JPH0683945U - Load cutoff control device for lean burn gas engine - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention relates to a lean combustion gas engine of a sub-chamber type having a main chamber 1 and a sub chamber 2, wherein "the gas pressure in the main chamber side and the gas pressure in the sub chamber side at the time of load shedding are unbalanced". The purpose is to eliminate the "state." [Configuration] When the load is cut off, the gas solenoid valve for the main chamber and the gas solenoid valve for the sub chamber are closed to eliminate the unbalanced state between the gas pressure on the main chamber side and the gas pressure on the sub chamber side, and the generator load is cut off. The vessel was configured to open 1 second after the opening command. When the load is cut off, a gas pipe is connected to the inlet side of the Venturi mixer in order to eliminate the fuel gas in the sub chamber from the gas pipe.
An unbalanced state is eliminated by providing a gas solenoid valve for load cutoff control on the way and opening the gas solenoid valve for load cutoff control.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a load cutoff control mechanism for a lean burn gas engine of a sub-chamber type.

[0002]

[Prior art]

 Conventionally, the technology related to the auxiliary chamber lean-burn gas engine has been known. For example, it is like the technique described in JP-A-63-277866. However, in the conventional technique, as shown in the drawing of the defect of the conventional technique in FIG. 4, the following defects have occurred. That is, in the case of a lean burn gas engine that drives a generator, if the circuit breaker is opened from 100% load during a major failure or during the total inspection before use, a sudden load change to 0% load will occur. ,. The gas pressure in the main chamber (mixing gas pressure) drops sharply due to the operation of the governor. However, the pressure of the gas pressure on the sub-chamber side slows down, and an unbalanced state occurs between the gas pressure on the main chamber side and the gas pressure on the sub chamber side. ． Due to the unbalanced state, the combustion state becomes a misfire state, afterburning (post-combustion) occurs in the exhaust manifold, and the reflected pressure of the afterburning is received, and as shown in Fig. 5, the flashback into the air supply manifold occurs. Induce a phenomenon. In some cases, there is a risk of equipment damage or personal injury. ． In order to prevent the above problems from occurring, it is necessary to reduce the rated output by 100%.

[0003]

[Problems to be solved by the device]

 An object of the present invention is to solve the above-mentioned problem of the prior art, "an unbalanced state of the gas pressure on the main chamber side and the gas pressure on the sub chamber side when the load is cut off".

[0004]

[Means for Solving the Problems]

 The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described. That is, when the load is cut off, the gas solenoid valve for the main chamber and the gas solenoid valve for the sub chamber are closed to eliminate the unbalanced state between the gas pressure on the main chamber side and the gas pressure on the sub chamber side, and the generator load circuit breaker is closed. Is configured to perform the opening operation one second after the opening command.

In order to eliminate the fuel gas in the sub-chamber from the inside of the gas pipe when the load is cut off, a gas pipe is connected to the inlet side of the venturi mixer, and a load cut-off control solenoid valve S V3 is provided in the middle of the gas pipe. By opening the control solenoid valve SV3, the unbalanced state is eliminated.

[0006]

[Action]

 Next, the operation will be described. That is, in the case of the technology of claim 1, the main chamber gas solenoid valves SV1 and SV2 and the sub chamber gas solenoid valves SV4 and SV5 are opened and closed by the load break command of the generator circuit breaker, and the load circuit breaker is activated. By delaying the operation, it is possible to eliminate the "unbalanced state of the gas pressure on the main chamber side and the gas pressure on the sub chamber side when the load is cut off" that occurs when the load suddenly decreases. Also in the case of the technique of claim 2, the pressure gas in the sub-chamber 2 is released to the inlet side of the venturi mixer 18 by opening the load cutoff control gas solenoid valve SV3, so that the sub-chamber is utilized by using the negative pressure. The pressure can be reduced, and the “unbalanced state between the gas pressure on the main chamber side and the gas pressure on the sub chamber side when the load is cut off” that occurs when the load suddenly decreases can be eliminated.

[0007]

【Example】

 Next, examples will be described. Fig. 1 is a drawing showing a flow chart of a supply / fuel gas system piping of a lean-burn type combustion engine of a sub-chamber, Fig. 2 is a drawing showing a time schedule at the time of load shedding of the present invention, and Fig. 3 is a load shedding control of the present invention. Fig. 4 is a drawing showing a block diagram at the time, Fig. 4 is a drawing showing a pressure unbalanced state at the time of conventional load shedding, Fig. 5 is a drawing showing flashback and afterburning at the time of conventional load shedding, and Fig. 6 is the main feature of the present invention. It is drawing which shows the time schedule of fuel gas solenoid valves SV1 and SV2.

The sub-chamber lean burn gas engine is provided with a sub-chamber ignition plug and a main-chamber ignition plug, which are constantly ignited when the engine is operating, in the sub-chamber and the main chamber, respectively. The ignition timing of the lag is set to be later than the ignition timing of the ignition plug for the sub chamber, or at the same time, the propagation flame ignited by the ignition plug for the sub chamber reaches the ignition plug for the main chamber, The chamber ignition plug is configured to ignite.

This will be described with reference to FIG. During normal operation, on the main chamber side, from the fuel gas tank, through the main fuel gas solenoid valves SV1 and SV2, main chamber gas guulators 20 and 21, step motor 19, venturi mixer 18, supercharger 17, air Mixing gas is supplied from the air supply manifold 14 to the main chamber 1 of the cylinder head through the cooler 16 and the throttle valve 15.

On the other hand, on the sub-chamber side, from the sub-fuel gas solenoid valve SV6, the gas booster 13 to the sub-chamber gas solenoid valves SV4 and SV5, and the sub-chamber gas regulator 12, from the sub-chamber air supply manifold 11 to the sub-chamber. 2 is supplied to the sub chamber as a sub chamber gas. Reference numeral 23 is an air filter, 24 is an explosion-proof safety valve, 25 is an instrument panel, and 26 is a starting solenoid valve. The gas booster 13 includes a strainer 28, an aftercooler 32, a gas regulator 31, a receiver tank 30, a check valve 29 and the like.

For example, when the breaker of the generator is opened to cut off the load on the engine, the gas electromagnetic valves SV1 and SV2 for the main chamber and the gas electromagnetic valve SV4 The SV5 is closed. During this time, since the circuit breaker is in the closed state, the engine is under load, the fuel gas inside the engine is consumed, and the engine is in the fuel supply state under 100% load.

On the other hand, the timer T is activated at the same time as the generator circuit breaker opening command, and after about 1 second, the circuit breaker is opened, and the main chamber gas solenoid valves SV1 and SV2 and the sub chamber gas solenoid valves SV4 and SV5 are opened. The engine is opened, and the engine enters the no-load operation state. Due to such a series of opening and closing operations of the main chamber gas solenoid valves SV1 and SV2 and the sub chamber gas solenoid valves SV4 and SV5, "the main chamber side gas pressure and the sub chamber side gas pressure are unbalanced when the load is cut off. Can be eliminated. The time schedule for this control is shown in FIG. Further, a flow chart of this control is shown in FIG.

Next, the invention of claim 2 will be described. In this case, when the load is opened when the generator circuit breaker is opened, the open electrical contact signal is used to open the load cutoff control gas solenoid valve SV3 for a certain period of time. As a result, a part of the fuel gas supplied to the sub-chamber 2 is discharged to a part of the venturi mixer 18 on the upstream side which is always in the negative pressure state, so that the gas pressure in the sub-chamber 2 is rapidly lowered, and thereby the mixing is performed. The rate of pressure change in the transient state between the gas pressure and the gas pressure in the sub-chamber is made approximately the same. By opening and closing the series of gas solenoid valves SV1 and SV2 for main chambers, gas solenoid valves SV4 and SV5 for sub chambers, and gas solenoid valve SV3 for load cut-off control in this way It is possible to eliminate the “unbalanced state of the gas pressure on the chamber side”. This time schedule is illustrated in FIG.

[0014]

[Effect of device]

 Since the present invention is configured as described above, the following effects are produced. That is, first, it is possible to eliminate the "unbalanced state between the gas pressure on the main chamber side and the gas pressure on the sub chamber side at the time of load shedding" that occurs when the load suddenly decreases in the sub-chamber lean burn gas engine. This made it possible to maintain a stable operating condition.

Secondly, it is not necessary to consider the load cutoff characteristic as one of the constraint conditions when setting the rated output.

[Brief description of drawings]

FIG. 1 is a drawing showing a flow chart of a supply gas / fuel gas system piping of a sub-chamber lean combustion gas engine.

FIG. 2 is a diagram showing a time schedule for load shedding according to the present invention.

FIG. 3 is a diagram showing a block diagram of the present invention during load shedding control.

FIG. 4 is a drawing showing a conventional pressure unbalanced state when a load is cut off.

FIG. 5 is a drawing showing conventional flashback and afterburning at the time of load shedding.

FIG. 6 is a view showing a time schedule of main fuel gas solenoid valves SV1 and SV2 of the present invention.

[Explanation of symbols]

 1 Main chamber 2 Sub chamber SV1 / SV2 Main chamber gas solenoid valve SV3 Load cutoff control gas solenoid valve SV4 / SV5 Sub chamber gas solenoid valve 11 Sub chamber air supply manifold 13 Gas booster 14 Air supply manifold 15 Throttle valve 16 Air Cooler 17 Supercharger

Claims (2)

[Scope of utility model registration request] 1. When the load is cut off, the gas solenoid valve for the main chamber and the gas solenoid valve for the sub chamber are closed to eliminate an unbalanced state between the gas pressure on the main chamber side and the gas pressure on the sub chamber side, and the generator is closed. A load cut-off control device for a lean burn gas engine, wherein the load breaker is configured to be opened 1 second after an opening command. 2. When the load is cut off, a gas pipe is connected to the inlet side of the Venturi mixer in order to eliminate the fuel gas in the sub-chamber from the inside of the gas pipe. A load cut-off control device for a lean burn gas engine, characterized in that an unbalanced state is resolved by opening a gas solenoid valve for use.