JP2017025791A - Gas engine generator, control program of the same, recording medium of the same, and control method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control an engine according to the variation of the electric power consumption of a load which receives a power generation output.SOLUTION: A gas engine generator comprises: a mixture adjustment means 6 which produces a mixture containing a fuel gas and adjusts the mixing ratio of the fuel gas in the mixture and a mixture amount to be supplied to an engine 4; a mixer; a detection means 10 for detecting the electric power consumption of a load which receives a power generation output; a current measurement circuit; a voltage measurement circuit; an information table 12 storing at least a mixture amount and a mixture ratio, which correspond to an electric power consumption at every target rotation speed; a mixture ratio table; a control means 14 which drives the engine while setting a mixture amount and a mixture ratio, which are necessary for a target rotation speed, in the mixture adjustment means, and makes renewal to the mixture amount and the mixture ratio corresponding to the electric power consumption while referring to the information table and controls an engine rotation speed to the target rotation speed; and a processor.SELECTED DRAWING: Figure 1

Description

The present invention relates to, for example, engine control of a gas engine generator driven by fuel gas.

  In a gas engine generator that uses a gas engine that uses fuel gas as a drive source, the power generation output depends on the rotational speed of the gas engine. The rotational speed of the gas engine depends on the fuel supply amount and the fuel concentration. The fuel supply is adjusted by the throttle, and the fuel concentration is adjusted by the needle.

  Regarding the power generation system equipped with this gas engine generator, the fuel of the gas engine is controlled according to the power demand of the power system that receives the generator output, and the inertial energy of the gas engine and the generator follows the sudden change in load, It is known to adjust the rotational speed (for example, cited document 1).

It is known that a gas engine is provided with a sub-jat in an auxiliary passage branched upstream from the main jet in the fuel supply passage, and this sub-jat is opened and closed by a negative pressure control valve that operates with negative pressure from an introduction hole provided in the intake passage. (For example, Patent Document 2).

JP-A-2005-245105 No. 8-2460

  By the way, in a system that supplies the power output of a gas engine generator to a power load in place of the system power supply in the event of a power failure of a system power supply such as a commercial power supply, the control that causes the gas engine generator to follow the power generation output as the power load increases or decreases Has been done. In this control, feedback control is performed to feed back the increase / decrease change of the load to the gas engine generator, and a power generation output corresponding to the increase / decrease change of the load can be obtained and the engine speed can be kept constant. Although there is a tracking ability to obtain a power generation output corresponding to a power load, there is a problem that it is not responsive.

  In such control, even when the power output required for the gas engine generator can be predicted from the power load, the control including the process of constantly recalculating the control amount decreases the responsiveness accordingly. There is a problem of end.

In view of the above problems, an object of the present invention is to control an engine by fluctuations in power consumption of a load that receives a power generation output.

  In order to achieve the above object, according to one aspect of the gas engine generator of the present invention, a gas engine generator controlled at an engine speed corresponding to a predetermined frequency, which generates an air-fuel mixture containing fuel gas. The fuel gas mixture ratio in the air-fuel mixture, the air-fuel mixture adjusting means for adjusting the amount of air-fuel mixture supplied to the engine, the detection means for detecting the power consumption of the load that receives the power generation output, and the target speed An information table storing at least the mixture amount and the mixture ratio corresponding to power consumption, an mixture amount and mixture ratio required for a target rotational speed are set in the mixture adjustment means, the engine is driven, and the information Control means may be provided that updates the mixture amount and the mixture ratio corresponding to the power consumption with reference to a table and controls the engine to the target rotational speed.

  In the gas engine generator, the control means drives the engine with the air-fuel mixture amount and the mixture ratio required for a target rotational speed at startup and no load, and after starting the engine, from the information table The mixture amount and the mixture ratio corresponding to the power consumption detected by the detection means are obtained, or the mixture amount and the mixture ratio complementing the mixture amount and the mixture ratio are obtained. The set amount of air-fuel mixture and the mixture ratio may be updated.

  In the gas engine generator, the information table may include the efficiency obtained by the mixture amount and the mixture ratio, and the control means may select the mixture amount and the mixture ratio according to the efficiency.

  In order to achieve the above object, according to one aspect of the control program for a gas engine generator of the present invention, a control to be executed by a computer mounted on the gas engine generator controlled at an engine speed corresponding to a predetermined frequency. A program that receives power consumption information detected from a load that receives power generation output, generates a mixture containing fuel gas, and adjusts the mixture ratio of the fuel gas in the mixture and the amount of mixture supplied to the engine At least the air-fuel mixture amount and the mixture ratio set in the air-fuel mixture adjusting means are stored in the information table in correspondence with the power consumption, and the air-fuel mixture amount and the mixture ratio required for the target rotational speed are stored in the air-fuel mixture adjusting means. The engine is set to drive the engine, and the information table is referenced to update the air-fuel mixture amount and the mixture ratio corresponding to the power consumption. A function of controlling the target rotational speed may be realized by the computer.

  In order to achieve the above object, according to one aspect of the recording medium for a gas engine generator of the present invention, a computer mounted on a gas engine generator controlled at an engine speed corresponding to a system power supply frequency is executed. A recording medium used for execution of a control program, which is set in an air-fuel mixture adjusting unit that generates an air-fuel mixture containing fuel gas and adjusts the mixture ratio of the fuel gas in the air-fuel mixture and the amount of air-fuel mixture supplied to the engine An information table for storing at least the mixture amount and the mixture ratio corresponding to the power consumption of the load may be recorded.

In order to achieve the above object, according to one aspect of a control method for a gas engine generator of the present invention, there is provided a control method for a gas engine generator controlled at an engine speed corresponding to a predetermined frequency, wherein the fuel gas is The mixture gas is generated and the fuel gas in the mixture is mixed, and the mixture amount adjusting means for adjusting the mixture amount to be supplied to the engine is set to at least the mixture amount and the mixture ratio. A step of creating an information table to be stored corresponding to the step, a step of detecting the power consumption of the load that receives the power generation output, and a mixture amount and a mixture ratio required for the target rotational speed are set in the mixture adjustment means. And driving the engine, updating the mixture amount and the mixture ratio corresponding to the power consumption with reference to the information table, and controlling the engine to the target rotational speed. There.

  According to the present invention, the following effects can be obtained.

  (1) The amount of air-fuel mixture supplied to the engine and the mixture ratio of the air-fuel mixture are read from the information table and updated in response to fluctuations in the power consumption of the load receiving the power generation output, and the engine control response to fluctuations in the power consumption of the load Can increase the sex.

  (2) Since the generated power is controlled in response to fluctuations in the power consumption of the load that receives the generated output, a stable generated output can be supplied to the load.

  (3) Since the amount of air-fuel mixture supplied to the engine and the mixture ratio of the air-fuel mixture are adjusted according to fluctuations in the power consumption of the load receiving the power generation output, exhaust sensors and mixture ratio detection means for controlling the mixture ratio Is unnecessary.

(4) Since the amount of air-fuel mixture supplied to the engine and the mixture ratio of the air-fuel mixture are adjusted according to fluctuations in the power consumption of the load that receives the power generation output, AC power output control can be realized with the gas engine generator itself, Installation of inverter control equipment in the gas engine generator can be omitted.

It is a figure which shows an example of the gas engine generator which concerns on one embodiment. It is a flowchart which shows the process sequence of engine control. It is a figure which shows an example of the gas engine generator which concerns on one Example. It is a figure which shows an example of the control system of a gas engine generator. It is a figure which shows an example of a mixer and a mixer drive part. It is a figure which shows the control system of rotation speed. It is a figure which shows a mixing ratio table. It is a figure showing the actual mixture ratio table and actual value which are used for preparation of a mixture ratio table. It is a figure showing the actual measurement mixture ratio table and actual value which are used for preparation of other mixing ratio tables. It is a flowchart which shows the process sequence of rotation speed control.

  FIG. 1 shows an example of a gas engine generator according to an embodiment. The configuration shown in the figure is an example, and the present invention is not limited to such configuration.

  In the gas engine generator 2, a target rotational speed Nf is set by a predetermined frequency f such as a system power supply frequency, and the engine rotational speed N is controlled to the target rotational speed Nf. The gas engine generator 2 includes an engine 4, an air-fuel mixture adjusting means 6, a generator 8, a detecting means 10, an information table 12, and a control means 14.

  The engine 4 is a gas engine using an air-fuel mixture containing the fuel gas G as fuel. The air-fuel mixture adjusting means 6 generates the air-fuel mixture by mixing air Ar with the fuel gas G as an example, and adjusts the mixing ratio of the fuel gas G in the air-fuel mixture and the amount of air-fuel mixture supplied to the engine 4.

  The generator 8 generates electric power in response to the rotation of the engine 4. If the system power supply 16 is, for example, AC 100 [V], the power generation output is similarly AC 100 [V]. This power generation output is supplied to the load 18 through the control means 14 at the time of a power failure of the system power supply 16. The load 18 receives power generation output and consumes power. The detection means 10 detects the power consumption of the load 18 and provides this detection output to the control means 14.

  The information table 12 stores at least an air-fuel mixture amount and a mixture ratio λ corresponding to the power consumption of the load 18 for each target rotational speed Nf of the engine 4. In the control of the engine 4, the amount of air-fuel mixture is determined mainly at the throttle position, and the mixture ratio λ is the ratio of the fuel gas G and air Ar, and is determined mainly at the position of the needle. When the position of the needle is changed, the amount of air-fuel mixture changes accordingly, but if the fluctuation value is ignored, the position of the needle = mixing ratio λ. The information table 12 may store, for example, the position of the throttle, the position of the needle, and the set mixture ratio λ as the air-fuel mixture amount and the mixture ratio λ.

  The control means 14 drives the engine 4 by setting the air-fuel mixture amount and the mixture ratio λ required for the target rotational speed Nf of the engine 4 in the air-fuel mixture adjusting means 6. After the driving, the control unit 14 refers to the information table 12 and updates the mixture amount and mixture ratio set in the mixture adjustment unit 6 to the mixture amount and mixture ratio λ corresponding to the power consumption of the load 18. Then, the engine 4 is controlled to the target rotational speed Nf.

  In the gas engine generator 2, a target rotational speed Nf corresponding to the frequency f of the system power supply 16 is set. Assuming that the electrical angle of the generator 8 is rotated twice by one rotation of the mechanical angle of the engine 4, when f = 50 [Hz]: Nf1 = 50 × 60 ÷ 2 = 1500 [rpm], 60 [Hz] In the case of: Nf2 = 60 × 60 ÷ 2 = 1800 [rpm].

<Processing procedure>

  FIG. 2 shows a processing procedure for engine control of the gas engine generator. This processing procedure is an example of the control method or control program for the gas engine generator of the present invention.

  This processing procedure includes creation of the information table 12 (S101), driving of the engine 4 (S102), detection of power consumption of the load 18 (S103), adjustment of the air-fuel mixture amount and the mixture ratio λ (S104). In creating the information table 12, the information table 12 including at least the air-fuel mixture amount and the mixture ratio λ corresponding to the power consumption is created in advance for each target rotational speed Nf1 and Nf2 of the engine 4.

  The control means 14 sets the amount of air-fuel mixture at no load and starts driving the engine 4 (S102).

  After driving the engine 4, the power consumption of the load 18 is acquired (S103). This power consumption is detected by the detection means 10, and for example, the applied voltage and load current of the load 18 may be detected.

  After the engine is driven, the mixture amount and the mixture ratio λ set in the mixture adjustment means 6 are updated to the mixture amount and the mixture ratio λ corresponding to the power consumption of the load 18 by referring to the information table 12. (S104).

<Effect of one embodiment>

  (1) Since the increase / decrease in the power consumption of the load 18 is detected and the mixture amount and the mixture ratio of the mixture set in the mixture adjustment means 6 are read from the information table 12 and updated, fluctuations in the power consumption of the load 18 In addition, the responsiveness of engine control is improved.

  (2) Since the generated power is controlled in response to fluctuations in the power consumption of the load 18, a stable generated output can be supplied to the load 18.

  (3) Since the amount of air-fuel mixture set in the air-fuel mixture adjusting means 6 and the mixture ratio λ of the air-fuel mixture are adjusted in accordance with fluctuations in the power consumption of the load 18, an exhaust sensor or a mixture for controlling the air-fuel ratio λ The ratio detection means can be eliminated.

(4) The AC power supply output control can be realized by the gas engine generator 2, and it is not necessary to install an inverter control device in the gas engine generator 2.

<Gas engine generator 2>

  FIG. 3 shows an embodiment of the gas engine generator 2. The configuration shown in the figure is an example, and the present invention is not limited to such configuration. In FIG. 3, the same reference numerals are given to the portions common to FIG.

  The gas engine generator 2 includes a casing 20, and the casing 20 includes an engine 4, a generator 8, a battery 21, a control box 22, an intake section 24, an exhaust section 26, and the like.

  The engine 4 includes a mixer 28, a starter 30, an ignition unit 32, and a coolant unit 34. The starter 30 is a motor that generates a powerful torque that overcomes the rotational resistance generated in the compression process of the engine 4. The starter 30 rotates using the battery 21 as a power source, and the rotation speed is, for example, 50 to 300 [rpm].

  The ignition unit 32 includes a plurality of spark plugs 36-1, 36-2, 36-3, and an igniter 38 is provided in each of the spark plugs 36-1, 36-2, 36-3. -2 and 40-3.

  The engine 4 is, for example, a water-cooled engine. Accordingly, the coolant unit 34 cools the engine 4 by circulating cooling water. A water pump 42 and a radiator 44 are used for the coolant portion 34. The water pump 42 is used for circulating the cooling water, and rotates by receiving the rotational force of the engine 4. The radiator 44 exchanges heat between the surrounding air and the circulating cooling water by the rotation of the radiator fan 46 to dissipate the cooling water. The coolant temperature is detected by the temperature sensor 48-1. The engine 4 is provided with a speed sensor 48-2 for detecting the rotational speed of the engine 4, a cam position sensor 48-3 for detecting the position of the cam, and a hydraulic switch 48-4 that is turned on / off by hydraulic pressure. The exhaust from the engine 4 is exhausted through a muffler 76 in the exhaust unit 26.

  The mixer 28 is an example of the air-fuel mixture adjusting means 6. The mixer 28 is supplied with air Ar from the intake section 24 and fuel gas G from the fuel supply section 50. The supply path 52 for the fuel gas G is provided with electromagnetic valves 54-1 and 54-2 and a gas regulator 56. The electromagnetic valves 54-1 and 54-2 are used to supply and stop the fuel gas G. The gas regulator 56 is a pressure regulator (zero governor) that adjusts the pressure of the supplied fuel gas G to the same pressure as the atmospheric pressure, and the fuel gas does not act between the gas regulator 56 and the engine 4 unless intake negative pressure acts. The supply of G is blocked, and the supply of the fuel gas G to the mixer 28 is stabilized. The mixer 28 is driven by a mixer driving unit 58, and a control signal is given to the mixer driving unit 58 from the control box 22.

  The generator 8 receives the rotation of the engine 4 to generate power, and is, for example, an inverterless generator. The generator 8 is provided with an automatic voltage regulator (AVR) 60. The AVR 60 adjusts the power generation output to a constant voltage without being affected by the load fluctuation or the rotation speed.

  The control box 22 includes an electric control unit (ECU) 62, an automatic transfer switch (ATS) 64, an operation panel 66, and the like. The ECU 62 controls power transmission / reception, engine control, power supply switching, battery charging, and the like. The power generation output of the generator 8 is input to the ECU 62 and supplies power to the battery 21.

  In this example, a commercial power supply 68 is used as the system power supply 16. The commercial power supply 68 is fed to the ECU 62 via the surge box 70 and the ATS 64. The surge box 70 absorbs the surge of the system power supply 16. A load 18 is connected to the ATS 64 via an electromagnetic contactor 72 and a leakage breaker 74. The ATS 64 detects a power failure of the commercial power source 68, and selects the commercial power source 68 at the time of grid connection, and switches to the power generation output of the generator 8 at the time of power failure.

<Control system of gas engine generator 2>

  FIG. 4 shows an example of a control system of the gas engine generator 2.

  The control system includes a generator 8, a load 18, functional units in the control box 22, electromagnetic valves 54-1 and 54-2, and an engine assembly (ASSY) 78. In the engine ASSY 78, the sensors on the engine 4 side and the mixer drive unit 58 of the mixer 28 are configured as one unit separate from the engine 4. In this example, a temperature sensor 48-1, a speed sensor 48-2, a cam position sensor 48-3, a hydraulic switch 48-4, an igniter 38, an igniter control unit 80, a throttle motor 82 and a needle motor 84 are included. The igniter control unit 80 outputs an ignition signal to the igniter 38 in accordance with the cam position detected by the cam position sensor 48-3.

  The ECU 62 is configured by a computer. The ECU 62 includes a processor 86, an EEPROM (Electrically Erasable Programmable Read-Only Memory) 88, a RAM (Random-Access Memory) 90, an input / output unit (I / O) 92, a current measurement circuit 94, and a voltage measurement circuit 96. The processor 86 executes a program stored in the storage means and manages various controls of the gas engine generator 2 including control of the mixer 28 based on information stored in the information table 12 in the EEPROM 88. A ROM (Read-Only Memory) may be used for storing the program, but an EEPROM 88 may be used. A recording medium such as a hard disk or a semiconductor memory may be used for the ROM.

  The information table 12 stored in the EEPROM 88 records the throttle position, needle position, efficiency, etc. corresponding to the engine speed. The RAM 90 expands a program and is used as an engine control work area.

  The I / O 92 is used for inputting measurement outputs of the current measuring circuit 94 and the voltage measuring circuit 96, input / output of the functional part of the operation panel 66, input / output of the engine ASSY 78, and output to the electromagnetic valves 54-1 and 54-2. .

  The current measurement circuit 94 and the voltage measurement circuit 96 are examples of the detection unit 10. The current measuring circuit 94 detects the load current using current transformers 94-1 and 94-2 provided in a power supply line 98 that supplies the power generation output of the generator 8 to the load 18. In this example, a current transformer 94-1 is provided in the R phase of the feeder line 98, and a current transformer 94-2 is provided in the T phase. The voltage measurement circuit 96 receives the power generation output of the generator 8 and detects the applied voltage of the load 18. These detection outputs are taken into the I / O 92, and the current and voltage are used as load information. The processor 86 calculates the power consumption consumed by the load 18 and searches for the throttle position and needle position.

  The operation panel 66 includes a display unit 100, an operation switch 102, and an emergency stop switch 104. For example, an LCD (Liquid Crystal Display) is used for the display unit 100 to display a control status, input information, and the like. The operation switch 102 is used to start operation. When the operation switch 102 is turned on, the operation of the ECU 62 is started. The emergency stop switch 104 is operated during an emergency stop.

  FIG. 5 shows an example of the mixer 28 and the mixer driving unit 58. In this example, the mixer 28 is provided with an intake passage 106. A throttle valve 108 that takes in air Ar and changes the amount of air is rotatably attached to the intake passage 106 by a rotation mechanism 110. A throttle motor 82 of the mixer driving unit 58 is connected to the rotating mechanism 110. By the rotation of the throttle motor 82, the opening degree of the throttle valve 108 is adjusted. That is, this is the throttle position described above.

  A fuel supply passage 112 is formed on the intake side of the intake passage 106 from the throttle valve 108. A needle 114 is attached to the middle of the fuel supply path 112 by an advance / retreat mechanism 116 so that the needle 114 can advance / retreat. A needle motor 84 of the mixer drive unit 58 is connected to the advance / retreat mechanism 116. By the rotation of the needle motor 84, the position of the needle 114 is adjusted, and the opening degree of the ejection port portion 118 through which the fuel gas G is ejected is adjusted. That is, this is the needle position described above.

  According to such a configuration, the amount of air Ar is adjusted by the throttle valve 108, and the amount of fuel gas G is adjusted by the position of the needle 114, so the supply amount of the air-fuel mixture M to the engine 4 and the mixture ratio λ are adjusted. be able to.

<Rotation control of engine 4>

  FIG. 6 shows functional blocks for controlling the rotational speed of the engine 4.

In this rotational speed control, as control for controlling the rotational speed N of the engine 4 to the target rotational speed Nf corresponding to the set frequency f:
A) Feedforward (FF) control that gives throttle position and needle position at no load b) Power consumption of load 18, FF control that updates throttle position and needle position according to the power consumption c) Actual rotation speed The feedback (FeedBack: FB) control for the rotation speed correction is included.

  6, G (s) is a transfer function of the engine 4 having the throttle position and the needle position as input elements, FF is an element of FF control, Ts is a time constant, K is a coefficient, 120-1, 120-2, 120 -3 and 120-4 are adders. In the FF, an FF value representing a no-load throttle position and a needle position is set. Thereby, the FF control of a) is performed.

  In order to perform the FF control of (a) above, a disturbance observer 122 is used in this control system. The disturbance observer 122 uses the fluctuation of the power consumption of the load 18, the adjustment value of the mixing ratio λ, and the frequency f1 or f2 as input elements, and outputs the throttle position and needle position as disturbance control output. The disturbance observer 122 is information processing means realized by a computer such as the processor 86 described above. As the disturbance observer 122, the mixture ratio tables 124-1 and 124-2, which are examples of the information table 12 described above, are used. The frequency f1 is, for example, 50 [Hz] of the system frequency, and the frequency f2 is, for example, 60 [Hz] of the system frequency. Therefore, the mixing ratio table 124-1 corresponds to the frequency f1 (target rotation speed Nf = 1500 [rpm]), and the mixing ratio table 124-2 corresponds to the frequency f2 (target rotation speed Nf = 1800 [rpm]). The adjustment value of the mixing ratio λ is an adjustment due to changes in atmospheric pressure due to altitude, variations in air temperature, and various parts such as needles, and is increased or decreased at a set ratio (−99 to + 99%) with respect to the needle value.

  In order to perform the FB control of c), the rotational speed N of the engine 4 is detected by the speed sensor 48-2, and this detected value is fed back to the adder 120-1. Thereby, P control, I control, and D control are performed. The feedback rotation speed N is subtracted from the target rotation speed Nf by the adder 120-1, and the throttle position is controlled by the deviation value of both. This control is executed in the system from the adder 120-1 to the adder 120-4.

  In the gas engine generator 2 that performs such control, the frequency f of the power generation output is determined by the frequency of the system power supply 16, and this frequency f depends on the rotational speed N of the engine 4. A target rotational speed Nf is determined according to the frequency f, and the rotational speed N of the engine 4 is controlled to this target rotational speed Nf. This rotational speed N is controlled by the throttle position and needle position of the mixer 28. The throttle position represents the air-fuel mixture amount, and the needle position represents the fuel concentration.

  In the generator 2 using the engine 4 as a drive source, adjustment of the throttle position and the needle position is necessary to maintain the engine speed N at the target engine speed Nf even if the power consumption of the load 18 fluctuates. .

  There are the following factors in the fluctuation factors affecting the rotational speed control.

a. The rotational speed N of the engine 4 varies depending on the throttle opening. That is, if the throttle valve 108 is opened, the rotational speed increases, and if the throttle is closed, the rotational speed decreases. Since the rotation speed is the number of rotations per unit time, the increase / decrease in the rotation speed is an increase / decrease in the number of rotations.
b. The needle position also affects the rotational speed.
c. When the power consumption of the load 18 increases, the rotational speed N of the engine 4 decreases.
d. The rotational speed N of the load 18 and the engine 4 depends on the throttle position and the needle position, and these positions are generally determined.
e. The power consumption of the load 18 can be detected electrically.
f. The disturbance elements other than the load 18 include a detection error of a sensor that detects power consumption of the load 18, a speed acquisition error of the speed sensor (for example, a clock error of the ECU 62), a characteristic variation of the engine 4, a characteristic variation of the generator 8, The gas pressure of the fuel gas G, the atmospheric pressure fluctuation due to the altitude, the ambient temperature of the engine 4 and the like are assumed.

  Therefore, in this engine control, the following control is performed.

  (1) Since the fluctuation of the power consumption of the load 18 appears in the change of the rotational speed N of the engine 4, the throttle position (opening) is adjusted according to the change of the rotational speed N. This is performed by FB control.

(2) The power consumption of the load 18 and its fluctuations are regarded as disturbances. This power consumption is directly detected to configure disturbance robust control. Specifically, the disturbance robust control is as follows.
(2-1) d. The no-load throttle position is given as an FF value.
(2-2) d. And the throttle position and needle position are given by the mixing ratio table 124-1 or the mixing ratio table 124-2 according to the power consumption of the load 18.

  (3) Disturbance elements other than the load 18 are set to the I component of PID (Proportional-Integral-Derivative) control between the adders 120-1 and 120-2. This ensures robustness.

  (4) Since the power consumption of the load 18 is the product of the load current and the applied voltage, fluctuations in the rotational speed N can be detected earlier than the direct detection of the rotational speed N by measuring these individually.

  (5) The gas engine generator 2 having good responsiveness to fluctuations in the power consumption of the load 18 can be obtained.

<Mixing ratio tables 124-1, 124-2>

  In this gas engine generator 2, two types of mixing ratio tables 124-1, 124-2 are used as an example. The mixing ratio table 124-1 is used when the power generation output frequency f = 50 [Hz] (the target engine speed Nf = 1500 [rpm]), and the mixing ratio table 124-2 is the power generation output frequency. It is used when f = 60 [Hz] (target rotational speed Nf = 1800 [rpm] of the engine 4).

  As shown in A of FIG. 7, the mixing ratio table 124-1 stores the throttle position and needle position corresponding to the power consumption [kW] of the load 18. The mixing ratio table 124-2 also stores the throttle position and needle position corresponding to the power consumption [kW] of the load 18 as shown in FIG. 7B. These mixing ratio tables 124-1 and 124-2 are stored in the EEPROM 88 (FIG. 4), the FLASH memory (not shown) built in the processor 86, or the like.

  Each value of the mixing ratio table 124-1 is obtained from the measured mixing ratio table 126-1 (A in FIG. 8), and each value of the mixing ratio table 124-2 is obtained from the measured mixing ratio table 126-2 (A in FIG. 9). ing. The throttle positions in the mixture ratio tables 124-1 and 124-2 are obtained by subtracting the throttle position value when the power consumption of the load 18 is 0 from the throttle positions in the actually measured mixture ratio tables 126-1 and 126-2. is there.

<Processing of disturbance observer 122>

  The disturbance observer 122 using the mixing ratio tables 124-1 and 124-2 performs the following processing.

  If the frequency f of the power generation output is f = 50 [Hz], the mixing ratio table 124-1 with the target rotational speed Nf = 1500 [rpm] is selected. If the frequency f of the power generation output is f = 60 [Hz], the mixture ratio table 124-2 with the target rotational speed Nf = 1800 [rpm] is selected.

  In this example, the target rotation speed Nf = 1500 [rpm], 1800 [rpm] is exemplified, but if it is other than this, the frequency setting may be followed.

  The power consumption of the load 18 is observed, and for example, the needle position and the throttle position are retrieved from the mixture ratio table 124-1. The needle position is adjusted by adding the number of mixture ratio adjustments to the needle position obtained by this search. Regarding the power consumption value of the load 18, the intermediate value of each value may be calculated by linear interpolation from the preceding and succeeding values.

  The throttle position is automatically adjusted by PID control. If such an adjustment form is taken, a moderate and favorable responsiveness can be obtained. That is, the PID control output is used for dispersion absorption, and PID control output = 0 is desirable. In this case, emphasis is placed on the FF value and disturbance robust control, the P control is small, and the I control may be weak.

<Mixing Ratio Tables 124-1, 124-2 Creation Processing>

  Each value of the mixing ratio tables 124-1 and 124-2 starts the gas engine generator 2, and from the actual measurement values, the actual mixing ratio tables 126-1 (A in FIG. 8) and 126-2 (A in FIG. 9). Create and ask.

  FIG. 8A shows the actually measured mixing ratio table 126-1 when f = 50 [Hz] and Nf = 1500 [rpm].

  This actually measured mixture ratio table 126-1 is created by starting the engine 4 and changing the power consumption value of the load 18 to obtain the throttle position, needle position and mixture ratio λ at which the efficiency η is the best value.

  When these values are graphed, as shown in FIG. 8B, in order to obtain uniform efficiency with respect to the output [kW], it is understood that the values are not linear changes but irregular values. . Therefore, a throttle position and a needle position at which the efficiency η is good within a range where the engine speed does not become unstable are obtained from these actually measured values, and a mixing ratio table 124-1 shown in A of FIG. 7 is created.

  FIG. 9A shows the actually measured mixing ratio table 126-2 when f = 60 [Hz] and Nf = 1800 [rpm].

  Similarly, the actually measured mixture ratio table 126-2 is created by starting the engine 4, changing the power consumption value of the load 18, and obtaining the throttle position, needle position, and mixture ratio λ at which the efficiency η is the best. .

  When these values are graphed, as shown in FIG. 9B, in order to obtain a uniform efficiency with respect to the output [kW], it is not a linear change but an irregular value. This is the same as B in FIG. However, as is clear from a comparison between B in FIG. 9 and B in FIG. 8, the value of the mixing ratio λ is completely different when the target rotational speed Nf is different. Therefore, a throttle position and a needle position at which the efficiency η is good within a range where the engine speed does not become unstable are obtained from these actually measured values, and a mixing ratio table 124-2 shown in FIG. 7B is created.

  In the actually measured mixture ratio tables 126-1 and 126-2, comparing the values in the column of load = 0, it can be seen that the target rotational speed Nf and the throttle position are not in a proportional relationship. If the target rotational speed Nf is high, the negative pressure of the engine 4 increases, and even if the throttle is throttled, the amount of air increases, and the relationship between the throttle position and the rotational speed does not become linear.

<Engine control procedure>

  FIG. 10 shows a processing procedure for engine control. This processing procedure is an example of the control program for the gas engine generator of the present invention and the control method thereof.

  In this processing procedure, the throttle position and the needle position at the time of no load are set to the FF value, and the engine 4 is started (S201).

  After the engine 4 is started, the power consumption of the load 18 is detected (S202). The power consumption can be detected by measuring the applied voltage and load current of the load 18 and calculating.

  After detecting the power consumption, the value is used to refer to the mixture ratio table 124-1 (or the mixture ratio table 124-2) to obtain the throttle position and needle position corresponding to the power consumption of the load 18 (S203). ).

  The throttle position and needle position of the mixer 28 are updated to the throttle position and needle position acquired from the mixing ratio table 124-1 (or the mixing ratio table 124-2) (S204).

  Then, the rotational speed N of the engine 4 is detected (S205), and the rotational speed N is corrected using the rotational speed N and the target rotational speed Nf (S206). Similarly, the processes of S202 to S206 are continuously executed as long as the rotation of the engine 4 is maintained. Thereby, the rotation speed N can be controlled to the target rotation speed Nf.

<Effect of Example>

  According to the above example, in addition to the effect of the above embodiment, the following effect can be obtained.

  (1) The throttle position and needle position at the time of no load at which the target rotational speed Nf can be obtained are set in the mixer 28, and the engine is started at the target rotational speed Nf, so that the engine rotational speed can quickly reach the target rotational speed. . In this case, what is necessary is just to refer the mixing ratio table 124-1 or the mixing ratio table 124-2 for the throttle position and the needle position when there is no load.

  (2) The set value of the mixer 28 is updated to the throttle position and the needle position obtained from the mixing ratio table 124-1 or the mixing ratio table 124-2 in response to an increase or decrease in the power consumption of the load 18. Rapid engine rotation control can be performed.

  (3) The output of the generator 8 can be made to follow the increase and decrease of the power consumption of the load 18 to absorb the increase and decrease change on the load 18 side, and a stable generation output can be provided to the load 18.

  (4) The throttle position and needle position values can be set to the most efficient values in advance, and efficient engine control and rotation control can be performed.

  (5) It is possible to cope with various system frequencies and to realize engine control with high controllability.

  (6) If there is no value corresponding to the power consumption in the mixing ratio table 124-1 or the mixing ratio table 124-2, the two closest values across the values close to the power consumption are selected, and from these values If the complement calculation is performed, the shortage of the mixture ratio table 124-1 or the mixture ratio table 124-2 can be quickly replenished, and stable engine control can be realized.

[Other Embodiments]

a. Although the gas engine generator has been exemplified in the above embodiment, the engine rotation can be controlled by using the generator for controlling the gas engine, and the present invention is not limited to the above embodiment. .
b. In the above embodiment, the power consumption is detected by measuring the voltage and current, but the power consumption may be obtained using only the load current.

As described above, the most preferable embodiment of the present invention has been described. The present invention is not limited to the above description. Various modifications and changes can be made by those skilled in the art based on the gist of the invention described in the claims or disclosed in the specification. It goes without saying that such modifications and changes are included in the scope of the present invention.

The present invention can efficiently perform engine control of a gas engine generator using fuel gas, uses power consumption of a load, and shows an information table for throttle position and needle position of an air-fuel mixture mixer corresponding to this power consumption. It is useful because it can realize quick response.

DESCRIPTION OF SYMBOLS 2 Gas engine generator 4 Engine 6 Mixture adjustment means 8 Generator 10 Detection means 12 Information table 14 Control means 16 System power supply 18 Load 20 Case 21 Battery 22 Control box 24 Intake part 26 Exhaust part 28 Mixer 30 Starter 32 Ignition part 34 Coolant 36-1, 36-2, 36-3 Spark plug 38 Igniter 40-1, 40-2, 40-3 Ignition coil 42 Water pump 44 Radiator 46 Radiator fan 48-1 Temperature sensor 48-2 Speed sensor 48 -3 Cam position sensor 48-4 Hydraulic switch 50 Fuel supply part 52 Supply path 54-1 and 54-2 Solenoid valve 56 Gas regulator 58 Mixer drive part 60 AVR
62 ECU
64 ATS
66 Operation Panel 68 Commercial Power Supply 70 Surge Box 72 Magnetic Contactor 74 Earth Leakage Breaker 76 Muffler 78 Engine ASSY
80 igniter control unit 82 throttle motor 84 needle motor 86 processor 88 EEPROM
90 RAM
92 I / O
94 Current measurement circuit 94-1, 94-2 Current transformer 96 Voltage measurement circuit 98 Power supply line 100 Display unit 102 Operation switch 104 Emergency stop switch 106 Intake path 108 Throttle valve 110 Rotation mechanism 112 Fuel supply path 114 Needle 116 Advance / retreat mechanism 118 Injection Outlet portion 120-1, 120-2, 120-3, 120-4 Adder 122 Disturbance observer 124-1, 124-2 Mixing ratio table 126-1, 126-2 Actual mixing ratio table

Claims (6)

A gas engine generator controlled by an engine speed corresponding to a predetermined frequency,
An air-fuel mixture adjusting means for generating an air-fuel mixture containing fuel gas and adjusting the mixture ratio of the fuel gas in the air-fuel mixture and the amount of air-fuel mixture supplied to the engine;
Detection means for detecting the power consumption of the load receiving the power generation output;
An information table storing at least the mixture amount and the mixture ratio corresponding to the power consumption for each target rotational speed;
The air-fuel mixture amount and the mixture ratio required for the target rotational speed are set in the air-fuel mixture adjusting means, the engine is driven, and the air-fuel mixture amount and the mixture ratio corresponding to the power consumption are updated with reference to the information table Control means for controlling the engine to the target rotational speed;
A gas engine generator comprising:   The control means drives the engine according to the air-fuel mixture amount and the mixture ratio required for the target rotational speed at startup and no load, and is detected by the detection means from the information table after the engine is started. The amount of air-fuel mixture and the mixture ratio corresponding to the power consumption are obtained, or the amount of air-fuel mixture and the air-fuel ratio that are complementary to the amount of air-fuel mixture and the air-fuel ratio are obtained. The gas engine generator according to claim 1, wherein the mixing ratio is updated.   The information table includes an efficiency obtained by the mixture amount and the mixture ratio, and the control unit selects the mixture amount and the mixture ratio according to the efficiency. Gas engine generator. A control program for causing a computer mounted on a gas engine generator to be controlled at an engine speed corresponding to a predetermined frequency,
Receives power consumption information detected from the load that receives power generation output,
At least the mixture amount and the mixture ratio set in the mixture adjustment means for generating the mixture containing fuel gas and adjusting the mixture ratio of the fuel gas in the mixture, and adjusting the amount of mixture supplied to the engine Store it in the information table corresponding to the power consumption,
The air-fuel mixture amount and the mixture ratio required for the target rotational speed are set in the air-fuel mixture adjusting means, the engine is driven, and the air-fuel mixture amount and the mixture ratio corresponding to the power consumption are updated with reference to the information table And a control program for a gas engine generator for realizing the function of controlling the engine at the target rotational speed by the computer. A recording medium used for execution of a control program to be executed by a computer mounted on a gas engine generator controlled at an engine speed corresponding to a system power supply frequency,
Loads at least the mixture amount and the mixture ratio that are set in a mixture adjustment means that generates a mixture containing fuel gas and adjusts the mixture ratio of the fuel gas in the mixture and the amount of mixture supplied to the engine A recording medium in which an information table to be stored in correspondence with the power consumption of the recording is recorded. A control method of a gas engine generator controlled to an engine speed corresponding to a predetermined frequency,
Loads at least the mixture amount and the mixture ratio that are set in a mixture adjustment means that generates a mixture containing fuel gas and adjusts the mixture ratio of the fuel gas in the mixture and the amount of mixture supplied to the engine Creating an information table to be stored corresponding to the power consumption of
Detecting the power consumption of the load receiving the power generation output;
The air-fuel mixture amount and the mixture ratio required for the target rotational speed are set in the air-fuel mixture adjusting means, the engine is driven, and the air-fuel mixture amount and the mixture ratio corresponding to the power consumption are updated with reference to the information table And controlling the engine to the target rotational speed;
A control method for a gas engine generator, comprising:

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