JP5793043B2 - Gas engine equipment - Google Patents

Description

  The present invention relates to a gas engine device.

  Conventionally, a mixer, a turbocharger, and an intercooler are mounted on a so-called gas engine device that generates power using fuel gas such as natural gas. In this case, the combustion gas and air are mixed and stirred by a mixer, and the obtained mixed gas is compressed by a compressor of a turbocharger. Then, after the mixed gas, which has become high temperature and high pressure due to compression, is cooled by an intercooler, the mixed gas having a higher density is supplied to each cylinder of the gas engine via the intake throttle valve. In this way, the charging efficiency of the mixed gas in each cylinder is increased, and the combustion efficiency of the gas engine is improved (see, for example, Patent Document 1).

JP-A-7-91319

  By the way, in this type of gas engine device, for example, when the output of the gas engine suddenly decreases due to some reason, the opening of the intake throttle valve rapidly decreases (the intake throttle valve is suddenly closed and operated). To do). If it does so, the supercharging pressure of the compressor in a turbocharger will raise abnormally, and surging (pulsation) will generate | occur | produce in a turbocharger by the reverse flow of a partial mixed gas. The occurrence of the surging destroys the pressure balance around the mixer, causes an abnormality (riching) in the air-fuel ratio that is the ratio of the intake mass to the fuel mass, and causes abnormal combustion of the gas engine such as knocking. However, the conventional technology has not sufficiently dealt with this type of problem.

  This invention is made | formed in view of the above present conditions, and makes it a technical subject to provide the gas engine apparatus which can suppress the surging generation | occurrence | production in a turbocharger exactly.

A gas engine apparatus according to a first aspect of the present invention includes a gas engine, a turbocharger compressor disposed in a mixed gas path through which a mixed gas to the gas engine passes, and the compressor of the mixed gas path a bypass path connecting the upstream side and the downstream side across and a load detector for detecting a load of the gas engine, the closing valve member for opening and closing the bypass passage, based on a detection result of the load detector A control unit that makes the opening time of the on-off valve member variable, and a surge tank and a throttle part are disposed on the downstream side of the on-off valve member in the bypass path, and the gas engine is disposed on the control unit Open control data corresponding to the relationship between the load change amount of the load and the release time is stored in advance, and the control unit determines whether the change amount obtained from the detection result of the load detection unit From the open control data, it is that determines the opening time of the on-off valve member.

According to a second aspect of the invention, in a gas engine system as set forth in claim 1, wherein the opening control data is a plurality set in accordance with the load of the magnitude of the gas engine, the control unit, the load detector On the basis of the detection result, the opening control data used for determining the opening time is selected.

In general, in a gas engine device, for example, when the load on the gas engine is suddenly reduced for some reason, the opening degree of the intake throttle valve located on the downstream side of the mixed gas path is suddenly reduced, and the compressor of the turbocharger is excessively reduced. The supply pressure is about to rise abnormally. In contrast, in the gas engine according to claim 1 is to change the amount of generated power (the load change of the gas engine obtained from the detection result of the load detector) to trigger the at no small, commensurate with the amount of change The on-off valve member can be opened only during the opening time.

Accordingly, in the gas engine according to claim 1, at the time of abnormal rise of the supercharging pressure, the opening and closing valve member is opened actuated, the mixed gas through the bypass path on the upstream side of the compressor of the mixed gas path Nigaseru Therefore, it is possible to reliably suppress an abnormal increase in the supercharging pressure of the compressor. Therefore, there is an effect of eliminating the occurrence of surging (pulsation) in the turbocharger due to partial reverse flow of the mixed gas.
Furthermore, in the gas engine device according to the first aspect of the present invention, since the surge tank and the throttle portion are provided on the downstream side of the on-off valve member in the bypass path, the mixed gas that has passed through the on-off valve member is surged. There is an advantage that it can be temporarily stored in the tank, and a large amount of mixed gas can be instantaneously extracted from the downstream side of the mixed gas path (downstream side of the compressor) in order to avoid surging. Moreover, since the mixed gas in the surge tank is returned to the upstream side of the mixed gas path (upstream side of the compressor) via the throttle portion, there is also an advantage that the mixed gas can be recirculated without breaking the upstream pressure balance.

In particular, according to the first aspect of the present invention, the control unit stores in advance opening control data corresponding to the relationship between the amount of change in the load of the gas engine and the opening time, and the control unit detects the load detection unit. Since the opening time of the on-off valve member is determined from the change amount obtained from the result and the opening control data, a suitable opening time can be set according to the magnitude of the load applied to the gas engine. Therefore, surging can be effectively prevented in the entire output range (full load range) of the gas engine.

Employing invention 請 Motomeko 2, the opening control data is a plurality set in accordance with the load of the magnitude of the gas engine, the control unit based on the detection result of the load detector, the open Since the opening control data used for time determination is selected, for example, even when there is a small load change, it is possible to control the release of the mixed gas (supercharging pressure) by taking sufficient time for the opening, and control accuracy can be improved. Improvements can be made.

It is a schematic side view of an engine power generator. It is a schematic plan view of an engine power generator. It is an engine intake system diagram. It is a functional block diagram of an engine controller. It is a flowchart of supercharging pressure release control. It is a logic explanatory drawing of supercharging pressure release control, (a) is a figure which shows the switching timing of a circuit breaker, (b) is a figure which shows transition of generated electric power, (c) is a figure which shows opening and closing timing of an opening and closing solenoid valve. It is. In another example of supercharging pressure release control, it is an opening and closing control map showing the relationship between the change amount ΔE and the release time tb. It is a flowchart of another example of supercharging pressure release control. It is logic explanatory drawing of another example, (a) is a figure which shows transition of generated electric power, (b) is a figure which shows the opening / closing timing of an opening-and-closing solenoid valve.

  Hereinafter, an embodiment embodying the present invention will be described with reference to the drawings in a case where the present invention is applied to an engine power generator 1 having an engine 21 and a generator 38.

  First, the structure of the engine power generator 1 will be described with reference to FIGS. The engine power generator 1 includes an engine 21 that is a power source and a generator 38 that generates electric power by driving the engine. The engine 21 of the embodiment is a so-called gas engine that generates power using a fuel gas such as natural gas. The engine 21 includes a cylinder block 22 having an output shaft (also referred to as a crankshaft, not shown), and a cylinder head 23 mounted on the cylinder block 22. An intake manifold 24 is provided on one side of the cylinder head 23, and an exhaust manifold 25 is provided on the other side. A cylinder block 22 of the engine 21 is mounted on the base table 26 via a vibration isolator 27. Accordingly, the engine 21 is supported by the base stand 26 via the vibration isolator 27 in an anti-vibration manner.

  The generator 38 is connected to the tip end side of the output shaft protruding from the cylinder block 22 so that power can be transmitted. The generator 38 is driven to generate power by the constant speed power of the engine 21. The generated power generated by driving the generator 38 is supplied to an arbitrary electric system. In the embodiment, a box-shaped frame frame 39 is provided on the half of the base table 26 opposite to the engine 21. A generator 38 is installed on the inner side of the frame 39.

  An oil pan 28 for storing lubricating oil is disposed on the lower surface of the cylinder block 22 in the engine 21. The lubricating oil in the oil pan 28 is sucked by an oil pump (not shown) that is driven by the rotation of the output shaft, and is supplied to the engine 21 via an oil cooler (not shown) that cools the lubricating oil with engine cooling water. Supplied to each lubrication part. The lubricating oil supplied to each lubricating part is then returned to the oil pan 28. The oil pump and the oil cooler are attached to the cylinder block 22.

  An intercooler 31 is attached to the side surface of the cylinder head 23. The intake side of the intercooler 31 is connected to an air cleaner 34 through the compressor 32a and the mixer 33 of the turbocharger 32 to remove and purify outside air (air around the engine generator 1). A gas supply device 35 for supplying combustion gas is also connected to the mixer 33. The discharge side of the intercooler 31 is connected to the intake manifold 24 via the intake throttle valve 36.

  The mixed gas obtained by mixing and stirring the combustion gas and air with the mixer 33 is compressed by the compressor 32a of the turbocharger 32 and becomes high pressure and high temperature. The high-temperature and high-pressure mixed gas is cooled by the intercooler 31 and then sent to the intake manifold 24 via the intake throttle valve 36 and supplied to each cylinder of the engine 21. In the embodiment, the turbocharger 32 is disposed in the vicinity of the exhaust manifold 25, and the mixer 33 and the air cleaner 34 are provided on the upper surface side of the frame frame 39. A gas supply device 35 is provided on one side of the frame frame 39.

  The turbocharger 32 has the above-described compressor 32a with a built-in blower wheel and an exhaust turbine 32b with a built-in turbine wheel. The intake side of the exhaust turbine 32 b is connected to the exhaust manifold 25 of the engine 21. The exhaust side of the exhaust turbine 32 b is connected to the tail pipe 37. Exhaust gas discharged from each cylinder of the engine 21 to the exhaust manifold 25 is discharged from the tail pipe 37 to the outside via the turbocharger 32.

  Next, the intake system of the engine 21 will be described with reference to FIG. As shown in detail in FIG. 3, one of the two suction sides of the mixer 33 is connected to the air cleaner 34 via the intake path 91, and the other is connected to the gas supply device 35 via the combustion gas path 92. Yes. The discharge side of the mixer 33 is connected to the intake manifold 24 of the engine 21 via the mixed gas path 93. In the mixed gas path 93, the compressor 32a, the intercooler 31, and the intake throttle valve 36 of the turbocharger 32 are provided in this order from the upstream side.

  In the mixed gas path 93, the upstream side and the downstream side across the compressor 32 a and the intercooler 31 are also connected by a bypass path 94 for bypassing these 32 a and 31. The intake side of the bypass path 94 is connected between the intercooler 31 and the intake throttle valve 36 in the mixed gas path 93. The discharge side of the bypass path 94 is connected between the mixer 33 and the compressor 32 a in the mixed gas path 93.

  In the middle of the bypass path 94, an open / close electromagnetic valve 95 is provided as an open / close valve member for releasing the supercharging pressure of the compressor 32a. For example, when the output of the engine 21 is suddenly reduced and the opening of the intake throttle valve 36 is suddenly reduced (rapidly closed), the abnormal increase in the supercharging pressure of the compressor 32a is suppressed by opening the open / close electromagnetic valve 95. As a result, occurrence of surging in the turbocharger 32 is prevented. Note that the open / close electromagnetic valve 95 is normally kept in a closed state (normally closed type).

  A surge tank 96 and a throttle portion 97 are provided downstream of the open / close electromagnetic valve 95 in the bypass path 94. The surge tank 96 temporarily stores the mixed gas that escapes to the upstream side of the compressor 32a. The surge tank 96 according to the embodiment is located between the open / close electromagnetic valve 95 and the discharge side connection portion in the bypass path 94. The restricting portion 97 limits the flow rate of the mixed gas that escapes to the upstream side of the compressor 32a. The throttle part 97 of the embodiment is located downstream of the surge tank 96 in the bypass path 94.

  Next, a structure for executing supercharging pressure release control of the engine 21 will be described with reference to FIGS. As shown in FIGS. 1 and 2, a control panel 100 having an engine controller 101 (see FIG. 4) or the like as a control unit is disposed on the opposite side of the engine 21 across the generator 38. The engine controller 101 in the control panel 100 includes a CPU 102 for executing various arithmetic processes, a ROM 103 for storing control programs and data, a RAM 104 for temporarily storing control programs and data, a clock as a timer function, a sensor and an actuator. Etc., and an input / output interface for exchanging data with each other. The input / output interface of the engine controller 101 includes a power transducer 105 that detects generated power generated by driving the generator 38, a circuit breaker 106 provided between the generator 38 and the supply destination electrical system, and a bypass path 94. An open / close electromagnetic valve 95 or the like in the middle is electrically connected.

  When the engine 21 is in a no-load state by the opening operation (load cutting operation) of the circuit breaker 106, the engine controller 101 opens the open / close solenoid valve 95 for a predetermined opening time to increase the boost pressure of the compressor 32a. The boost pressure release control is performed so as to release to the upstream side. The opening operation of the circuit breaker 106 is used as a trigger for the opening operation of the open / close solenoid valve 95. The power transducer 105 is arranged in the control panel 100 together with the engine controller 101.

  Next, an example of the flow of supercharging pressure release control will be described with reference to FIGS. 5 and 6. Note that the algorithm shown in the flowchart of FIG. 5 is stored as a program in the ROM 103 of the engine controller 101 and is read by the RAM 104 and executed by the CPU 102. Further, data on the opening time to of the open / close solenoid valve 95 when the engine 21 is not loaded and the minimum generated power Emin of the generator 38 corresponding to the minimum drive output of the engine 21 are stored in advance in the ROM 103 of the engine controller 101 or the like. Is set.

  As shown in the flowchart of FIG. 5 and the explanatory diagrams of FIGS. 6A to 6C, the engine controller 101 first reads the current generated power Enow, which is the detection result of the power transducer 105 (S01). Then, when the current generated power Enow is equal to or greater than the minimum generated power Emin (S02: YES), if the circuit breaker 106 is opened (S03: YES), the open / close solenoid valve 95 is opened for the open time to again. Close (S04).

  In the engine power generator 1 equipped with this type of engine 21 and generator 38, when the circuit breaker 106 is opened, the load applied to the engine 21 is suddenly reduced to a no-load state, and the opening degree of the intake throttle valve 36 is increased. Decrease rapidly. Then, the supercharging pressure of the compressor 32a in the turbocharger 32 tends to rise abnormally. In this case, the opening operation of the circuit breaker 106 is used as a trigger to open the open / close solenoid valve 95 for the open time to, Since the mixed gas can escape through the bypass path 94 to the upstream side of the compressor 32a in the mixed gas path 93, an abnormal increase in the supercharging pressure of the compressor 32a can be reliably suppressed. Therefore, it is possible to eliminate the occurrence of surging (pulsation) in the turbocharger 32 due to partial reverse flow of the mixed gas.

  Particularly in this case, since the surge tank 96 and the throttle portion 97 are provided on the downstream side of the open / close electromagnetic valve 95 in the bypass path 94, the mixed gas that has passed through the open / close electromagnetic valve 95 is placed in the surge tank 96. There is an advantage that a large amount of mixed gas can be temporarily stored and a large amount of mixed gas can be instantaneously extracted from the downstream side of the mixed gas path 93 (downstream side of the compressor 32a) to avoid surging. Moreover, since the mixed gas in the surge tank 96 is returned to the upstream side of the mixed gas path 93 (upstream side of the compressor 32a) via the throttle portion 97, the mixed gas can be recirculated without breaking the upstream pressure balance. There is also.

  Next, another example of the supercharging pressure release control of the engine 21 will be described with reference to FIGS. In another example of the supercharging pressure release control, when the supercharging pressure of the compressor 32a is released to the upstream side, the opening time tb of the open / close electromagnetic valve 95 is made variable in accordance with the amount of change ΔE in the generated power. The change amount ΔE of the generated power is the difference between the generated power before the change and the generated power after the change, and corresponds to the load change amount of the engine 21. This is because the power generated by the generator 38 is proportional to the output of the engine 21 (which may be referred to as a load). In another example, the unit of change ΔE is percentage (%). This is because the ratio of the generated power in each state was calculated with the generated power (≈engine 21 output) being 100%. The change amount ΔE of the generated power and the power change speed V are obtained from the detection result of the power transducer 105 and are always calculated.

  The engine controller 101 stores in advance opening control maps M1 and M2 as opening control data indicating the relationship between the change amount ΔE and the opening time tb. This kind of opening control map M1, M2 is obtained by experiments or the like. The release control data is not limited to the map format as in the other examples, and may be a function table, set data (data table), or the like. FIG. 7 is a graph showing the release control maps M1, M2 stored in the engine controller 101. In the graph of FIG. 7, the change amount ΔE is taken on the horizontal axis, and the opening time tb is taken on the vertical axis. In this case, two types of an open control map M1 having a reference line L1 and an open control map M2 having a reference line L2 are prepared according to the magnitude of the generated power (%) before the change. FIG. 10 shows both the opening control maps M1 and M2 together.

  In FIG. 7, the thin solid line of the open control map M1 is the first reference line L1 that is referred to when the generated power before the change is less than 50%, and the thick solid line of the open control map M2 is the generated power before the change. This is the second reference line L2 that is referred to when it is 50% or more. In any case, the opening time tb tends to be longer as the change amount ΔE is larger. The aforementioned value of 50% may be changed arbitrarily. Further, the number of open control maps M1, M2 is not limited to two, and may be three or more. The thin solid line L1 (first reference line) has a gentler gradient than the thick solid line L2 (second reference line). This is because even when the generated power before the change is small and the differential pressure between the downstream side of the compressor 32a and the surge tank 96 is small, a sufficient open time is ensured and the supercharging pressure of the compressor is surely released. This is a measure.

  Next, another example of the supercharging pressure release control will be described with reference to FIGS. Note that data relating to the preset setting time ta, the minimum change amount ΔEmin, and the minimum power change speed Vmin are stored and set in advance in the ROM 103 of the engine controller 101 or the like. Incidentally, in the other example, the set time ta is, for example, about 0.2 to 3 seconds.

  As shown in the flowchart of FIG. 8 and the explanatory diagrams of FIGS. 9A and 9B, the engine controller 101 first reads the current generated power Enow as the detection result of the power transducer 105 (S11), and the read It is determined whether or not the generated power Enow is equal to or greater than the minimum generated power Emin (S12). If the generated power Enow is equal to or greater than the minimum generated power Emin (S12: YES), the generator 38 and thus the engine 21 are in a normal driving state, and then the open control maps M1 and M2 corresponding to the generated power Enow are selected. (S13) Then, it is determined whether or not the power change rate V is equal to or greater than the minimum power change rate Vmin and the change amount ΔE is equal to or greater than the minimum change amount ΔEmin based on the constantly calculated amount of change ΔE and power change rate V. (S14). When both conditions are satisfied (S14: YES), a change amount ΔEta = Enow (first) -Enow (after) after the set time ta has elapsed since the start of the change in the generated power Enow is calculated (S15), and step S13. The release time tb is obtained from the release control maps M1 and M2 selected in step S1 and the change amount ΔEta after the set time ta has elapsed (S16), and the open time after the set time ta has elapsed since the start of the change in the generated power Enow. The open / close solenoid valve 95 is opened for tb and then closed again (S17).

  When the above control is adopted, for example, even if the load on the engine 21 suddenly decreases due to some factor and the opening degree of the intake throttle valve 36 suddenly decreases, the change amount ΔE of the generated power and the power change rate V are used as triggers. The open / close solenoid valve 95 can be opened for an open time tb commensurate with the change amount ΔE. Therefore, as in the case of the supercharging pressure release control described above, the mixed gas is released to the upstream side of the compressor 32a in the mixed gas path 93 via the bypass path 94, and the supercharging pressure of the compressor 32a is abnormal. The increase can be reliably suppressed, and the occurrence of surging (pulsation) in the turbocharger 32 can be eliminated.

  In particular, in another example, since a suitable open time tb can be set according to the magnitude of the generated power Now and therefore the load applied to the engine 21, surging is effectively prevented in the entire output range (full load range) of the engine 21. It becomes possible. Further, a plurality of (two in another example) opening control data M1 and M2 are set according to the load of the engine 21, and the engine controller 101 is the current generated power that is the detection result of the power transducer 105. Since the opening control data M1 and M2 used for determining the opening time tb are selected based on the current, for example, even when there is a small load change, the opening time Tb is sufficiently taken to appropriately release the mixed gas (supercharging pressure). Therefore, the control accuracy can be improved. In another example, it goes without saying that the effects of the surge tank 96 and the throttle portion 97 provided on the downstream side of the open / close electromagnetic valve 95 in the bypass path 94 are effectively exhibited.

  In addition, the structure of each part is not limited to embodiment of illustration, A various change is possible in the range which does not deviate from the meaning of this invention.

21 Engine 32 Turbocharger 32a Compressor 38 Generator 93 Mixed gas path 94 Bypass path 95 Open / close solenoid valve (open / close valve member)
96 Surge tank 97 Restriction part 101 Engine controller (control part)
105 Power transducer (load detector)
106 Circuit breaker

Claims (2)

A gas engine, a turbocharger compressor disposed in a mixed gas path through which a mixed gas to the gas engine passes, and an upstream side and a downstream side of the mixed gas path sandwiching the compressor are connected. a bypass passage, a load detector for detecting a load of the gas engine, and an opening and closing valve member in front Symbol bypass path opening and closing to the opening time of the on-off valve member based on a detection result of the load detector to a variable A control unit ,
A surge tank and a throttle portion are disposed on the downstream side of the on-off valve member in the bypass path,
The control unit stores release control data corresponding to the relationship between the change amount of the load of the gas engine and the release time in advance, and the control unit obtains the change amount obtained from the detection result of the load detection unit. And determining the opening time of the on-off valve member from the opening control data,
Gas engine device. A plurality of the opening control data are set according to the load of the gas engine, and the control unit selects the opening control data used for the opening time determination based on the detection result of the load detecting unit. To
The gas engine device according to claim 1.

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