JP5074255B2 - Gas engine control device - Google Patents

Description

  The present invention relates to a gas engine control device, and more particularly to a technique for opening correction control for NOx reduction of a fuel gas supply amount adjusting means provided in a fuel gas supply path that joins an intake path.

  Conventionally, a gas engine is known as an engine that supplies a mixture of air and fuel gas to a combustion chamber. Further, lean combustion control that realizes NOx reduction by controlling the air-fuel ratio of the gas engine to the lean limit is also known. The fuel gas supply amount adjusting valve is a fuel gas supply amount adjusting means provided in the fuel gas supply path in order to control the air-fuel ratio. For example, Patent Document 1 discloses a lean combustion control method in a gas engine control device that adjusts the opening of a fuel gas supply amount adjustment valve so that the variation of the combustion fluctuation value converges to the target fuel fluctuation value.

In the intake path of the gas engine, for example, the intake flow rate decreases due to deterioration over time such as clogging of an air cleaner. For this reason, the fuel gas supply amount adjustment valve needs to correct the opening of the fuel gas supply amount as the intake flow rate decreases. Therefore, the inventors forcibly increase or decrease the opening of the fuel gas supply amount adjustment valve at a predetermined time, and based on the maximum and minimum values of the opening in the convergence process to the target combustion fluctuation value, The opening correction for calculating the opening correction value was performed.
Japanese Patent Application Laid-Open No. 11-200195

  However, the opening degree correction described above is performed in a predetermined engine operating region (engine speed and engine load). Here, since the air-fuel ratio characteristic varies depending on the engine operation region, the control accuracy of the air-fuel ratio may be poor in the engine operation region other than the representative point where the opening degree correction is performed. Therefore, the problem to be solved is that, in the opening correction of the fuel gas supply amount adjustment valve, the opening correction value is developed for each engine operating region based on the air-fuel ratio characteristic for each engine operating region, and the opening correction accuracy Is to improve.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

The engine load detecting means (131) for detecting the engine load, the engine speed detecting means (132) for detecting the engine speed, and the fuel gas supply path (3) for joining the intake path. The fuel gas supply amount adjusting means (35) for adjusting the fuel gas supply amount to the intake passage and the engine speed detection means (132) are provided for a pulse number measurement time corresponding to one combustion cycle. The engine speed (N) is calculated based on the engine speed, and the instantaneous engine speed (n1, n2, n3) is calculated based on the pulse number measurement time corresponding to the combustion stroke for each cylinder in one combustion cycle. the number (N) and the instantaneous engine speed actual combustion variation value based on the rotational speed difference between the (n1, n2, n3) and (PIV), a target combustion variation value based on the engine load ( Opening degree adjusting means (200) for adjusting the fuel gas supply amount adjusting means (35) so as to converge to IVm), and forcibly setting the opening degree of the fuel gas supply amount adjusting means (35) at a predetermined time. An opening correction means (300) that increases or decreases and calculates an opening correction value (GVM_rv) based on the maximum and minimum values of the opening in the process of convergence to the target combustion fluctuation value (PIVm); The correction coefficient based on the air-fuel ratio characteristic for each engine operating region is a rated correction coefficient (ε), and the correction coefficient based on the air-fuel ratio characteristic due to aging deterioration of each engine operating region and the intake passage A correction coefficient (η) is used, and the opening correction value (GVM_rv) is multiplied by the rated correction coefficient (ε) until the number of corrections is less than a predetermined number of corrections. Multiplied by the positive coefficient (eta), those comprising correcting expansion means for expanding each engine operating region (400).

According to a second aspect of the present invention, in the gas engine control device according to the first aspect of the present invention, the gas engine control device includes an intake negative pressure detecting means (133) provided in the intake path for detecting an intake negative pressure in the intake path, and the time correction coefficient ( η) is calculated based on the intake negative pressure .

  As effects of the present invention, the following effects can be obtained.

  According to the first aspect, since the opening correction value is developed for each engine operation region based on the air-fuel ratio characteristic for each engine operation region, the opening correction accuracy of the fuel gas supply amount adjusting valve can be improved.

  In addition, since the opening correction value is developed for each engine operating region based on the air-fuel ratio characteristics due to the aging deterioration of the intake passage for each engine operating region, the opening correction accuracy of the fuel gas supply amount adjustment valve can be improved. it can.

  In addition, since the correction coefficient is properly used according to the usage progress of the gas engine, the opening degree correction accuracy of the fuel gas supply amount adjusting valve can be improved.

According to the second aspect of the present invention, since it is possible to actually measure a decrease in the air flow rate due to aged deterioration of the intake passage, it is possible to improve the opening degree correction accuracy of the fuel gas supply amount adjusting valve.

  Next, embodiments of the invention will be described. 1 is a block diagram showing the configuration of a gas engine control device and a gas engine according to an embodiment of the present invention, FIG. 2 is a block diagram showing the configuration of the gas engine control device, and FIG. 3 is a graph showing the PIV map. is there.

  4 is a block diagram showing the opening adjustment control, FIG. 5 is a flowchart showing the opening correction control, and FIG. 6 is a chart showing the time series change of the opening correction control.

  FIG. 7 is a graph showing a rating correction map, FIG. 8 is a graph showing the correlation between engine output, air-fuel ratio characteristics and aging of the air cleaner, FIG. 9 is a graph showing a time-dependent correction map, and FIG. It is a table figure which shows a pressure map.

  First, the engine 2 that is a control target of the gas engine control device 1 of the present invention will be briefly described with reference to FIG. In this embodiment, the engine 2 is mounted on an engine-driven heat pump. The engine 2 of the present embodiment is a three-cylinder gas engine that uses gaseous fuel such as natural gas, and includes three cylinders including the illustrated cylinder. The engine 2 includes an intake path, a fuel gas supply path, an engine body, and an exhaust path. The intake passage is configured by an intake pipe 11 for supplying mixed gas generated by mixing air and fuel taken from outside and fuel by a mixer 3 described later, and an air cleaner 12 for removing dust and the like contained in the air. Yes. The engine main body opens and closes the combustion chamber 21a, which is a space for burning the mixed gas, and the cylinder head 21, thereby connecting the intake pipe 11 and the combustion chamber 21a to the intake valve 23 and the combustion chamber 21a. The spark plug 22 that generates sparks to burn the supplied mixed gas, the mixed gas supplied to the combustion chamber 21a burns and expands, and the piston 25 slides in the vertical direction by the reciprocating motion of the piston 25. A crankshaft 26 that rotates and an exhaust valve 24 that opens or closes the exhaust pipe 13 and the combustion chamber 21a by performing an opening / closing operation in the cylinder head 21 are provided. The exhaust path is configured by an exhaust pipe 13 that exhausts the exhaust gas generated by the combustion of the mixed gas in the combustion chamber 21 a to the outside of the engine 2.

  The mixer 3 as a fuel gas supply path includes a first fuel supply pipe 31 that supplies fuel gas into the intake pipe 11, an open / close fuel valve 32 that temporarily increases the fuel gas from the first fuel supply pipe 31, and an open / close Gas for adjusting the amount of fuel gas passing through the second fuel supply line 34, that is, the amount of fuel gas contained in the mixed gas, bypassing the fuel valve 32 and connected to the first fuel supply line 31 A differential pressure is generated between the fuel gas and the intake air in the fuel gas supply amount adjustment valve 35 and the first fuel supply pipe 31 as the supply amount adjusting means, and the fuel gas is supplied from the first fuel supply pipe 31 to the intake pipe. 11 and a throttle valve 36 that adjusts the supply amount of the mixed gas. Note that the open / close fuel valve 32 is omitted when the control for temporarily increasing the fuel gas is not incorporated.

Next, the gas engine control device 1 will be described in detail with reference to FIGS. 1 and 2.
As shown in FIGS. 1 and 2, the gas engine control device 1 mainly includes a fuel gas supply amount adjustment valve 35, an engine speed sensor 132, a high pressure sensor 131, an intake negative pressure sensor 133, and an Electronic Control Unit that performs various calculations. (Hereinafter referred to as ECU) 150 and the like. The engine speed sensor 132 as an engine speed detection means is a sensor that can measure a pulse signal for each predetermined angle of a gear that rotates in synchronization with the crankshaft 26. In the present invention, the engine speed N is calculated based on the pulse number measurement time corresponding to one combustion cycle (two rotations of the crankshaft 26). On the other hand, the instantaneous engine speeds n1, n2, and n3 of the cylinder are calculated based on the pulse number measurement time corresponding to the combustion stroke for each cylinder. The high-pressure sensor 131 as engine load detecting means detects the discharge pressure (high-pressure HP) of the compressor of the engine-driven heat pump. And the adiabatic compression work of the refrigerant | coolant by the compressor which is not shown in figure is calculated. As the engine load detection means, the engine coolant temperature, the engine lubricating oil temperature, and the pressure may be detected and calculated from the correlation between these and the load. The intake negative pressure sensor 133 as an intake negative pressure detection means is a sensor that is provided between the air cleaner 12 and the venturi 33 in the intake path and detects the intake negative pressure P in the intake path. The ECU 150 includes a controller 100 having functions as an opening degree adjusting unit 200, an opening degree correcting unit 300, and a correction expanding unit 400, which will be described later, and a storage unit 120.

  The PIV map 50 representing the combustion fluctuation value will be described in detail with reference to FIG. The PIV map 50 is a plot of the target combustion fluctuation value PIVm corresponding to the target lean combustion region corresponding to the engine speed N and the engine load L. Here, the PIV map 50 is a map stored in advance in the storage unit 120 included in the ECU 150. Here, the closer the fuel supply amount of each cylinder is to the stoichiometric air-fuel ratio, the smaller the difference in engine speed N between the engine speed N and the instantaneous engine speed n1, n2, n3 in the combustion stroke of that cylinder. There is a correlation that the number difference becomes large, and a function based on this rotational speed difference is used as a combustion fluctuation value. That is, as the combustion fluctuation value is larger, the NOx generation amount can be reduced in the lean combustion region (however, misfire is likely to occur), and as the combustion fluctuation value is smaller, the NOx generation amount is closer to the stoichiometric air-fuel ratio. It ’s difficult. The target combustion fluctuation value PIVm is selected so as to correspond to a lean combustion region near the limit where no misfire occurs.

  Here, the opening adjustment control will be described in detail with reference to FIG. The controller 100 has a function of performing opening degree adjustment control of the fuel gas supply amount adjusting valve 35 as the opening degree adjusting means 200. A target engine speed setting unit (Nm calculation unit) 102, a target combustion fluctuation value calculation unit (PIVm calculation unit) 103, an opening degree calculation unit (GVM calculation unit) 101, and a combustion fluctuation value calculation unit (PIV calculation unit) 105 These are the functions of the controller 100 as the opening degree adjusting means 200. First, the Nm calculation unit 102 calculates the target engine speed Nm based on the engine load L that is the adiabatic compression work of the refrigerant in the compressor calculated based on the high pressure HP. Next, the PIVm calculation unit 103 calculates a target combustion fluctuation value PIVm from the PIV map 50 of the storage unit 120 based on the target engine speed Nm and the engine load L. On the other hand, the PIV calculation unit 105 calculates an actual combustion fluctuation value PIV based on the difference in engine speed between the engine speed N and the instantaneous engine speed n1, n2, and n3 in the combustion stroke of each cylinder. Here, the GVM calculating unit 101 has a function of calculating a fuel gas supply amount adjusting valve opening GVM (hereinafter referred to as opening GVM) from the deviation ΔPIV. Here, the deviation ΔPIV is a deviation between the target combustion fluctuation value PIVm and the actual combustion fluctuation value PIV.

  Here, the opening degree correction control will be described in detail with reference to FIGS. 5 and 6. The controller 100 has a function of performing opening degree correction control of the fuel gas supply amount adjusting valve 35 as the opening degree correcting means 300.

  First, S110 to S150 will be described in detail with reference to FIG. In the following opening degree correction control, the engine speed N is fixed at a predetermined speed. First, the controller 100 determines whether or not the accumulated operation time of the engine 2 has reached a predetermined time t_int (S110). Here, the predetermined time t_int is an accumulated operation time that is calculated from the installation on site or after the maintenance. Next, when the integrated operation time reaches the predetermined timing t_int, the controller 100 forcibly increases the opening degree GVM by a predetermined amount to the opening degree command value by the GVM calculation unit 101 (S120), and the number of samplings n and the number of extreme values The setting of m is set to 1 (S130). Here, the sampling number n represents the number of times the opening degree GVM is sampled from the start of the opening degree correction control. That is, GVM (n) is the opening degree GVM sampled by the controller 100 for the nth time. Further, the number of extreme values m represents the number of extreme values from the start of the opening degree correction control when the extreme value to be detected when the local maximum value and the local minimum value are combined into the extreme value. When the opening degree GVM is forcibly increased at the beginning of the control as in this embodiment, that is, when the fuel gas is increased and the initial value of the extreme value number m is set to 1, the opening degree is obtained when the extreme value number m is an odd number. A minimum value of GVM appears, and a maximum value of opening degree GVM appears when the value is even. When the opening GVM is forcibly reduced by a predetermined amount, that is, when the fuel gas is reduced and the initial value of the extreme value m is set to 1, the maximum value of the opening GVM is obtained when the extreme value m is an odd number. Appears, and when it is an even number, the minimum value of the opening degree GVM appears. Next, the controller 100 calculates the actual combustion fluctuation value PIV (S140) by the opening degree adjusting means 200 as described above, and calculates the opening degree GVM (n) so as to converge to the target combustion fluctuation value PIVm ( S150).

  Here, the time series change of the opening degree GVM and the actual combustion fluctuation value PIV in the opening degree correction control will be described in detail with reference to FIG. In FIG. 6, the horizontal axis represents time (s), the vertical axis below the actual combustion fluctuation value PIV, and the vertical axis above the opening GVM. In FIG. 6, the solid line represents the time series change of the opening degree GVM, and the broken line represents the time series change of the actual combustion fluctuation value PIV and the target combustion fluctuation value PIVm. In S120, since the opening degree GVM is forcibly increased by a predetermined amount, the actual combustion fluctuation value PIV rapidly decreases. The controller 100 decreases the opening degree GVM so as to return the actual combustion fluctuation value PIV that rapidly decreases to the target combustion fluctuation value PIVm. In this way, the opening degree GVM and the actual combustion fluctuation value PIV are repeatedly increased and decreased to converge toward the target combustion fluctuation value PIVm. The opening correction control is a control that performs opening correction based on the maximum value and the minimum value of the opening GVM at this time.

  Next, S210 to S360 will be described in detail with reference to FIG. In S210 to S360, the controller 100 calculates two local maximum values GVMmax1 and GVMmax2 and local minimum values GVMmin1 and GVMmin2 for the opening GVM (n) after the opening GVM is forcibly increased by a predetermined amount (see FIG. 6). ). S210 is a step of determining whether GVM (n) to be determined is a process toward a minimum value or a process toward a maximum value. As described above, if the extreme value number m is an odd number, the GVM (n) to be determined is a minimum value, and if the extreme value number m is an even number, it is a maximum value. S220 is a step of determining whether GVM (n) is greater than GVM (n-1), that is, whether it is a minimum value. S250 is a step of determining whether GVM (n) is smaller than GVM (n-1), that is, a maximum value. S240 and S270 are steps for increasing the number of samplings n and returning to S140 again until GVM (n) reaches the minimum and maximum values. S230 and 260 are steps for determining whether the maximum value (or minimum value) is first or second from the start of the opening degree correction control. S310 and 320 are steps in which the current GVM (n) is set to the first minimum value GVMmin1 and the second minimum value GVMmin2. On the other hand, S330 and 340 are steps in which the current GVM (n) is set to the first maximum value GVMmax1 and the second maximum value GVMmax2. S350 is a step of increasing the number m of extreme values by 1 when a local maximum value (or local minimum value) is detected. S360 is a step in which it is determined whether the number of extreme values m is greater than 4, and if it is greater than 4, the detection of extreme values is terminated, and the process proceeds to S410. That is, the extreme value detection step started from S130 is ended when the local minimum value and the local maximum value are detected twice.

  Next, S410 to S430 will be described in detail with reference to FIG. First, the controller 100 calculates the average maximum value GVMmax from the average of the maximum values GVMmax1 and GVMmax2 (S410). At the same time, the controller 100 calculates the average minimum value GVMmin from the average of the minimum values GVMmin1 and GVMmin2 (S410). Next, the controller 100 calculates the internal value of W vs. 1-W of the average minimum value GVMmin and the average maximum value GVMmax as the opening degree update value GVM_rn using the weighting factor W (S420). Next, the controller 100 calculates an opening correction value GVM_rv obtained by subtracting the opening update value GVM_rn calculated in the previous opening correction control from the opening update value GVM_rn (S430). The opening update value GVM_rn is an absolute amount, and the difference from the previous update value is used as the current update value.

  In this way, by forcibly increasing or decreasing the opening degree GVM of the fuel gas supply amount adjustment valve 35, the maximum values GVMmax1 and GVMmax2 and the minimum values GVMmin1 and GVMmin2 of the opening degree GVM can be determined in a short time. In addition, the calculation accuracy of the opening correction value GVM_rv can be improved. That is, the opening degree correction for maintaining the lean combustion of the fuel gas supply amount adjusting valve 35 can be performed in a short time and accurately without using an exhaust pressure sensor or the like. Further, since the actual combustion fluctuation value PIV can be converged to the target combustion fluctuation value PIVm regardless of the reduction of the intake flow rate due to the aging deterioration of the intake passage, the NOx generation amount can be reduced. Furthermore, by limiting the maximum value and the minimum value used for calculating the correction value to detection twice each, optimal control can be executed in order to achieve both time reduction and accuracy improvement. Further, by weighting the average minimum value GVMmin or the average maximum value GVMmax, it is possible to select lean combustion emphasis that weights the average minimum value GVMmin or misfire prevention importance that weights the average maximum value GVMmax.

<About correction development control>
Hereinafter, the correction development control will be described in detail with reference to FIGS. The controller 100 has a function of performing the correction expansion control that expands the above-described opening correction value GVM_rv for each engine operation region based on the air-fuel ratio characteristics as the correction expansion means 400.

<Rated correction map>
First, a rating correction map f (N, L, ε) as a rating correction coefficient will be described with reference to FIG. As shown in FIG. 7, the rating correction map f (N, L, ε) is a three-dimensional map of the engine speed N, the engine load L, and the rating correction coefficient ε. FIG. 7 shows rated correction coefficients ε1,..., Ε4 (hereinafter simply referred to as ε) for each engine operating region, with the horizontal axis representing the engine speed N and the vertical axis representing the engine load L. PIVpoint in FIG. 7 is a predetermined engine speed and a predetermined engine load at which the above-described opening correction control is performed. Here, the air-fuel ratio characteristic of the engine 2 varies depending on the engine speed N and the engine load L, which are engine operating ranges. Therefore, if the opening correction value GMV_rv calculated by PIVpoint is developed in the entire engine operation region, an error such as a large or small correction value occurs depending on the engine operation region. Therefore, it is necessary to multiply the opening correction value GMV_rv by the rated correction coefficient ε based on the air-fuel ratio characteristic for each engine operating region of the engine 2 and develop it for each engine operating region. The rating correction coefficient ε is obtained in advance by experiments, and the rating correction map f (N, L, ε) is stored in the storage unit 120 in advance. In the present embodiment, the individual value of each rating correction coefficient ε in the rating correction map f (N, L, ε) is not particularly limited.

<Aging and O2 concentration>
Here, the correlation between the aging of the air cleaner 12 and the air-fuel ratio characteristic will be described with reference to FIG. Note that the aging deterioration of the air cleaner 12 is a main factor of the aging deterioration of the intake passage. In addition, aged deterioration of the intake path is a factor of a decrease in intake flow rate. In FIG. 8, a solid line A represents a new air cleaner 12A, a broken line B represents an air-fuel ratio characteristic due to an output of the aged air cleaner 12B, and an alternate long and short dash line C represents an air-fuel ratio characteristic due to an output of the aged air cleaner 12C. It is assumed that the air cleaner 12C is significantly deteriorated over time than the air cleaner 12B. FIG. 8 shows the result of measuring the O2 concentration contained in the exhaust gas in each case with an exhaust gas analyzer with the horizontal axis as the output and the vertical axis as the O2 concentration difference, with the air cleaners 12A, 12B, and 12C attached to the engine 2. It is. The engine output represents the engine output of the engine 2 to which the air cleaner is attached. The O2 concentration difference is a difference in O2 concentration between the air cleaners 12B and 12C and the air cleaner 12A. As is apparent from FIG. 8, when the engine output is small, the O2 concentration becomes light if the air cleaner 12 deteriorates over time. On the other hand, when the engine output is large, the O2 concentration increases as the air cleaner 12 deteriorates over time. That is, the air-fuel ratio characteristic due to aging of the air cleaner 12 and the engine output have a correlation.

<Time correction map>
Here, the temporal correction map f (N, L, η) as the temporal correction coefficient will be described with reference to FIG. As shown in FIG. 9, the temporal correction map f (N, L, η) is a three-dimensional map of the engine speed N, the engine load L, and the temporal correction coefficient η. FIG. 9 shows time-dependent correction coefficients η1,..., Η4 (hereinafter simply referred to as η) with the engine speed N as the horizontal axis and the engine load L as the vertical axis. Here, as described above, the air-fuel ratio characteristic of the engine 2 varies depending on the engine operating region. Further, as described in the explanation of FIG. 8, the air-fuel ratio characteristic for each engine operation region varies depending on the aging of the air cleaner 12. Therefore, when the opening correction value GMV_rv at PIVpoint is developed in the entire engine operation region, an error such as a large or small correction value occurs depending on the engine operation region. Therefore, it is necessary to multiply the opening correction value GMV_rv for each engine operation region by each engine operation region and for each engine operation region by multiplying the opening correction value GMV_rv by the time correction coefficient η based on the air-fuel ratio characteristic due to the aging of the air cleaner 12. The temporal correction coefficient η is obtained in advance by experiments, and the temporal correction map f (N, L, η) is stored in the storage unit 120 in advance. In the present embodiment, the individual value of each temporal correction coefficient η in the temporal correction map f (N, L, η) is not particularly limited.

<Correction development control>
Here, the correction development control using the above-described rated correction map f (N, L, ε) and the temporal correction map f (N, L, η) will be described. For easy understanding, the opening degree adjustment control by the opening degree adjusting means 200 is defined as an opening degree map f (N, L, GVM). That is, the opening degree GVM is calculated from the opening degree map f (N, L, GVM) based on the engine speed N and the engine load L. Here, in the opening degree correction control described above, the opening degree map f (N, L, GVM) corrected for the r-th time is set as an updated opening degree map f (N, L, GMV_rn (r)), and up to the r-th time. If the total opening correction amount is a total correction amount map f (N, L, GMV_rv (r)), the relationship between these maps can be expressed as follows.
f (N, L, GMV_rn (r)) = f (N, L, GVM) + f (N, L, GMV_rv (r))
Here, the total opening degree correction amount map f (N, L, GMV_rv (r)) uses the above-described rated correction map f (N, L, ε) and the temporal correction map f (N, L, η), It can be expressed as follows:
f (N, L, GMV_rv (r)) = GMV_rv (1) × f (N, L, ε) + f (N, L, η) × GMV_rv (2) +... + f (N, L, η) × GMV_rv (r)
That is, for the first opening correction value GMV_rv (1), the rated correction map f (N, L, ε) is used for the second and subsequent opening correction values GMV_rv (2) to GMV_rv (r). Multiply by the time correction map f (N, L, η) and the total opening correction amount map f (N, L, GMV_rv (r)), and develop each engine operation region. Note that the timing at which the time-dependent correction map f (N, L, η) is multiplied is not particularly limited to the present embodiment. In this way, the fuel gas supply amount adjustment is performed in order to develop the opening correction value GMV_rv for each engine operating region by multiplying the rated correction map f (N, L, ε) based on the air-fuel ratio characteristics for each engine operating region. The opening degree correction accuracy of the valve 35 can be improved. Further, the fuel gas is used to develop the opening correction value GMV_rv for each engine operating region by multiplying the time-dependent correction map f (N, L, η) based on the air-fuel ratio characteristic due to the aging deterioration of the intake passage for each engine operating region. The opening degree correction accuracy of the supply amount adjusting valve 35 can be improved. Further, in the first and second and subsequent correction development controls, the rated correction map f (N, L, ε) or the temporal correction map f (N, L, η) is used properly according to the usage progress of the engine 2. The opening degree correction accuracy of the fuel gas supply amount adjusting valve 35 can be improved.

<Intake negative pressure map>
Further, another control example of the correction development control will be described with reference to FIG. As shown in FIG. 10, the intake negative pressure map f (P, f (N, L, η)) is an air cleaner for each intake negative pressure P1,. 12 is a two-dimensional map including a plurality of temporal correction maps f1 (N, L, η),..., Fm (N, L, η) corresponding to twelve aging degradations. The intake negative pressure map f (P, f (N, L, η)) is stored in the storage unit 120 in advance. Here, the intake negative pressure P represents the aging deterioration of the intake passage mainly due to the aging deterioration of the air cleaner 12. Therefore, in this control, the time-dependent correction map fm (N, L, η) corresponding to the intake negative pressure P from the intake negative pressure map f (P, f (N, L, η)) based on the current intake negative pressure P. ) Can be calculated. In this way, since the intake negative pressure sensor 133 can actually measure a decrease in the air flow rate in the intake path due to the deterioration of the air cleaner 12 over time, the opening degree correction accuracy of the fuel gas supply amount adjustment valve 35 can be improved.

The block diagram which shows the structure of the gas engine control apparatus which concerns on the Example of this invention, and a gas engine. The block diagram which similarly shows the structure of a gas engine control apparatus. The graph figure which similarly shows a PIV map. The block diagram which similarly shows opening degree adjustment control. The flowchart which similarly shows opening degree correction control. The chart figure which shows the time-sequential change of opening degree correction control similarly. The graph figure which shows a rating correction map. The graph which shows correlation with an engine output, an air fuel ratio characteristic, and aged deterioration of an air cleaner. The graph which shows a time-dependent correction map. The table figure which shows an intake negative pressure map.

DESCRIPTION OF SYMBOLS 1 Gas engine control apparatus 2 Engine 3 Mixer 12 Air cleaner 35 Fuel gas supply amount adjustment valve 50 PIV map 100 Controller 120 Memory | storage part 150 Electronic Control Unit (ECU)
200 Opening adjustment means 300 Opening correction means N Engine speed L Engine load PIV Actual combustion fluctuation value PIVm Target combustion fluctuation value GVM Fuel gas supply amount adjustment valve opening degree (opening degree)
n Number of samplings m Number of extreme values P Intake negative pressure GVMmax1 Maximum value GVMmax2 Maximum value GVMmax Average maximum value GVMmin1 Minimum value GVMmin2 Minimum value GVMmin Average minimum value W Weighting factor GVM_rn Opening correction value GVM_r Opening value correction value GVM_r N, L, ε) Rated correction map η Temporal correction coefficient f (N, L, η) Temporal correction map f (N, L, GVM) Opening map f (N, L, GVM_rn (r) Update opening map f (N, L, GMV_rv (r)) Total correction amount map f (P, f (N, L, η)) Intake negative pressure map

Claims (2)

Engine load detecting means (131) for detecting engine load;
Engine speed detecting means (132) for detecting the engine speed;
A fuel gas supply amount adjusting means (35) that is provided in the fuel gas supply route (3) that joins the intake passage and adjusts the fuel gas supply amount to the intake passage;
The engine speed (N) is calculated based on the pulse number measurement time corresponding to one combustion cycle via the engine speed detecting means (132), and the number of pulses corresponding to the combustion stroke for each cylinder in one combustion cycle. Based on the measured time, the instantaneous engine speed (n1, n2, n3) is calculated, and the actual combustion fluctuation value based on the speed difference between the engine speed (N) and the instantaneous engine speed (n1, n2, n3). An opening degree adjusting means (200) for adjusting the fuel gas supply amount adjusting means (35) so as to converge (PIV) to a target combustion fluctuation value (PIVm) based on the engine load;
At a predetermined time, the opening degree of the fuel gas supply amount adjusting means (35) is forcibly increased or decreased, and based on the maximum value and the minimum value of the opening degree in the process of convergence to the target combustion fluctuation value (PIVm). An opening correction means (300) for calculating an opening correction value (GVM_rv);
In a gas engine control device having
The correction coefficient based on the air-fuel ratio characteristics for each engine operating region is set as a rated correction coefficient (ε), the correction coefficient based on the air-fuel ratio characteristics due to aging of the engine operating region and the intake passage is set as a time-dependent correction coefficient (η), The opening correction value (GVM_rv) is multiplied by the rated correction coefficient (ε) until less than the predetermined number of corrections, and is multiplied by the time-dependent correction coefficient (η) after the predetermined number of corrections to be developed for each engine operating region. A gas engine control device comprising correction expansion means (400) . 2. The gas engine control device according to claim 1, further comprising an intake negative pressure detecting means (133) provided in the intake path for detecting an intake negative pressure in the intake path, wherein the time correction coefficient (η) A gas engine control device calculated based on a negative pressure .