen, or the like can be used instead of liquid fuel. The gas engine is used, for example, in a combined heat and power facility operated in a stationary manner, or as a marine drive device.

  In recent years, it has become possible to use an ignition method for a gas engine that can operate the gas engine with high efficiency, high output, and a small amount of exhaust gas. Such an ignition method is also known as PGI (performance gas injection) and is based on the following points. That is, a fuel gas mixture or ignition gas is injected into a pre-combustion chamber of a gas engine cylinder under high pressure, and the ignition gas ignites while forming a flame in the pre-combustion chamber in contact with a hot surface such as a glow plug. It is. When the ignition gas burns, the ignition gas expands and ignites the fuel gas mixture brought into the main combustion chamber through the connection opening leading to the main combustion chamber of the cylinder.

  Such an ignition system for a gas engine is known from US Pat. In this document, the ignition system comprises an ignition trigger device comprising a heat-based ignition device. The ignition device based on the heat is provided in the pre-combustion chamber of the gas engine, and ignites the ignition gas flow injected into the pre-combustion chamber while forming a flame with heat.

  A further ignition device of the same kind is described in Patent Document 2, for example.

  PGI gas engines, according to the prior art, are based solely on igniting a hot surface such as a pencil-type glow plug. At this time, the pencil-type glow plug is actively heated in a low load region, and reaches a temperature necessary for ignition. Active heating is only stopped when a relatively high engine load range is reached, since energy intake via combustion is maintained at the temperature level required for ignition when the load range is reached. Because it will be sufficient.

  However, it has been found that control of a pencil-type glow plug is very difficult. Pencil-type glow plugs should not be overheated (so as not to significantly impair the stability or life of the pencil-type glow plug), while always maintaining a certain minimum temperature (ignition stability) Because you have to keep it). In particular, adjustment is difficult in partial load operation, and adjustment is further difficult because it is necessary to provide a protective means in contact with the pencil-type glow plug (hot spot). Even a very small manufacturing tolerance in a hot spot can change the heating behavior of the pencil-type glow plug, which can cause standard temperature control to fail.

  Furthermore, the failure of the pencil-type glow plug leads to the failure of the entire gas engine. A further disadvantage of actively heating the pencil glow plug is that a very high temperature is required in particular to start the gas engine, which significantly impairs the stability of the pencil glow plug. . The temperature level required for ignition decreases as the gas engine charge pressure increases.

German Patent Application Publication No. 10217996 German Patent Application Publication No. 102007019882

  SUMMARY OF THE INVENTION An object of the present invention is to provide an ignition system for a gas engine, and to enable the operation reliability of the gas engine or safety against failure to be realized by the ignition system. Another object of the present invention is to provide a gas engine including such an ignition system and a method for driving the gas engine.

  The above problem is solved by an ignition system according to claim 1, a gas engine according to claim 9, and a method according to claim 10. Further embodiments of the invention are described in the respective dependent claims.

  According to a first aspect of the invention, an ignition system for a gas engine, in particular a PGI gas engine, injects an ignition gas stream based on a fuel gas mixture into a precombustion chamber of the cylinder of the gas engine. And an ignition trigger device having an ignition device based on heat, and the ignition device based on the heat is provided in the pre-combustion chamber, thereby forming a flame by heat. While igniting the ignition gas flow. The ignition system according to the present invention is characterized in that the ignition trigger device further includes an ignition spark generating device, and the ignition spark generating device is provided in the pre-combustion chamber, whereby the flame is transmitted via the ignition spark. The ignition gas stream is ignited while forming.

  The invention combines a heat-based ignition device and an ignition spark generator. This provides the following advantages in particular. That is, stable ignition of the ignition gas flow can be ensured by the ignition spark generator at the start of the gas engine and the low load region where the combustion heat for igniting the ignition gas flow based on the heat is small. This improves the operational reliability or safety against failure of the gas engine in a simple and reliable manner, in particular at start-up and in the low load range of the engine to the normal load range.

  By assisting with an ignition spark generator, it is possible to avoid the high heating temperatures required for heat-based igniters in the prior art, thereby providing a heat-based igniter with no load. Stability or lifespan is improved, and at the same time, operation reliability of the gas engine or safety against failure is improved.

  The solution according to the present invention also solves the conflict between avoiding overheating of the igniter based on heat and maintaining the minimum temperature of the igniter based on the heat, as found in the prior art. This facilitates control of the ignition system, in particular feedback control. Furthermore, the system does not fail so easily in terms of manufacturing tolerances, thereby saving costs.

  Furthermore, the ignition spark generator can be used as a backup ignition system or a pre-ignition system when the ignition device based on heat cannot operate due to malfunction due to the redundant action of the ignition spark generator. This also increases the safety against gas engine failure.

  According to an embodiment of the ignition system according to the present invention, the heat-based ignition device has an incandescent body.

  By using an incandescent body, ie as a separate element, the heat-based igniter can be replaced in a simple and inexpensive way after the lifetime of the heat-based igniter has expired or at the time of failure. This reduces the maintenance cost, while further improving the operational reliability or safety of the gas engine. According to an embodiment of the present invention, the ignition system may be mounted together with a pre-combustion chamber in an insert that can be mounted in the cylinder head of the gas engine, for example in a screw-fastened insert.

  According to a further embodiment of the ignition system according to the invention, the incandescent body is configured to heat the incandescent body only by the combustion of a fuel gas mixture.

  According to the above aspect of the invention, the heat-based ignition device is passively heated (only by combustion in the precombustion chamber) and the ignition spark generator is combined. The advantage in this case is that if the heat-based ignition device is heated only passively, it can be constructed very reliably, inexpensively, simply and stably for the high load areas of the engine. An ignition spark generator can be used to start the engine up to its normal load range.

  However, the incandescent body may be combined with active heating. Thereby, the temperature can be actively controlled, thereby improving the adjustment of the glow injection.

  According to an advantageous embodiment of the invention, the heat-based igniter may be combined with a flame trap. The flame trap provides a combustion chamber with at least one opening, at which time the lean stretch limit of the air / gas / exhaust gas mixture and the strong temperature dependence of chemical radical formation ( Necessary for ignition) is fully utilized, thereby achieving very accurate ignition.

  At this time, through the at least one opening, in the internal space of the combustion chamber, during the compression process (in the precombustion chamber), a suitable flow movement causes a large part of the hot exhaust gas obtained from the preceding combustion process to Collected. This achieves a high temperature in the internal space of the combustion chamber during the entire compression process. Due to the components of the hot exhaust gas, high concentrations of chemical radicals can be formed in the internal space of the combustion chamber during the entire compression process without any inherent combustion. In this way, the gas component flowing into the combustion chamber through the at least one opening can be oxidized without an original flame surface. This further increases the temperature and radical concentration in the internal space.

 When the air-fuel mixture flowing into the interior space of the combustion chamber is brought into a suitable ignition window by the ignition gas flow, the flame front can flow out of the combustion chamber. The critical parameters of the flame trap are then the internal gas temperature (at least approximately 1150 K) and the volume and geometry of the at least one opening.

  According to a further embodiment of the ignition system according to the invention, an ignition spark generator is attached, thereby generating an ignition spark based on electrical energy.

  Such an embodiment of the present invention makes it possible to realize an ignition spark generator that is inexpensive and can be controlled very well, particularly in feedback control. This form of the present invention increases the lifespan of generating sparks with less wear by electrical energy, and enhances maintainability with a solution that requires only two spark electrodes.

  According to a further embodiment of the ignition system according to the invention, the ignition system also comprises an ignition voltage control device that is electrically connected to the ignition spark generator. This is for applying an electrical ignition voltage to the ignition spark generator for generating the ignition spark, and the ignition voltage control device controls the amount of the ignition voltage in accordance with the engine load region of the gas engine. It is configured.

  By controlling the amount or height of the ignition voltage, in particular feedback control, the ignition spark generator can be operated at the ignition voltage required for the operating state according to the operating state of the gas engine, so that the wear of the spark electrode is reduced. As a result, the lifetime is increased, and the operation reliability is improved by optimizing the ignition behavior.

  According to the embodiment of the ignition system according to the present invention, the ignition voltage control device is configured as follows. That is, the ignition spark generator is ignited stably in order to start the gas engine and to the ignition gas flow injected by the injector through the combustion of the fuel gas mixture. In order to ignite while forming a flame in the ignition gas stream through the ignition spark until the point at which it is heated to a suitable temperature, an ignition voltage is supplied and a heat-based igniter is mixed with the fuel gas. Ignition spark generator in normal operation of a gas engine, as long as and when heated to a temperature suitable for stable ignition of the ignition gas stream injected by the injector through the combustion of air The supply of the ignition voltage to is stopped.

  According to the embodiment of the present invention, the ignition spark generator is used only when there is not enough combustion heat to perform ignition based on heat on the ignition gas flow. As a result, the ignition spark generator is operated so that it is less worn or damaged, thereby improving the life of the ignition spark generator and the operation reliability or safety against failure, and reducing maintenance costs. Is done.

  In order to determine the temperature of the heat-based igniter, in particular the temperature of the incandescent body, the heat-based igniter may comprise a temperature sensor.

  According to the embodiment of the ignition system according to the present invention, the ignition voltage control device is configured as follows. That is, the ignition spark generator is provided with a smaller amount of electrical ignition energy in the low load region of the engine than in the normal load region of the engine.

  According to the present invention, it has been recognized that sufficiently stable ignition can be ensured even when the ignition spark generator is operated with a small output in the low load region of the engine. By operating the ignition spark generator so as to reduce wear particularly in the low load region of the engine, the life of the ignition spark generator is significantly improved.

  According to a further embodiment of the ignition system according to the invention, the ignition spark generator is formed by an electrical spark plug.

  This provides the following advantages in particular. That is, the spark plug can be procured at a low cost and immediately as a mass-produced product and can be easily replaced.

  According to a second aspect of the invention, a gas engine is implemented with an ignition system according to one or all of the embodiments according to the invention.

  The gas engine according to the invention also has the respective advantages described above, since the gas engine is implemented with the ignition system according to one or all of the embodiments according to the invention. ing.

  According to a third aspect of the invention, there is provided a method for driving a gas engine in which an ignition system according to one or all of the embodiments of the invention is implemented. In this method, the injector is adapted to inject a flow of ignition gas into the pre-combustion chamber of the cylinder and start the gas engine while responding to a predetermined ignition point in the cylinder of the gas engine, and a heat-based ignition device is used in the pre-combustion chamber. The ignition spark generator is used up to the point of being heated to a temperature suitable for stably igniting the ignition gas flow injected by the injector through the combustion of the fuel gas mixture at As a result, ignition is performed while forming a flame in the ignition gas flow via the ignition spark, and the ignition gas flow injected by the injection device through the combustion of the fuel gas mixture in the pre-combustion chamber by the heat-based ignition device During normal operation of the gas engine (i.e., driving without operational failure) when heated to a temperature suitable for stable ignition and as long as it is heated Only ignition device based on heat used, it ignited while forming a flame ignition gas flow through the heat by is performed.

  According to the method according to the invention, a heat-based ignition device and an ignition spark generator are combined. This provides the following advantages in particular. That is, even when there is not enough combustion heat for igniting the ignition gas flow based on the heat, the ignition spark generator can ensure stable ignition of the ignition gas flow. This improves the operational reliability or safety against failure of the gas engine in a simple and reliable manner.

  Assisted by the ignition spark generator, it is possible to abandon the high heating temperatures (due to active heating) required for heat-based igniters in the prior art, thereby heat-based igniters As a result, the stability or life of the gas engine is increased, and the operational reliability or safety of the gas engine is further improved.

  The conflict between avoiding overheating of the heat-based igniter and maintaining the minimum temperature of the heat-based igniter as found in the prior art by the method according to the invention is also solved. This facilitates control of the ignition system, in particular feedback control.

  Furthermore, the ignition spark generator is a backup ignition system or pre-ignition system when the ignition system based on heat fails due to malfunction of the ignition spark generator due to the redundant action of the ignition spark generator and normal operation of the gas engine is not possible. Can be used. This also increases the safety against gas engine failure.

  According to the embodiment of the method according to the present invention, the ignition spark generator is configured to start the gas engine and from the low load region of the engine to the normal load region including the normal load region via the ignition spark. Used to ignite while forming a flame in the ignition gas stream.

  In this way, when the gas engine starts up and during these periods when there is only a small amount of combustion heat for ignition based on the ignition gas flow from the low load region to the normal load region of the gas engine. Only the ignition spark generator can guarantee a stable ignition against the ignition gas flow.

  According to a further embodiment of the method according to the invention, only a heat-based ignition device is used in the high load region of the gas engine, and the ignition gas stream is ignited while forming a flame with heat. In other words, the ignition spark generator can be stopped in a region where the combustion load for performing ignition based on heat is sufficient for the ignition gas flow and the engine load is relatively high, and only the ignition device based on heat is used. Therefore, it is possible to perform operation with low wear and low cost (saving electricity).

  According to a further embodiment of the method according to the invention, an electrical ignition voltage is applied to the ignition spark generator to generate an ignition spark, the amount of electrical ignition energy being the load of the gas engine. It is controlled according to the area.

  By controlling the amount or height of the ignition voltage, particularly feedback control, the ignition spark generator can be operated with the ignition voltage required for the operating state, that is, the electric ignition energy, depending on the operating state of the gas engine. The wear of the ignition electrode is reduced, thereby increasing the lifetime and optimizing the ignition behavior to improve operational reliability.

  According to a further embodiment of the method according to the invention, a smaller amount of ignition voltage or electrical ignition energy is applied to the ignition spark generator in the low load region of the engine than in the normal load region of the engine. Is done.

  As described above, it has been recognized that stable ignition can be ensured in the low load region of the engine even if the ignition voltage or electrical ignition energy supplied to the ignition spark generator is small. By operating the ignition spark generator so as to reduce wear particularly in the low load region of the engine, the life of the ignition spark generator is significantly improved.

  The present invention will be described below based on preferred embodiments with reference to the accompanying drawings.

1 is a schematic partial view of a gas engine according to an embodiment of the present invention.

  FIG. 1 is a schematic partial view of a gas engine 1 operating in the PGI system. The gas engine 1 has a plurality of combustion cylinders 10, and only one of the plurality of combustion cylinders is shown in FIG.

  Each combustion cylinder 10 (hereinafter simply referred to as a cylinder) has a pre-combustion chamber 20 having overflow openings 21 and 22 reaching the main combustion chamber 11 of the cylinder 10.

  The pre-combustion chamber 20 of each cylinder 10 is provided with an ignition system 30, which ignites the main combustion chamber of the cylinder 10 in order to initiate the action of the piston (not shown) of the cylinder 10, i.e. the expansion stroke. It is possible to ignite the fuel gas mixture injected into the fuel cell 11.

  Each ignition system 30 includes an injection device 40 for injecting an ignition gas flow 41 based on a fuel gas mixture under high pressure into the precombustion chamber 20 of the cylinder 10, and an ignition trigger device 50. . The ignition trigger device 50 has a heat-based ignition device 60. The ignition device based on the heat is provided in the precombustion chamber 20 in order to ignite the ignition gas flow 41 while forming a flame with heat. The ignition trigger device further includes an ignition spark generator 70 for igniting the ignition gas flow 41 while forming a flame via the ignition spark.

  The heat-based ignition device 60 includes a flame trap (frame trap) or combustion chamber 61 formed as a hollow body as described above, and an incandescent body 62 formed as a pencil-type glow plug.

  The flame trap 61 is manufactured from a heat-resistant material such as steel or ceramic, and can be reached through at least one opening 61b having a certain size (particularly a certain diameter). A space 61a is provided.

  The incandescent body 62 is configured so that the incandescent body is heated passively or locally in the precombustion chamber 20 or the internal space 61a of the flame trap 61 through the combustion of the fuel gas mixture. According to another embodiment of the present invention, the incandescent body 62 may be formed as an actively heatable element (ie, with its own heating section).

  The ignition spark generator 70 is configured to generate an ignition spark based on electrical energy. In order to realize the generation of such ignition fireworks, an ignition voltage control device 80 is provided, and the ignition voltage control device is electrically connected to the ignition spark generation device 70 via the electric wire 81, and the ignition An electrical ignition voltage is applied to the ignition spark generator 70 in order to generate a spark.

  The ignition voltage control device 80 is configured to control, particularly feedback control, the magnitude of the ignition voltage or electrical ignition energy in accordance with the engine load region of the gas engine 1. Thereby, in the low load region of the engine, a smaller amount of ignition voltage is applied to the ignition spark generator 70 than in the normal load region of the engine.

  According to this embodiment, the low load region of the engine is defined as about 1% to about 40% of the effective output of the engine, and the normal load region of the engine is defined as about 41% to about 70% of the effective output of the engine. The high load region of the engine is defined as about 71% to about 100% of the effective output of the engine. It goes without saying that other area divisions relating to the engine load are also included in the scope of the present invention.

  According to the present embodiment, the spark generating device 70 is formed by an electric spark plug, and the spark plug is screwed into the pre-combustion chamber 20, thereby two spark electrodes of the spark plug. 71 and 72 protrude into the pre-combustion chamber 20.

  Embodiments of the method according to the invention for driving a gas engine 1 comprising an ignition system 30 are described below.

  In any case, in order to start the operation process of the piston of the cylinder 10 of the gas engine 1, that is, the expansion stroke, the injection device 40 causes the ignition gas flow 41 to flow to the cylinder 10 in response to a predetermined ignition timing of the cylinder 10. The pre-combustion chamber 20 is injected.

  When the gas engine 1 is started and through the combustion of the fuel gas mixture in the internal space 61a of the precombustion chamber 20 or the flame trap 61, the incandescent body 62 of the ignition device 60 based on heat is injected by the injection device 40. In order to ignite while forming a flame in the ignition gas stream 41 through the ignition spark until the time when the ignition gas stream 41 is heated to a temperature suitable for stable ignition, an ignition spark is generated. A device 70 is used.

  That is, the ignition voltage control device 80 is configured as follows. That is, the ignition voltage control device 80 causes the ignition spark generator 70 to start the gas engine 1 and through the combustion of the fuel gas mixture, so that the ignition device 60 based on heat (or the incandescence of the ignition device) is generated. Until the point at which the body 62) is heated to about 1150K or 877 ° C., the minimum temperature suitable for stably igniting the ignition gas stream 41 injected by the injector 40, via the ignition spark Ignition voltage is supplied to ignite the ignition gas stream (41) to form a flame, and the ignition gas stream injected by the injector 40 through the combustion of the fuel gas mixture by the ignition device 60 based on heat Points to the ignition spark generator 70 in normal operation of the gas engine 1 as long as and when heated to a minimum temperature suitable for stably igniting 41 Or the supply voltage is adjusted, or the operation of the ignition spark generating device 70 is stopped.

  In order to determine the temperature of the ignition device 60 based on heat, in particular, the temperature of the incandescent body 62, the ignition device 60 based on the heat includes a temperature sensor not shown in the figure. Electrically connected.

  According to this embodiment of the present invention, the ignition spark generator 70 causes the ignition gas flow 41 to flow through the ignition spark from the start of the gas engine 1 and from the low load region to the normal load region of the gas engine 1. Used to ignite while forming a flame.

  In order to cause the ignition spark generator 70 to generate an ignition spark by the ignition voltage control device 80, an electrical ignition voltage is applied, and the amount or magnitude of the ignition voltage or electrical ignition energy depends on each individual gas engine 1. The ignition spark generator 70 is operated at an ignition voltage lower than the ignition voltage in the normal load region of the engine in the low load region of the engine.

  When the gas engine 1 is driven by the ignition spark generator 70, the ignition gas flow 41 injected into the precombustion chamber 20 by the injection device 40 forms a flame by the electrical ignition spark at the spark electrodes 71 and 72. Ignited. The gaseous mixture in the pre-combustion chamber 20 is conveyed from the pre-combustion chamber 20 through the overflow openings 21 and 22 into the main combustion chamber 11 that is in communication with the pre-combustion chamber 20, thereby air / fuel mixing. The gas (air / fuel gas mixture) is ignited. The air / fuel mixture is in the main combustion chamber 11 of the cylinder 10, and when the air / fuel mixture burns, an expansion stroke or operation process of a piston provided in the cylinder 10 is started.

  Further, when the gas engine 1 is driven by the ignition spark generator 70, the incandescent body 62 of the heat-based ignition device 60 is slowly heated to a predetermined minimum temperature of about 1150K or 877 ° C.

  Furthermore, during the compression process of the gas engine 1, a hot gaseous mixture that is not completely combustible resulting from the preceding individual combustion strokes is introduced into the precombustion chamber 20 of the cylinder 10, and opens through the opening 61 b of the flame trap 61. And collected in the internal space 61a of the flame trap.

  Due to the hot gaseous mixture formed by the exhaust gas, high concentrations of chemical radicals (and carbon dioxide) can be formed in the internal space 61a of the flame trap 61 without any inherent combustion. In this way, the gas component flowing into the internal space 61a of the flame trap 61 can be oxidized even without the original flame surface. This further increases the temperature and radical concentration in the internal space 61a.

  The incandescent body 62 of the heat-based ignition device 60 stably ignites the ignition gas stream 41 injected by the injection device 40 through the combustion of the fuel gas mixture in the precombustion chamber 20 or the internal space 61a of the flame trap 61. The ignition spark generator 70 is stopped in the normal operation of the gas engine 1 when it is heated to the minimum temperature suitable for performing the ignition, and then only the ignition device 60 based on heat is used, and a flame is formed by the heat. The ignition gas stream 41 is ignited while being ignited.

  In other words, according to this embodiment of the present invention, only the ignition device 60 based on heat is used in the high load region of the gas engine 1, and the ignition gas stream 41 is ignited while forming a flame with heat.

  When the gas engine 1 is driven only by the heat-based ignition device 60, during the compression process of the gas engine 1, the hot and non-combustible gaseous mixture resulting from the combustion stroke of the preceding gas engine is in the cylinder 10. It is guided into the pre-combustion chamber 20 and collected in the internal space 61a of the flame trap through the opening 61b of the flame trap 61.

  Thereafter, the gaseous mixture that cannot be completely combusted collected in the internal space 61 a is kept at a minimum temperature of 1150 K, that is, 877 ° C. using the incandescent body 62.

  Due to the hot gaseous mixture formed by the exhaust gas, high concentrations of chemical radicals (and carbon dioxide) are formed in the internal space 61a of the flame trap 61 throughout the compression process, even without the original combustion. As a result, the gas component flowing into the internal space 61a of the flame trap 61 is oxidized even without the original flame surface. As a result, the temperature and radical concentration in the internal space 61a are further increased.

  Gaseous mixtures that cannot be completely combusted are limited in terms of the flame extension of the lean mixture outside the internal space 61a or in the opening 61b in terms of exhaust gas concentration (carbon dioxide), mixing ratio (Lambda), turbulence and inflow velocity (lean The flame extinguishes due to the stretch limit), and the chemical reaction does not flow out from the internal space 61a of the flame trap 61 in the form of a flame surface. For this reason, the reaction (“flame”) is kept in the internal space 61 a of the flame trap 61 for the time being, so that an externally “fixed flame surface” is formed in the internal space 61 a of the flame trap 61.

  At a time corresponding to a predetermined ignition time of the cylinder 10 of the gas engine 1, the injection device 40 injects an ignition gas flow 41 into the precombustion chamber 20 under high pressure, thereby via the opening 61 b of the flame trap 61. The fuel gas mixture of the incoming ignition gas stream 41 increases the gaseous mixture in the internal space 61a of the flame trap 61 that cannot be completely combusted until that time, or increases the fuel component of the gaseous mixture that cannot be completely combusted, The gaseous mixture formed thereby ignites in contact with the incandescent body 62 that has become sufficiently hot, and burns while forming a flame.

  When the gaseous mixture burns while forming a flame in this way, the flame surface flows out from the internal space 61 a of the flame trap 61 through the opening 61 b of the flame trap 61. The flame surface flowing out from the internal space 61 a of the flame trap 61 ignites while forming a flame in the gaseous mixture in the precombustion chamber 20. Combustion of the gaseous mixture in the pre-combustion chamber 20 is caused by expansion from the pre-combustion chamber 20 through the overflow openings 21 and 22, and the main combustion chamber of the cylinder 10 of the gas engine 1 communicated with the pre-combustion chamber 20. 11, whereby the air / fuel mixture is ignited in the main combustion chamber 11 of the cylinder 10. The air / fuel mixture starts an expansion stroke or an operation process of a piston provided in the cylinder 10 when the air / fuel mixture burns.

  Finally, in the gas engine 1 based on the PGI system according to the present invention, the ignition gas flow 41 injected into the precombustion chamber 20 and the air / fuel mixture (air / fuel mixture) injected into the main combustion chamber 11 of the cylinder 10. It should be noted that “gas mixture” is based on the same gaseous fuel or combustion gas.

DESCRIPTION OF SYMBOLS 1 Gas engine 10 (combustion) cylinder 11 Main combustion chamber 20 Precombustion chamber 21 Overflow opening 22 Overflow opening 30 Ignition system 40 Injection device 41 Ignition gas flow 50 Ignition trigger device 60 Ignition device based on heat 61 Flame trap 61a Internal space 61b Opening 62 Incandescent body 70 Ignition spark generator 71 Spark electrode 72 Spark electrode 80 Ignition voltage controller 81 Electric wire

Claims (15)

An ignition system (30) for a gas engine (1), wherein an ignition gas flow (41) based on a fuel gas mixture is fed into a precombustion chamber (20) of a cylinder (10) of the gas engine (1). And an ignition trigger device (50) having a heat-based ignition device (60), the heat-based ignition device being the pre-combustion chamber (20) in an ignition system, wherein the ignition gas stream (41) is ignited while forming a flame by heat,
The ignition trigger device (50) further includes an ignition spark generator (70), and the ignition spark generator is provided in the pre-combustion chamber (20), whereby a flame is generated via the ignition spark. An ignition system (30) characterized in that the ignition gas stream (41) is ignited while forming.   The ignition system (30) of claim 1, wherein the heat-based ignition device (60) comprises an incandescent body (62).   The ignition system (30) of claim 2, wherein the incandescent body (62) is configured to heat the incandescent body only through combustion of a fuel gas mixture.   The ignition system (30) of claim 2, wherein the incandescent body (62) can be combined with active heating, whereby the temperature can be actively controlled.   The ignition system (30) according to any one of claims 1 to 3, wherein the ignition spark generator (70) is configured to generate an ignition spark based on electrical energy.   An ignition voltage control device (80) electrically connected to the ignition spark generator (70) for applying an electrical ignition voltage to the ignition spark generator (70) for generating an ignition spark The ignition voltage control device (80) is configured to control the amount of ignition voltage or electrical ignition energy according to the engine load region of the gas engine (1). Ignition system (30) according to claim 5, characterized in that.   The ignition voltage control device (80) causes the ignition spark generator (70) to start the gas engine (1), and the heat-based ignition device (60) burns a fuel gas mixture. The ignition gas flow through the ignition spark until a point where the ignition gas flow (41) injected by the injection device (40) is heated to a temperature suitable for stable ignition. In order to ignite while forming a flame in the flow (41), an ignition voltage is supplied and the heat-based igniter (60) is injected by the injector (40) via combustion of a fuel gas mixture The ignition spark generator (70) in normal operation of the gas engine (1) when heated to a temperature suitable for stable ignition of the ignition gas stream (41) Point to Ignition system according to claim 6, characterized in that it is configured to stop supplying the voltage (30).   The ignition voltage control device (80) applies a lower ignition voltage or electrical energy in the low load region of the engine than in the normal load region of the engine to the ignition spark generator (70). The ignition system (30) according to claim 6 or 7, characterized in that the ignition system (30) is configured as follows.   The ignition system (30) according to any one of claims 5 to 7, characterized in that the ignition spark generator (70) is formed by an electrical spark plug.   A gas engine (1) comprising an ignition system (30) according to any one of the preceding claims. A method for driving a gas engine (1) comprising an ignition system (30) according to any one of the preceding claims,
The injector (40) responds to a predetermined ignition time of the cylinder (10) of the gas engine (1) while igniting gas flow (41) in the pre-combustion chamber (20) of the cylinder (10). Spray
When the gas engine (1) is started, and the heat-based ignition device (60) stabilizes the ignition gas flow (41) injected by the injection device (40) via combustion of a fuel gas mixture The ignition spark generator (70) is used until a point at which it is heated to a temperature suitable for igniting, thereby forming a flame in the ignition gas stream (41) via the ignition spark. Ignition was performed while
The heat-based ignition device (60) is heated to a temperature suitable for stably igniting the ignition gas stream (41) injected by the injection device (40) through combustion of a fuel gas mixture. When and when heated, only the heat-based ignition device (60) is used in normal operation of the gas engine, thereby forming a flame in the ignition gas stream (41) via heat. A method characterized in that ignition takes place.   The ignition spark generator (70) is configured to start the gas engine (1) and from the low load region of the gas engine (1) to the normal load region including a normal load region via the ignition spark. 12. Method according to claim 11, characterized in that it is used for ignition while forming a flame in the ignition gas stream (41).   In the high load region of the gas engine (1), only the ignition device (60) based on the heat is used, thereby igniting the ignition gas flow (41) while forming a flame by heat. The method according to claim 11 or 12.   An electrical ignition voltage or ignition energy is applied to the ignition spark generator (70) to generate an ignition spark, and the amount of the ignition voltage is controlled according to the load region of the gas engine (1). 14. A method according to any one of claims 11 to 13, characterized in that:   15. The method according to claim 14, characterized in that a lower ignition voltage or ignition energy is applied to the ignition spark generator (70) in a low load region of the engine than in a normal load region of the engine.