JPH06307260A - Gas turbine controller - Google Patents

Abstract

PURPOSE:To stabilize control in switching of two stage combustion operation so as to carry out stable control. CONSTITUTION:A fuel controlling valve 9 for setting a total gas fuel supply amount is arranged in the upstream side position beyond a branch point of a fuel supply pipe, the primary side and the secondary side fuel distributing valves 10, 11, which set s distribution ratio of a supply fuel, are arranged in the primary side and the secondary side fuel supply pipes individually, a function generator 21, which sets a distribution ratio to the secondary side fuel distribution valve 11 on the basis of a position signal of the fuel controlling valve 9, is provided, and the function generator 21 varies the distribution ratio sharply at a switching point of fuel distribution and is set to make its hysteresial action in the rise/fall of the position signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine controller for controlling NOx reduction of a gas turbine applied to a power plant or the like by two-stage combustion.

[0002]

2. Description of the Related Art Conventionally, liquid fuels such as light oil and kerosene have been frequently used as gas turbine fuels, but in recent years, from the viewpoint of diversifying utilization of energy resources, vaporized liquefied natural gas (LNG) and liquefied propane gas ( There is a tendency that the operation by the gas fuel that is operated by burning LPG) is increased. It is expected that the number of such fuel-fired gas turbines will further increase in the future, reflecting the progress of gas transportation technology and the measures of energy consumption plans to balance various energy ratios by increasing the gas fuel ratio. .

On the other hand, with respect to gas turbines, not only efficient operation but also social demands such as pollution control and environmental control are increasing, and it is particularly urgent to suppress nitrogen oxides (NOx). It is known that the generation of NOx is caused by an increase in the combustion temperature, including local combustion in the gas turbine combustor. Until now, water injection or steam injection was performed in the combustor, NO by reducing the effective combustion temperature
Means to achieve x-ization are adopted.

However, when a method such as water injection or steam injection is used, the combustion temperature as an average temperature in the combustor decreases, so that the combustion efficiency deteriorates and the thermal efficiency of the gas turbine decreases. is there.

Therefore, in recent years, instead of water injection or steam injection, NOx reduction can be achieved while maintaining the thermal efficiency of the gas turbine.
The technology based on the staged combustion method is drawing attention. This two-stage combustion method blows gas fuel not only from the inlet of the combustor but also from the wake side of the combustor to make the fuel distribution uniform in the combustor and prevent local high temperatures. It realizes NOx conversion, and can maintain a high temperature in the entire combustor as uniformly as possible without lowering the combustion temperature unlike water injection or steam injection.

FIG. 7 shows a conventional example of a gas turbine control device in a gas turbine power generation system to which such a two-stage combustion system is applied. In this gas turbine control device, a compressor 1, a gas turbine 2 and a generator 3 are coaxially arranged, and the fuel injected in the combustor 4 is compressed by the compressor 1.
The gas turbine 2 is rotatively driven by the combustion gas combusted by the compressed air.

In the above control device, one fuel supply pipe 5 guided from a gas fuel supply source (not shown) is branched into two, and one of the branch pipes serves as a primary side fuel supply pipe 6 and is the uppermost stream of the combustor 4. And the other side of the branch pipe is connected as a secondary side fuel supply pipe 7 to the downstream side of the most upstream side of the combustor 4.

A fuel stop valve 8 and a fuel control valve 9 for controlling the total gas fuel supply amount are provided at positions upstream of the branch points of the fuel supply pipes 6 and 7. Then, in the primary side fuel supply pipe 6 and the secondary side fuel supply pipe 7,
A primary fuel distribution valve 10 and a secondary fuel distribution valve 11 that set the distribution ratio of the supplied fuel are respectively provided.

When operating the turbine, first, the gas turbine 2
Is started to rotate by a starter (not shown) such as a motor arranged coaxially therewith, and when the air purging in the gas turbine 2 by the compressor 1 is completed, the fuel stop valve 8, fuel control The valve 9 and the primary fuel distribution valve 10 are opened, and the gas fuel is supplied to the most upstream part of the combustor 4 and ignited.

After this ignition, the gas turbine 2 is speeded up after a certain period of warm-up operation, and after reaching the rated rotation speed, the operation is performed in parallel with the power system, and the load is increased to reach the rated load. During this time, the flow rate of the gas fuel flowing into the combustor 4 of the gas turbine 2 is controlled by the fuel control valve 9. That is,
The fuel control valve 9 controls the fuel flow rate required for speed control and load control of the gas turbine 2.

The range of flow rate control required for each operation of the gas turbine 2 is extremely wide, and the opening of the fuel control valve 9 is extremely low in a low rotational speed and low flow rate range such as during ignition and warm-up operation. It is so small that control instability tends to occur. Therefore, in order to avoid this control instability, the fuel stop valve 8 is provided with a control function such that its downstream side fuel pressure is proportional to the turbine speed, whereby the fuel control valve 9 operates at a low turbine speed. By keeping the pressure on the upstream side low, the operation is performed such that the opening degree of the fuel control valve 9 is set sufficiently large,
It is designed to avoid control instability.

During the ignition and warm-up operation of the gas turbine 2, the valve opening of the fuel control valve 9 is controlled by a constant value signal, and when the speed is increased or the load is increased thereafter, the fuel flow rate required for speed / load control is controlled. Is controlled by a command signal from the gas turbine controller 12. The fuel control valve 9 is set with a minimum opening signal of a certain value or more from a low value priority circuit (not shown) so as not to blow out in the combustor 4 in any operating state such as ignition. It

Here, the fuel injection to the load of the gas turbine 2 will be described with reference to FIGS. 8 (A) to 8 (C).

The gas turbine 2 is operated only by fuel supply from the primary side fuel supply pipe 6 until ignition, rated speed, no load and intermediate load. That is, the secondary fuel distribution valve 11 is fully closed.

As the load on the gas turbine 2 increases, FIG.
As shown in (C), since the NOx concentration also increases in proportion, the primary side fuel distribution valve 10 is narrowed down at the switching point P1 of the gas turbine intermediate load, and the secondary side fuel distribution valve 1
1 is opened, and the primary side fuel flow rate ratio R as shown in FIG.
1 (1-m) is reduced and the secondary fuel flow rate ratio R2 (m) is increased, whereby the primary fuel flow rate N1 is reduced and the secondary fuel flow rate R2 (m) is reduced as shown in FIG. 8 (A). Flow rate N
Increase by 2.

By this operation, the two-stage combustion in the combustor 4 is achieved, and the NOx concentration can be rapidly reduced as shown in FIG. 8 (C). This switching point P1 is the combustor 4
Of the intermediate load of the gas turbine 2 according to the amount of NOx generated. The two-stage combustion mode is achieved by controlling the fuel flow rate ratio at each of the fuel distribution valves 10 and 11.

The distribution ratio m to the secondary side fuel distribution valve 11 for suppressing the NOx generation amount to the maximum is as shown in FIG. 9 based on the operation data and test data so far. It is known that the combustion temperature T is uniquely determined. However, in reality, there is no sensor capable of measuring the combustion temperature T of the gas turbine 2 which reaches a thousand and several hundred degrees. Therefore, in order to know the accurate combustion temperature T, the exhaust gas temperature of the gas turbine 2, the compressor outlet pressure, etc. Need to be calculated from

It has been found that the combustion temperature T is substantially proportional to the output P of the gas turbine 2. Further, since the output P of the gas turbine 2 is proportional to the valve position control signal n to the fuel control valve 9, it can be seen that the combustion temperature T is eventually proportional to the valve position control signal n. Using this relationship, the distribution ratio m to the secondary fuel distribution valve 11 is defined as a function of the valve position control signal n to the fuel control valve 9.

FIG. 10 shows Japanese Patent Application No. 3-211 of the present applicant.
1 shows the control circuit of the fuel control valve 9, the primary side and secondary side fuel distribution valves 10 and 11 as shown in the specification No. 166.

In FIG. 10, the gas turbine controller A
Is a valve position control means A1 for outputting a valve position control signal n for speed / load control of the gas turbine 2 to the fuel control valve 9 to set an opening for supplying total gas fuel, and from this valve position control means A1. Distribution ratio control means for outputting a distribution ratio setting signal to the primary side and secondary side fuel distribution valves 10 and 11 and setting the respective valve opening degrees based on the low NOx related data corresponding to the output valve position control signal n. It consists of A2.

Further, the gas turbine controller A has a function generator 12 and a calculator 13. A fuel control valve valve position control signal (hereinafter, simply referred to as valve position control signal) n of the fuel control valve 9 for controlling the speed / load of the gas turbine 2 is input to the control device 12, and the fuel control valve 9 is It is adapted to be controlled by the valve position control signal n.

Further, the valve position control signal n is the function generator 1
Entered in 2. Since the valve position control signal n has a proportional or linear relationship to the load of the gas turbine 2 as described above (see FIG. 9), the fuel distribution ratio is calculated from the valve position control signal n based on the relationship data obtained in advance. It is determined.

A signal of the distribution ratio m is output from the function generator 12 to the secondary side fuel distribution valve 11, and a distribution ratio of 1-m is calculated by the calculator 13 to the primary side fuel distribution valve 10. A signal having a distribution ratio of 1-m is output from the calculator 13.

Therefore, the gas turbine 2 is controlled by the valve position control signal n to the fuel control valve 9 until the load control is performed through the ignition in the combustor 4, the speed control of the gas turbine 2 and the inclusion thereof.

From the function generator 12 to the secondary side fuel distribution valve 11 based on the valve position control signal n, "0" is output from the time when the load of the gas turbine 2 starts to increase until it reaches the intermediate load. Therefore, the primary side fuel distribution valve 10 is fully opened and the secondary side fuel distribution valve 11 is fully closed.

When the preset valve position control signal value is reached, the secondary side fuel distribution valve 11 is controlled by the output signal from the function generator 12, and the two-stage combustion is performed. Low NOx operation is realized by this two-stage combustion.

[0027]

However, the above-mentioned prior art has the following problems. That is,
Particularly, the fuel switching operation is started at the switching start set point n1 shown in FIG. 10 corresponding to the switching point P1 in FIG.

When this switching operation is started, the control circuit A shown in FIG. 10 starts the closing operation of the primary fuel distribution valve 10 and the opening of the secondary fuel distribution valve 11, and the combustor 4 is started. Although the fuel is injected to the downstream side of the fuel injection system, immediately after the injection is started, as shown in FIG. 10, since only a small amount of fuel is injected, the fuel injected from the secondary side easily causes incomplete combustion. During this time, since the total fuel flow rate remains constant, the load drops due to the incomplete combustion of the secondary fuel.

When the load drops, the fuel control valve 9 performs an opening operation to correct the dropped load. Due to this opening operation, although the valve position control signal n of the fuel control valve 9 increases, the distribution ratio of the fuel distribution valves 10 and 11 also changes due to the increase of the valve position control signal n, and the secondary side fuel distribution valve 1
The distribution ratio m to 1 increases.

Therefore, at this point, since the original distribution ratio to the load is deviated, there is a problem that the NOx generation amount increases. This problem will increase as the amount of load drop during switching increases.

Further, when the fuel in this system starts complete combustion due to an increase in the amount of fuel input into the secondary side fuel supply pipe 7, this time, on the contrary, the load increases due to the transition from incomplete combustion to complete combustion. Therefore, in order to return the excessively increased load to the set load, the fuel control valve 9 performs the closing operation.

If the load increase rate at this time is too large, the fuel control valve 9 may be throttled until it becomes below the switching start point. In that case, the switching operation of the fuel distribution valves 10 and 11 is stopped. Resulting in.

By repeating the increase and decrease of the load at the time of fuel switching, the fuel distribution valves 10 and 11 repeatedly open and close alternately, which impairs stable load control of the gas turbine. .

Then, this unstable fuel distribution valve 10, 1
The operation of No. 1 and especially the on / off operation of the gas fuel inflow from the secondary side fuel distribution valve 11 to the combustor 4 also gives a thermal shock to the combustor 4, thereby significantly reducing the life of the combustor 4. There is a problem that ends up. This problem can occur not only when the load is increased but also when the load is decreased by the reverse process.

Further, during normal operation of the gas turbine, the distribution signals m to the fuel distribution valve and the distribution signals of 1-m are proportional to the valve position control signal n.
Due to the minute fluctuations in the distribution ratios, the distribution signals of the distribution ratios m and 1-m fluctuate. In the worst case, the control of the fuel control valve 9 and the fuel distribution valves 10 and 11 may be unstable.

The present invention has been made in consideration of the above-mentioned circumstances, and eliminates the instability of control when switching between two-stage combustion operation,
An object of the present invention is to provide a gas turbine control device capable of performing stable control.

[0037]

In order to solve the above-mentioned problems, the first aspect of the present invention is that a single fuel supply pipe introduced from a gas fuel supply source is branched and one of the branch pipes is a primary pipe. Side fuel supply pipe is connected to the most upstream side of the gas turbine combustor, and the other of the branch pipes is connected as a secondary side fuel supply pipe downstream from the most upstream side of the combustor. In a gas turbine control device that controls the gas fuel supplied from the secondary fuel supply pipe to the combustor to a distribution ratio that reduces the NOx amount of exhaust gas, a total gas fuel is provided at a position upstream of the branch point of the fuel supply pipe. A fuel control valve for setting the supply amount is provided, and a primary side and secondary side fuel distribution valve for setting the distribution ratio of the supply fuel is provided in the primary side and secondary side fuel supply pipes, respectively, and the position of the fuel control valve is set. Belief Has a function generator for setting the distribution ratio to the secondary fuel distribution valve based on the above, and this function generator sharply changes the distribution ratio at the fuel distribution switching point and raises the position signal. It is characterized in that it is set so as to perform a hysteresis operation when descending.

According to a second aspect of the present invention, a comparator for outputting the distribution ratio when the distribution ratio is equal to or less than a set value is provided on the primary side fuel distribution valve side, and the output of this comparator is the primary side. It is characterized by adding to the distribution ratio setting means of the fuel distribution valve.

Further, according to a third aspect of the present invention, as the input signal to the function generator according to the first aspect, a control signal of the fuel control valve which is predetermined based on the load setting signal is generated instead of the position signal of the fuel control valve. A control signal set by another function generator is used.

[0040]

According to the first aspect of the present invention, the distribution ratio to the secondary side fuel distribution valve is sharply changed at the fuel distribution switching point, and the hysteresis operation is set when the position signal rises and falls. As a result, it is possible to minimize the load drop at the time of fuel switching, avoid instability of the control of the fuel control valve, the primary side and secondary side fuel distribution valves, and avoid minute changes during the two-stage combustion operation. In contrast, control instability of the primary side and secondary side fuel distribution valves is not caused.

Further, in the present invention, a comparator for outputting the distribution ratio when the distribution ratio is less than or equal to a set value is provided on the primary fuel distribution valve side, and the output of this comparator is used for the primary fuel distribution valve. Since it was added to the distribution ratio setting means of
While the secondary fuel system is incompletely combusting, the opening degree of the primary fuel distribution valve side is maintained, and it is possible to suppress the decrease of the load during this period as much as possible.

Further, in claim 3, as an input signal to the function generator, instead of the position signal of the fuel control valve,
Since a control signal set by another function generator that generates a predetermined control signal for the fuel control valve based on the load setting signal is used, regardless of the actual control signal for the fuel control valve,
The primary side and secondary side fuel distribution valves are controlled, and it is possible to prevent fluctuations in the opening degree on the fuel control valve side at the start of fuel switching.

[0043]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a system diagram showing a first embodiment of a gas turbine control device according to the present invention. It should be noted that the same or corresponding portions as those of the conventional configuration will be described using the same reference numerals as those in FIG.

The gas turbine controller 20 shown in FIG.
The configuration of the schematic control device is the same as that shown in FIG. 10, and in place of the function generator 12 of FIG. 10, a function generator 21 having a hysteresis (dead zone) particularly at the rise and fall of the switching point is provided. The shape of the hysteresis is a shape that rises sharply such as a step shape or a ramp shape.
FIG. 1 shows a ramp-up shape.

A valve position control signal n for controlling the speed / load of the gas turbine is input to the control device 20, and the fuel control valve 9 is controlled by this valve position control signal n. . The valve position control signal n is input to the primary delay circuit 22, the primary delay circuit 22 is connected to the function generator 21, and the function generator 21 is further connected to the limiter circuit 23.

Further, the function generator 21 is installed in order to suppress the reduction of the gas turbine load due to incomplete combustion immediately after the start of the fuel injection on the secondary side, especially at the time of fuel switching, and after a little after passing the switching point n1. By increasing the distribution ratio m of the secondary side fuel in a step shape or a ramp shape, the secondary side fuel passes through the incomplete combustion area at once and quickly reaches the complete combustion area. As the step amount at this time, the complete combustion region of the secondary fuel, which is previously obtained by a combustion test or the like, is used.

When the load is decreased, the secondary fuel passes through the incomplete combustion region at one time in a process reverse to the above, and the flow rate is switched to zero.

Here, the reason why the function generator 21 has hysteresis when the valve position control signal n rises and falls is that the valve position control signal n is affected by the load fluctuation at the time of switching.
This is to prevent the switching operation / reverse switching operation from occurring due to the fluctuation of the value of.

The primary delay circuit 22 and the limiter circuit 23 are for preventing the fuel distribution valves 10 and 11 from changing not only during fuel switching but also during secondary combustion operation. That is, the distribution ratio m, 1 of the fuel distribution valves 10, 11
-M is a function of the valve position control signal n, but since this signal n is a signal for gas turbine load control, it constantly fluctuates.

Even if this fluctuation is small, it finally changes in the opening degree of the fuel distribution valves 10 and 11. Therefore, in some cases, the fuel control valve 9 side and the fuel distribution valves 10 and 11 side may change. Control instability can occur.

Therefore, the first-order lag circuit 22 is installed to reduce the sensitivity of the valve position control signal n branched to the fuel distribution valve side. Further, the limiter circuit 23 stabilizes the distribution ratio m by limiting the time change rate of the distribution ratio m of the secondary side fuel distribution valve 11 output from the function generator 21, that is, dm / dt. It is installed in.

Next, the operation of this embodiment will be described.

When the load of the gas turbine increases and passes the fuel switching point n1 and reaches the point n2, the distribution ratio m of the secondary side fuel distribution valve 11 is stepped or changed by the function defined by the function generator 21. Ramp up, fuel distribution valve 1
The switching operation at 0 and 11 is started.

In particular, as described above, the secondary side fuel distribution valve 11 rapidly passes through the incomplete combustion region and increases in opening up to the complete combustion region at a time, so that fluctuation in gas turbine load due to switching is minimized. Can be suppressed to This is shown in FIG. 2 (A), and FIG. 2 (B) shows a conventional example.

The step amount of the distribution ratio m at the start of switching or at the completion of switching is a value obtained in advance from the combustor test data or the like as an amount that avoids the incomplete combustion region in the secondary side fuel system as described above.

Furthermore, the valve position control signal n fluctuates in order to control the speed and load of the fuel control valve 9 during the switching operation or during the two-stage combustion.
In particular, even a slight change in the control signal n can minimize the influence on the distribution ratio m, and a stable two-stage combustion operation can be performed.

As an example, FIGS. 3A and 3B show the response of the distribution ratio m to the minute step change of the valve position control signal n during the fuel switching operation. FIG. 3A shows this embodiment, and FIG. 3B shows a conventional example.

As described above, according to the present embodiment, as compared with the conventional example in FIGS. 2 and 3, at the start of fuel switching, among the fuel distribution valves 10 and 11, especially the secondary side fuel distribution valve 11 is performed. Function generator 2 for rapidly passing incomplete combustion
1, the load drop at the time of switching can be minimized, and the fuel control valve 9 and the fuel distribution valves 10, 1 can be installed.
It is possible to provide a control device that avoids the control instability of No. 1 and does not cause the control instability of the fuel distribution valves 10 and 11 even with a minute change during the two-stage combustion operation.

FIG. 4 is a system diagram showing a second embodiment of the gas turbine control device according to the present invention. The same or corresponding parts as those of the first embodiment will be described with the same reference numerals.

In this gas turbine control device 20 ', the above-mentioned load drop is avoided by stopping the closing operation of the primary side fuel distribution valve 10 especially at the fuel switching start point. That is, as shown in FIG. 4, the comparator 24 is installed by branching from the control signal line of the secondary fuel distribution valve 11, and when the preset value m1 or more, the control signal of the distribution ratio m is transmitted to the primary fuel. Input to the distribution valve 10 through the adder 25.

Using this gas turbine controller 20 ',
When m <m1, the distribution signal to the primary side fuel distribution valve 10 is 1-m + m = 1, that is, a full open signal is output. The relationship between the fuel distribution valve opening and the gas turbine load at this time is shown in FIG. According to FIG. 5, while the secondary fuel system is incompletely burning, the opening degree on the primary fuel distribution valve 10 side is maintained, so that it is possible to suppress the decrease in load during this period as much as possible. .

FIG. 6 is a system diagram showing a third embodiment of the gas turbine controller according to the present invention. The same or corresponding parts as those of the first embodiment will be described with the same reference numerals.

In this gas turbine controller 20 ″,
Similar to the first embodiment, this is for avoiding instability of the fuel distribution valve side control due to load reduction at the start of fuel switching.

As shown in FIG. 6, in the present embodiment, a function generator 26 for outputting a pre-calculated control signal n'of the fuel control valve 9 for the load setting P '(control device is not shown) is provided. It is installed and outputs a signal m for controlling the fuel distribution valves 10 and 11 based on the control signal n'obtained by the function generator 26.

As described above, according to this embodiment, the fuel distribution valves 10 and 1 are independent of the actual control signal n of the fuel control valve 9.
1, the fluctuation of the opening degree of the fuel control valve 9 side can be prevented especially at the start of fuel switching.

In the present invention, the above-mentioned respective embodiments can be used in combination. Further, in the above embodiments, a simple type gas turbine system was described as an example of the gas turbine, but the present invention is also applicable to, for example, a combined cycle gas turbine system in which a gas turbine and a steam turbine are combined.

[0068]

As described above, according to the first aspect of the present invention.
According to the method, the distribution ratio to the secondary side fuel distribution valve is rapidly changed at the fuel distribution switching point, and the hysteresis operation is set when the position signal rises / falls. This makes it possible to minimize the instability of the control of the fuel control valve, the primary side and secondary side fuel distribution valves, and to prevent the primary side and secondary side fuels from changing even during minute changes during the two-stage combustion operation. It is possible to provide a stable control device without causing control instability of the distribution valve.

Further, according to claim 2, a comparator for outputting the distribution ratio when the distribution ratio is less than or equal to the set value is provided on the primary fuel distribution valve side, and the output of this comparator is used for the primary fuel distribution. Since it is added to the distribution ratio setting means of the valve, while the secondary fuel system is incomplete combustion, the opening of the primary fuel distribution valve side is maintained, and the decrease in load during this period is suppressed as much as possible. be able to.

Further, according to the third aspect, instead of the position signal of the fuel control valve, the control signal of the fuel control valve which is predetermined based on the load setting signal is generated as the input signal to the function generator. Since the control signal set by the function generator of is used, the primary side and secondary side fuel distribution valves are controlled regardless of the actual control signal of the fuel control valve, and the fuel control valve side at the time of fuel switching start is controlled. It is possible to prevent the opening degree from varying.

[Brief description of drawings]

FIG. 1 is a system diagram showing a first embodiment of a gas turbine control device according to the present invention.

FIG. 2A is a graph showing the opening of the fuel distribution valve and the load decrease during the load increase in the first embodiment, and FIG. 2B is a graph showing the conventional example.

3A is a diagram showing a response of a control signal on the fuel distribution valve side to a slight change in a fuel control valve setting signal in the first embodiment, and FIG. 3B is a diagram showing a conventional example thereof.

FIG. 4 is a system diagram showing a second embodiment of the gas turbine control device according to the present invention.

FIG. 5 is a graph showing the opening of the fuel distribution valve and the load decrease during the load increase in the second embodiment.

FIG. 6 is a system diagram showing a third embodiment of the gas turbine control device according to the present invention.

FIG. 7 is a schematic configuration diagram showing a conventional gas turbine.

8A is a diagram showing a fuel flow rate in each system with respect to a combustion temperature of a gas turbine, FIG. 8B is a diagram showing a fuel flow rate ratio in each system, and FIG. 8C is a diagram showing a NOx generation amount.

FIG. 9 is a diagram showing a fuel flow rate to gas turbine output.

FIG. 10 is a system diagram showing a conventional gas turbine control device.

[Explanation of symbols]

 2 gas turbine 9 fuel control valve 10 primary side fuel distribution valve 11 secondary side fuel distribution valve 13 calculator (distribution ratio setting means) 20 gas turbine control device 21 function generator 22 primary delay circuit 23 limiter circuit 24 comparator 25 addition Unit 26 Function Generator

Claims (3)

[Claims] 1. A fuel supply pipe led from a gas fuel supply source is branched, and one of the branch pipes is connected as a primary fuel supply pipe to the most upstream side of a gas turbine combustor, and
The other of the branch pipes is connected as a secondary fuel supply pipe downstream of the most upstream side of the combustor, and the gas fuel supplied from the primary and secondary fuel supply pipes to the combustor is NOx of the exhaust gas. In the gas turbine control device for controlling the distribution ratio to reduce the amount, a fuel control valve for setting the total gas fuel supply amount is provided at a position upstream of the branch point of the fuel supply pipe, and the primary side and the secondary side are provided. The primary fuel supply valve and the secondary fuel distribution valve that set the distribution ratio of the supplied fuel are provided in the side fuel supply pipe, and the distribution ratio to the secondary fuel distribution valve is set based on the position signal of the fuel control valve. A function generator is provided, which is characterized in that the distribution ratio is sharply changed at the fuel distribution switching point and that the hysteresis operation is performed when the position signal rises and falls. That the gas turbine controller. 2. The primary side fuel distribution valve side is provided with a comparator for outputting the distribution ratio when the distribution ratio is equal to or less than a set value, and the output of the comparator is set to the distribution ratio setting of the primary side fuel distribution valve. The gas turbine control device according to claim 1, wherein the gas turbine control device is added to the means. 3. A function generator that generates a predetermined control signal for the fuel control valve based on a load setting signal, instead of the position signal for the fuel control valve, as an input signal to the function generator. The gas turbine control device according to claim 1, wherein a set control signal is used.