JP2012132420A - Apparatus and method for detecting failure of fuel supply valve in gas engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and method for detecting a failure of a fuel supply valve supplying through injection gaseous fuel during air supply in a gas engine, and especially, a failure detection apparatus and method of the fuel supply valve in the gas engine, which can detect gas leakage during a valve closing period, generated during operation in the fuel supply valve.SOLUTION: The failure detection apparatus includes: a vibration sensor 51 arranged in the fuel supply valve 26; a cycle phase supply device supplying a signal indicating opening and closing timing of the fuel supply valve; and a failure transmitter 50 determining the fuel supply valve to be abnormal, based on a vibration due to opening and closing of the fuel supply valve 26, with a vibration measurement signal supplied by the vibration sensor 51 and a fuel supply valve opening and closing timing indication signal inputted thereto, and outputting a failure signal. The apparatus detects the failure of the fuel supply valve, based on a vibration strength when the valve is opened and closed, and issues a warning.

Description

  The present invention relates to an apparatus and a method for detecting an abnormality of a fuel supply valve that injects and supplies gaseous fuel during supply in a gas engine, and in particular, to detect a gas leak when the fuel supply valve is closed during operation. The present invention relates to an abnormality detection apparatus and method capable of performing the above.

Gas engines that use gaseous fuels such as compressed natural gas, liquefied propane gas, and compressed hydrogen attract great attention as high-efficiency, clean engines that can be used not only for power supply but also for cogeneration facilities that use exhaust heat. Collecting.
In general, a gas engine having multiple cylinders is provided for each engine cylinder as a gaseous fuel supply system, a fuel gas supply header in which gaseous fuel is supplied from a gas fuel storage device through a pressure regulating valve and a filter, And a fuel supply valve for supplying gaseous fuel from the fuel gas supply header via the branch pipe. The fuel supply valve injects gaseous fuel into the air supply port to generate air supply in which a predetermined amount of fuel gas is evenly mixed, and enters the engine cylinder via an air supply valve that opens every engine cycle. It is configured to supply.

In a gas engine, it is necessary to supply gaseous fuel for each engine cycle, and it is necessary to accurately adjust the gas concentration in order to efficiently burn in the engine cylinder. Furthermore, in the gas engine, the volume of fuel supplied to the engine cylinder is larger than that of liquid fuel such as gasoline.
For this reason, the fuel supply valve has a large capacity in the form of forming a large opening with a short stroke so that fuel gas can be accurately measured and supplied by regulating the valve opening period by electromagnetic force drive, for example. High-speed solenoid valves are used.

  As such a fuel supply valve, the valve body and the valve seat come into contact with a large area plane with a plurality of concentric grooves, and even when the valve is opened, even a slight stroke of about 0.3 mm or less is used. A large amount of gas can be passed because the body groove and the valve seat groove communicate with each other, and a high-speed opening and closing of about 2 to 3 ms is possible between the fully closed and fully opened state by a powerful solenoid and a powerful spring. It is possible to use a solenoid-driven face-type poppet valve or the like.

  A fine filter is installed on the fuel gas supply side of the fuel supply valve, and since there is little backflow from the air supply pipe to the fuel supply valve, foreign matter usually reaches the valve seat of the fuel supply valve. Never do. However, it cannot be said that a situation where foreign matter enters the fuel supply valve and bites into the fuel supply valve does not occur due to an abnormality in the filter or an abnormality in the engine cylinder. The fuel supply valve closes with the large-area faces of the valve body and valve seat coming into contact with each other, so if a foreign object is caught between the faces, a large amount of gas will leak even if a slight gap is created. Become.

If a gas leakage abnormality occurs in the fuel supply valve, not only the gas concentration of the air-fuel mixture in the engine cylinder will be higher than the combustible range and combustion will not stop, but also the unburned air-fuel mixture will flow down to the exhaust manifold When the exhaust gas from the engine cylinder is collected and mixed, the fuel gas is diluted by oxygen in the exhaust gas, and the air-fuel ratio in the exhaust manifold may show an air-fuel ratio that belongs to the combustible range.
If the air-fuel mixture in the exhaust manifold is in the flammable range, the energy released by ignition and combustion in the exhaust manifold is supercharged in the downstream of the exhaust manifold, exhaust gas purification catalyst, boiler, silencer, etc. May be damaged.

  For this reason, when a gas leak occurs when the fuel supply valve is closed, it is desired to detect it immediately and take some measures such as stopping the engine. For this purpose, an abnormality detection device that immediately detects the gas leakage of the fuel supply valve during operation of the gas engine is required.

In a gas engine, fuel gas is measured by a fuel supply valve during an air supply stroke and supplied to an air supply port. The fuel gas is metered by dividing the opening period of the fuel supply valve into a predetermined time. That is, the fuel supply valve opens at a predetermined crank angle position and closes at a predetermined crank angle position advanced by a predetermined angle, thereby supplying a predetermined amount of gaseous fuel during supply.
When the electromagnet is used to open the fuel supply valve, the magnetic body provided on the valve body collides with the magnet, causing vibration and noise, and when the electromagnet is de-energized and the valve body is pressed against the valve seat with a spring The valve body and the valve seat come into contact with each other to generate vibration and noise.

In addition, when an abnormality such as a foreign matter is caught in the fuel supply valve and a collision different from the normal time occurs, a vibration different from the normal time is generated at a specified crank angle position. When the cause is foreign matter bite, especially when the valve is closed, the travel distance of the valve body is reduced, or soft foreign matter is interposed between the valve body and the valve seat to reduce the collision energy. Vibration is reduced.
In this way, when the fuel supply valve bites foreign matter and cannot be closed properly, a change occurs in the vibration generated with the opening / closing movement of the valve body.
However, since the stroke of the valve body is extremely short at the submillimeter level, the generated vibration and noise are not remarkable as compared with those generated in the supply / exhaust valve.

JP 2006-250141 A JP 2002-240479A

Patent Document 1 discloses a device for detecting an open failure in which a hydrogen injection valve that supplies hydrogen as a fuel to a gas engine such as a rotary engine remains open when closed and causes gas leakage. The disclosed open failure detection device is provided with a shutoff valve upstream of the hydrogen injection valve, closes the hydrogen injection valve and the shutoff valve when inspecting, and observes the pressure in the fuel supply passage sandwiched between these valves If the pressure decreases, the hydrogen injector is judged to have a leak.
Since the apparatus described in Patent Document 1 needs to be inspected with the hydrogen shutoff valve closed, it can be inspected only when the engine is stopped. Therefore, it cannot be used to detect and take measures immediately after the occurrence of an accident in which a foreign object becomes caught during operation and cannot be completely closed.

  Patent Document 2 discloses a foreign matter biting detection means for reliably detecting when foreign matter is caught in an intake / exhaust valve of an internal combustion engine so that the engine does not fall into a starting failure or the like. Has been. Here, as the foreign object biting detection means, in addition to the rotational speed in the compression stroke, the current value flowing through the starter, the temperature in the supply / exhaust pipe, the vibration of the engine is cited, and a vibration sensor is attached to the cylinder block and knocking is performed. It detects and uses vibrations and vibrations that occur as the intake / exhaust valve is seated.

The device described in Patent Document 2 detects the biting of foreign matter in the air supply / exhaust valve, and in order to distinguish and detect the valve closing vibration generated with the seating of the air supply / exhaust valve from the vibrations of various engines. A filter is used to select vibrations, and it is determined that biting has occurred when the valve closing timing is predicted and the actual valve closing vibration timing continues to deviate four times or more from the expected time.
The seating vibration of the fuel supply valve installed in the cylinder head has a small stroke and surface contact, so it is small compared to the seating vibration of the air supply / exhaust valve, and it is difficult to detect with certainty by the vibration sensor attached to the cylinder block. It is.
In addition, if the determination is made that the timing of the valve closing vibration deviates four times or more from the expected value, the abnormal state of the fuel supply valve becomes too long, and ignition combustion in the exhaust manifold cannot be avoided.

  Therefore, the problem to be solved by the present invention is an apparatus and method capable of detecting and notifying an abnormality of a fuel supply valve that injects and supplies gaseous fuel during supply in a gas engine, and particularly occurs during operation of the fuel supply valve. An object of the present invention is to provide an abnormality detection device and method for a fuel supply valve in a gas engine that can quickly detect gas fuel leakage when the valve is closed.

In order to solve the above problems, a fuel supply valve abnormality detection device for supplying gaseous fuel to an air supply port in a gas engine of the present invention displays a vibration sensor installed in the fuel supply valve and the opening and closing timing of the fuel supply valve. Cycle phase signal supply device that supplies signals, vibration measurement signal supplied from vibration sensor and fuel supply valve open / close timing display signal are input, and abnormality of fuel supply valve is determined based on vibration accompanying fuel supply valve open / close And an abnormal transmission device that outputs an abnormal signal.
The abnormality transmitting device may determine that the fuel supply valve is abnormal when vibration associated with opening and closing of the fuel supply valve becomes a value equal to or less than a predetermined threshold. Further, it may be determined that the fuel supply valve is abnormal when the vibration associated with the opening and closing of the fuel supply valve is reduced to a predetermined value or more compared to the previous value.

  In order to solve the above-described problem, the abnormality detection method for a fuel supply valve for supplying gaseous fuel to an air supply port in a gas engine according to the present invention is such that the vibration of the fuel supply valve detected at the opening and closing timing of the fuel supply valve is predetermined. When it falls below the value or when it falls below a predetermined value compared to the previous value, it is notified that the fuel supply valve is abnormal.

The apparatus and method for detecting an abnormality of a fuel supply valve in a gas engine according to the present invention includes a vibration sensor provided in a casing in which a valve seat of the fuel supply valve is arranged, and vibrations associated with opening and closing of the fuel supply valve measured by the vibration sensor. When the normal vibration and intensity are different, it is judged that an abnormality has occurred in the fuel supply valve and an alarm is given.
Therefore, when a leakage accident occurs in the fuel supply valve, an abnormality of the fuel supply valve can be detected immediately after the air supply stroke is completed in the same cycle.
According to the present invention, abnormalities in the fuel supply valve such as foreign object biting that occurred during engine operation are detected and notified immediately with high reliability, so appropriate measures are taken to prevent a fuel leakage accident from developing into a major accident. Can take.

  The abnormality detection device may acquire vibration information from the vibration sensor when the rotation of the crankshaft reaches an appropriate phase position based on the cycle phase. The cycle phase can be determined based on a measurement signal input directly from a rotational phase meter that detects rotation of the crankshaft. Moreover, it can also input via an engine control apparatus. Furthermore, at a specific phase position, a fuel supply valve opening / closing command signal generated by the engine control device can be input and used as information acquisition timing.

  The apparatus and method for detecting an abnormality of a fuel supply valve in a gas engine according to the present invention immediately when a leakage abnormality occurs during a valve closing period due to a foreign matter being caught in the fuel supply valve in the gas engine. Since an abnormality is detected and an abnormality signal is generated, it becomes possible to take effective measures before an accident such as combustion in the exhaust manifold develops.

It is a flow sheet explaining the abnormality detection apparatus of the fuel supply valve in the gas engine which concerns on one Example of this invention. It is sectional drawing which shows notionally the structure of the fuel supply valve in a present Example. It is sectional drawing which shows the attachment position of the vibration sensor in a present Example. It is a graph explaining the abnormality detection principle of a present Example. It is a flowchart explaining the abnormality detection procedure of a present Example.

Hereinafter, embodiments of a fuel supply valve abnormality detection device and method in a gas engine of the present invention will be described with reference to the drawings. In the drawings with different figure numbers, the same reference numerals are assigned to the components having the same functions to facilitate understanding.
FIG. 1 is a flow sheet showing an outline of a gas engine to which a fuel supply valve abnormality detection device according to one embodiment of the present invention is applied.

In the gas engine 10 having a plurality of cylinders according to the present embodiment, a space in which each cylinder is surrounded by the cylinder head 20, the side wall of the engine cylinder 11 and the piston 12 is used as a combustion chamber, as in the case of an internal combustion engine using liquid fuel. The combustion chamber is connected to an air supply port 13 via an air supply valve 15 and to an exhaust port 14 via an exhaust valve 16.
When the air supply valve 15 is opened to supply the air supply mixed with the fuel gas to the combustion chamber, and after being compressed and ignited by the spark plug 19, the gas in the combustion chamber expands and the piston 12 is pushed down in the engine cylinder 11. Then, the crankshaft 21 is rotated through the connecting rod.

The crankshaft 21 is continuously rotated by being driven with an appropriate phase difference by the pistons of the multiple cylinders constituting the gas engine. As the crankshaft 21 rotates, the exhaust valve 16 opens while the piston 12 is pushed up through the bottom dead center, and the combustion gas is removed through the exhaust port 14.
When the crankshaft 21 rotates, the generator 22 can be driven to generate electric power.
The combustion chamber is composed of a main combustion chamber 17 in which the piston 12 reciprocates, and a sub chamber 18 having an opening in the ceiling of the main combustion chamber 17 and provided with a spark plug 19 to improve performance.

  The supply air is supplied to the supply air manifold 23 through the supercharger 35. The air supply manifold 23 is connected to the air supply ports 13 of a plurality of cylinders by branch pipes, and distributes homogeneous air supply to each cylinder. The supercharger 35 uses the energy of the exhaust gas to increase the density of the supply air, and the engine output can be increased by increasing the density of the supply air.

In each cylinder of the gas engine 10, for each cylinder, gaseous fuel is injected and injected into the air supply at the air supply port 13 to generate an air-fuel mixture having an appropriate gas concentration and supply it to the combustion chamber.
On the other hand, the exhaust gas discharged to the exhaust port 14 gathers in the exhaust manifold 24 connected to the exhaust ports 14 of a plurality of cylinders by branch pipes, and then is connected to a supercharger 35, a deodorizing and denitrating device 36, a boiler 37, and a silencer. The exhaust gas processing device such as 38 is sequentially passed and released to the atmosphere.
The deodorization / denitration device 36 is a device that removes odor components and nitrogen oxides using an adsorbent or a catalyst. In addition, the piping connecting each device is provided with a safety valve so that if an unexpected high pressure is applied, the rupture plate is broken and high pressure gas is released to the outside air so that excessive pressure is not applied to the devices.

The gaseous fuel is supplied to and held in a gaseous fuel storage device 31 such as a cylinder or tank, is supplied to the regulator 33 via the shutoff valve 32, and is adjusted to an appropriate pressure by the regulator 33 before being supplied to the fuel header 25. Supplied. The fuel header 25 includes a branch pipe 28 for each cylinder, and a fuel supply pipe 29 is connected to the tip of the branch pipe 28 via a throttle 34. Providing the throttle 34 has an effect of not significantly affecting the pressure of the fuel header 25 when the gaseous fuel is supplied to the air supply port 13.
The lower end of the fuel supply pipe 29 is connected to the supply port of the fuel supply valve 26, and the gaseous fuel from the header 25 is supplied to the fuel supply valve 26.

  The fuel supply valve 26 is an electromagnetic valve capable of forming a large opening with a small stroke and allowing a large amount of gas to flow in a short time. As shown conceptually in FIG. 2, a valve seat 46 formed of a flat plate, and a valve seat A solenoid-driven face-type poppet valve or the like having a valve body 45 formed of a flat plate that is in contact with the flat surface of the flat plate and blocks the flow path is used. The fuel supply valve 26 that is often used has through-grooves formed concentrically on the flat plate of the valve body 45 and the flat plate of the valve seat 46, respectively. When the valve body 45 and the valve seat 46 are in plane contact, When the through grooves are displaced from each other, the passage is blocked and the valve is closed, and when the valve body 45 and the valve seat 46 are separated from each other, the plurality of through grooves are electrically connected to each other to form a large opening. It is like that. When the valve is opened, the valve body 45 is attracted away from the valve seat 46 by the electromagnet 43, and when the valve is closed, the valve body 45 is pressed against the valve seat 46 by the spring 44.

Further, by adjusting the gaseous fuel in the fuel header 25 to a sufficiently high pressure so that the differential pressure between the fuel pressure and the supply air pressure is about 50 to 200 kPa, a large flow rate can be secured.
Further, the electromagnet 43 that attracts the valve body 45 of the fuel supply valve 26 is strong, and the valve body 45 can be pulled off from the valve seat 46 in a short time to form a large opening. Since the spring 44 that presses against the spring is also strong, the opening and closing of the valve has a quick response of about 2 to 3 ms.
The supply amount of the gaseous fuel can be set with high reproducibility according to the valve opening time of the fuel supply valve 26.
A vibration sensor 51 that detects vibration generated when the valve body 45 and the valve seat 46 collide is fixed to the outer wall of the housing near the valve seat 46 of the fuel supply valve 26.

  Each cylinder is controlled by the engine control device 40. The engine control device 40 includes, for example, an air pressure signal supplied from a pressure transmitter 42 provided in the air supply port 13, a crank angle signal supplied from a rotational phase meter 41 that measures the rotational phase of the crankshaft 21, Then, an index of specifications for measuring the performance of the generator 22 is input to grasp the operation status of the gas engine 10.

Based on this information, the engine control device 40 calculates the current output of the generator 22, compares it with the set target output, and if there is a deviation, sets various control variables so as to eliminate the deviation. adjust. The engine control device 40 can control the air-fuel ratio in the combustion chamber by adjusting the amount of gaseous fuel supplied during supply using the supply air pressure. Further, on the basis of the crank angle, each cylinder has a function of calculating opening / closing timings of the spark plug 19, the air supply valve 15, the exhaust valve 16, the fuel supply valve 26, etc., and issuing an operation command thereto.
Note that the engine control device 40 can perform an emergency stop of the engine by giving a valve closing command to the fuel supply valves 26 in all the cylinders when necessary.

The abnormality detection device for the fuel supply valve according to the present embodiment has a function of detecting an abnormality of the fuel supply valve 26 during operation.
The fuel supply valve 26 includes a valve seat 46 formed of a flat plate and a valve body 45 formed of a flat plate that contacts a flat surface of the flat plate of the valve seat 46 and blocks a flow path, and is extremely small, less than 0.3 mm. Switch between opening and closing with a stroke.
For this reason, even if a very small foreign object is inserted, the flat surface of the valve body 45 and the flat surface of the valve seat 46 cannot be closed closely, resulting in poor valve closing, and a large amount of gaseous fuel leaks and is supplied. Mix in the air.

If an abnormality occurs in which gas leaks to the fuel supply valve 26, the gas concentration of the air-fuel mixture in the combustion chamber shifts to a richer side than the combustible range and no explosion occurs, or the unburned air-fuel mixture flows down to the exhaust manifold 24. When the exhaust gas from other cylinders is collected and mixed with unburned oxygen in the exhaust gas, the air-fuel ratio of the air-fuel mixture in the exhaust manifold 24 may enter the combustible range.
Further, even after the air supply valve 15 is closed, gaseous fuel is supplied due to leakage, and a fuel rich mixture is generated at the air supply port 13, so that this air-fuel mixture becomes the next air supply stroke. Even if it is supplied to the combustion chamber, it is not combusted but is discharged to the exhaust port 14, and when it collects with exhaust gas from other cylinders in the exhaust manifold 24, there is a possibility that an air-fuel mixture in the combustible range is continuously generated. .

When surplus energy is released when the air-fuel mixture in the exhaust manifold 24 is in the combustible range and ignites and burns, the structure of the supercharger 35 existing downstream of the exhaust manifold 24, the adsorbent of the deodorization and denitration device 36, There is a risk of damaging the catalyst, the heat exchanger of the boiler 37, the structure of the silencer 38, and the like.
If these devices are damaged, a large-scale repair work is required, resulting in a great damage.

For this reason, in this embodiment, when a gas leak occurs when the fuel supply valve 26 is closed, an abnormality detection device that immediately detects and informs the gas leakage is transmitted to the engine control device 40. Thus, it is possible to take a predetermined emergency stop measure, etc., or to take appropriate measures such as an emergency stop of the engine based on advanced judgment by informing the operator.
The abnormality detection device according to the present embodiment includes a vibration sensor 51 installed on the fuel supply valve 26, a rotation phase meter 41 that functions as a cycle phase signal supply device that supplies a signal indicating the opening / closing timing of the fuel supply valve 26, and a vibration sensor. An abnormal transmission that inputs a vibration measurement signal supplied from 51 and an opening / closing timing display signal of the fuel supply valve 26, determines an abnormality of the fuel supply valve 26 based on vibration accompanying opening and closing of the fuel supply valve 26, and outputs an abnormal signal Device 50.

FIG. 3 is a partially cutaway front view for explaining the position where the vibration sensor 51 for measuring vibration accompanying opening and closing of the fuel supply valve 26 is installed.
A fuel supply pipe 29 for supplying gaseous fuel from the fuel header 25 is connected to the inlet of the fuel supply valve 26. The outlet of the fuel supply valve 26 opens to the air supply port 13, and gaseous fuel is injected and mixed into the air supply of the air supply port 13 when the fuel supply valve 26 is open. . The gaseous fuel can be metered and supplied during supply according to the opening period of the fuel supply valve 26.

Here, the vibration sensor 51 is attached to a side wall near the valve seat position of the fuel supply valve 26, and a magnetic core of the valve body 45 and the electromagnet 43 generated by opening and closing of the valve, and the valve body 45 and the valve seat 46 are provided. The vibration at the time of collision is measured, and the vibration measurement signal is transmitted to the abnormality transmitter 50.
However, the engine generates large and small vibrations, and the vibration that can be used to determine an abnormality in the fuel supply valve 26 is only the vibration when the valve body 45 of the fuel supply valve 26 and the valve seat 46 collide. Moreover, the vibration generated by the collision between the valve body 45 and the valve seat 46 has a small stroke and is not necessarily large.

  Therefore, the signal processing device provided in the abnormality transmission device 50 extracts only vibrations synchronized with the occurrence timing of the collision from the vibration measurement signals input from the vibration sensor 51, thereby accompanying the opening and closing of the fuel supply valve 26. After classifying signals representing vibrations, changes in the vibration level are evaluated to detect foreign object biting.

FIG. 4 is a graph for explaining the principle of a method for treating vibration associated with opening and closing of the fuel supply valve 26.
The graph shows time on the horizontal axis, and the vertical graph shows the opening / closing timing of the fuel supply valve on the vertical axis. The graph shows the change in normal vibration intensity in the middle. In the graph conceptually showing the change in vibration intensity at the time of abnormality displayed in the lower row, the acceleration level detected by the vibration sensor, that is, the vibration intensity is displayed on the vertical axis.

The vibration intensity displayed in FIG. 4 represents only the intensity of vibration associated with opening and closing of the fuel supply valve 26 for convenience of explanation. In practice, a time filter in which the window is opened only for an appropriate period before and after the valve opening command signal and the valve closing command signal are generated for the fuel supply valve 26 is opened and closed from the output signal of the vibration sensor 51. It is possible to extract the intensity of vibration associated with. The valve opening command signal and the valve closing command signal are calculated based on the rotational phase of the crankshaft 21 detected by the engine control device 40 with the rotational phase meter 41 and supplied to the fuel supply valve 26. By merely supplying the device 50 to the device 50, a time filter having a duration of vibration can be generated by knowing the timing at which the abnormality transmitter 50 has opened and closed the valve.
Further, the output signal of the rotation phase meter 41 is supplied directly or via the engine control device 40 to the abnormality transmission device 50, and the abnormality transmission device 50 itself generates the time filter based on the rotation phase of the crankshaft. Also good.

  When the fuel supply valve 26 is normal, the vibration at the time of opening and closing of the fuel supply valve 26 is repeatedly generated with substantially the same strength. On the other hand, when the valve is closed with foreign matter sandwiched between the valve body 45 and the valve seat 46, a buffer is present between the surfaces of the valve body 45 and the valve seat 46 that collide with each other. Therefore, the intensity of vibration and noise generated by the collision between the valve body 45 and the valve seat 46 is reduced. The vibration state when the magnetic body of the valve body collides with the magnetic core of the electromagnet 43 with the opening of the fuel supply valve 26 does not change much.

  Therefore, it is possible to determine that the foreign object has been caught when the vibration intensity becomes weaker than normal, paying attention to the vibration when the valve is closed. The weakening of the vibration intensity can be detected by comparing with the vibration level at the time of closing the valve. Also, an appropriate threshold value is found in advance, and it can be determined that an abnormality has occurred in the fuel supply valve 26 when the vibration intensity becomes smaller than the threshold value. When an abnormality is detected, an abnormality alarm signal is transmitted.

This determination procedure is simple, but if an abnormality occurs in the fuel supply valve 26, the abnormality can be detected almost simultaneously with the start of leakage of gaseous fuel. There is room for taking appropriate measures.
If the abnormality transmission device 50 supplies a signal for notifying the occurrence of abnormality when the abnormality is detected to the engine control device 40 so that the engine control device 40 immediately takes an emergency stop, the air-fuel mixture in the exhaust manifold 24 can be obtained. No combustion occurs, and it is possible to prevent damage to each device in the exhaust gas treatment process.
Also, the alarm signal generated by the abnormality transmission device 50 is not directly supplied to the engine control device 40, but the abnormality transmission device 50 notifies the occurrence of the abnormality, and the operator receives the notification and receives an appropriate notification via the engine control device 40. You may make it take a countermeasure.

FIG. 5 is a flowchart illustrating the abnormality detection procedure executed by the abnormality detection device for the fuel supply valve 26 as an example.
The abnormality detection device of the present embodiment takes in the information of the cycle phase obtained from the engine control device 40 based on the rotation phase of the crankshaft (S11), and knows the closing timing of the fuel supply valve 26 (S12). The vibration generated in the valve seat 46 when the valve is closed is extracted from the vibration measurement result supplied from the vibration sensor 51 (S13).

The vibration thus extracted is compared with the vibration intensity at the previous valve closing timing (S14). If the vibration intensity falls below the threshold value, it is determined that an abnormality has occurred in the fuel supply valve 26 and an abnormality detection signal is generated. (S15). When the current time is not the closing timing of the fuel supply valve 26 (S12) or when the vibration intensity is higher than the threshold value (S14), the process returns to the first stage (S11) and the next work procedure is started.
The abnormality detection signal may be supplied to the engine control device 40 to start an emergency stop operation. Alternatively, an alarm may be used to determine the operator's judgment.

The procedure shown in FIG. 5 is such that the abnormality transmission device 50 selects the timing for evaluating the vibration of the fuel supply valve 26 based on the phase signal acquired from the engine control device 40. Alternatively, the abnormality transmitter 50 can directly receive the cycle phase information from the rotation phase meter 41 installed on the crankshaft 21. Further, the valve closing command signal for the fuel supply valve 26 supplied from the engine control device 40 can be received and used.
In addition, the abnormality transmission device in the present embodiment may be configured by a dedicated electronic circuit or may be configured by a general-purpose microcomputer. Furthermore, you may make it comprise with a part of electronic circuit which comprises the control apparatus for gas engines.

  In the present embodiment, the invention will be described by taking a four-cycle gas engine having a sub chamber as an example, but the technical idea according to the invention can be applied even if there is no sub chamber or a two-cycle engine. Needless to say, it can be done. Moreover, although the gas engine demonstrated in a figure drives a generator, it may drive a wheel, a screw, etc., and may utilize it for operation of a vehicle or a ship.

  The fuel supply valve abnormality detection device and method in the gas engine according to the present invention detects an abnormality of the fuel supply valve immediately after the occurrence, so that the detection signal is supplied to the control device as it is to make an emergency stop or notify the operator. It is possible to prevent damage to various devices and catalysts in the combustion gas treatment process by promoting appropriate countermeasures and effectively using it in the field of power generation and rotational power using a gas engine. be able to.

DESCRIPTION OF SYMBOLS 10 Gas engine 11 Engine cylinder 12 Piston 13 Supply port 14 Exhaust port 15 Supply valve 16 Exhaust valve 17 Main combustion chamber 18 Subchamber 19 Spark plug 20 Cylinder head 21 Crankshaft 22 Generator 23 Supply manifold 24 Exhaust manifold 25 Fuel Header 26 Fuel supply valve 28 Fuel supply pipe (branch pipe)
29 Fuel supply pipe 31 Gaseous fuel storage device 32 Shut-off valve 33 Regulator 34 Restriction 35 Supercharger 36 Deodorization denitration device 37 Boiler 38 Silencer 40 Engine control device 41 Rotation phase meter 42 Pressure sensor 43 Electromagnet 44 Spring 45 Valve body 46 Valve seat 50 Abnormal transmission device 51 Vibration sensor

Claims (7)

An abnormality detection device that detects an abnormality of a fuel supply valve that supplies gaseous fuel to an intake port in a gas engine,
A vibration sensor installed in the fuel supply valve;
A cycle phase signal supply device for supplying a signal indicating the opening and closing timing of the fuel supply valve;
A vibration measurement signal supplied from the vibration sensor and a signal indicating the opening / closing timing of the fuel supply valve are input to determine a vibration associated with the opening / closing of the fuel supply valve. Based on the determined vibration, the fuel supply valve An abnormality transmission device for judging abnormality and outputting an abnormality signal, An abnormality detection device for a fuel supply valve in a gas engine. The cycle phase signal supply device is an engine control device of the gas engine, and the signal indicating the opening / closing timing of the fuel supply valve is an open / close command signal of the fuel supply valve input from the engine control device. The abnormality detection device for a fuel supply valve in a gas engine according to claim 1. The cycle phase signal supply device is a rotation phase meter that detects the rotation phase of the crankshaft of the gas engine, and the signal that indicates the opening / closing timing of the fuel supply valve is directly from the rotation phase meter or the engine control device. The abnormality detection device for a fuel supply valve in a gas engine according to claim 1, wherein the abnormality detection device is supplied indirectly through a gas engine. 4. The abnormality transmitting device determines that the fuel supply valve is abnormal when vibration associated with opening and closing of the fuel supply valve becomes a value equal to or less than a predetermined threshold value. An abnormality detection device for a fuel supply valve in the gas engine according to the item. 2. The abnormality transmission device determines that the fuel supply valve is abnormal when a vibration associated with opening and closing of the fuel supply valve has decreased to a predetermined value or more as compared with a previous one. The abnormality detection apparatus for the fuel supply valve in the gas engine according to any one of claims 1 to 3. An abnormality detection method for detecting an abnormality in a fuel supply valve that supplies gaseous fuel to an intake port in a gas engine,
When the vibration intensity of the fuel supply valve detected at the opening / closing timing of the fuel supply valve decreases to a predetermined value or less, or when the fuel intensity decreases to a predetermined value or more compared to the previous value, the abnormality of the fuel supply valve An abnormality detection method for a fuel supply valve in a gas engine, characterized in that an abnormality detection signal is output after determination.   A gas engine comprising the fuel supply valve abnormality detection device according to any one of claims 1 to 5.

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