JP3955145B2 - Steam injection gas turbine power generation equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a steam injection type gas turbine power generation facility.
[0002]
[Prior art]
An example of the configuration of a conventional steam injection type gas turbine power generation facility will be described with reference to FIG.
[0003]
In FIG. 3, reference numeral 1 denotes a drum-type exhaust heat recovery boiler. Water supplied from a feed water pump (not shown) is injected into the drum 2, sent from the drum 2 to the evaporation pipe 4 of the evaporator 3, and heated. Return to drum 2 as a mixture of steam and water. The steam generated in the drum 2 is sent to the superheater pipe 8 of the superheater 7 through the steam cutoff valve 5 and the steam control valve 6, further superheated in the superheater 7, passed through the steam injection pipe 9, and the combustor 10. Supplied to. 11 is the chimney of boiler 1.
[0004]
In addition, gas turbine fuel is supplied to the combustor 10 through the fuel control valve 14, and further compressed air is supplied from the compressor 15. The combustor 10 burns the gas turbine fuel in the compressed air. Thus, the steam supplied from the boiler 1 through the steam injection pipe 9 is further superheated and supplied to the gas turbine 16 together with the combustion gas, and the gas turbine 16 is rotated. The compressor 15 is connected to a gas turbine 16. Exhaust gas from the compressor 15 (gas turbine 16) is guided to the boiler 1, and steam is generated by the heat energy.
[0005]
Further, the gas turbine 16 is connected to the generator 18 via the speed reducer 17, and the generator 18 rotates to generate electric power when the gas turbine 16 rotates.
The steam shut-off valve 5 is of an air drive type, and an air supply valve 19 composed of an electromagnetic valve for supplying driving air to the steam shut-off valve 5 is provided. The air supply valve 19 and the steam control valve 6 are controlled by an injection steam control device 20, and the fuel control valve 14 is controlled by a fuel control device 22.
[0006]
The control when the load connected to the generator 18 is shut off by the injection steam control device 20 and the fuel control device 22 will be described.
When shutting off heavy loads (over 80% of the capacity of the gas turbine 16);
The gas turbine 16 and the generator 18 are stopped to prevent overspeed. That is, the steam control valve 20 is fully closed by the injection steam control device 20 via the air supply valve 19, the steam control valve 6 is fully closed, and the fuel control device 22 is throttled to the minimum by the fuel control device 22, so that the combustor. Minimize 10 flames.
[0007]
When light loads (less than 80% of the capacity of the gas turbine 16) are interrupted;
The steam control valve 6 is throttled by the injection steam control device 20 and the fuel control valve 14 is throttled by the fuel control device 22 to control the amount of steam flowing into the combustor 10 and the amount of gas turbine fuel to prevent overspeed.
[0008]
As shown in FIG. 3, in order to prevent water droplets from entering the gas turbine 16, the superheater tube 8 of the superheater 7 is provided with a first steam drain valve 23 made of an electromagnetic valve. A second steam drain valve 24 comprising an electromagnetic valve is provided.
[0009]
[Problems to be solved by the invention]
However, when the heavy load (80% or more of the capacity of the gas turbine 16) is interrupted, the amount of steam remaining in the superheater tube 8 and the steam injection tube 9 of the superheater 7 is large, so the amount of steam injected into the combustor 10 Since the speed does not decrease suddenly, the speed cannot be sufficiently controlled and there is a risk of overspeed. In addition, the flame that has been minimized by the steam injected into the combustor 10 may be extinguished. Further, if the overspeed occurs or the flame disappears, the gas turbine 16 is tripped, so the operator must restart the gas turbine 16 when the load is interrupted and tripped. It was.
[0010]
Therefore, an object of the present invention is to provide a steam injection type gas turbine power generation facility that can prevent an overspeed of the gas turbine at the time of load interruption and can prevent a flame of a combustor from disappearing.
[0011]
[Means for Solving the Problems]
In order to achieve the above-described object, the invention according to claim 1 of the present invention includes a boiler, a gas turbine connected to a generator, and steam supplied from the boiler by burning supplied fuel. A combustor for heating and supplying to the gas turbine is provided, and a steam shut-off valve is provided at an inlet of steam supplied from the boiler of the combustor, and the steam shut-off valve is fully closed when the load of the generator is shut off. It is characterized by doing.
[0012]
According to the above configuration, the steam injected into the combustor is substantially shut off by fully closing the steam shut-off valve at the combustor inlet when the load of the generator is shut off. Therefore, the overspeed of the gas turbine is prevented and the disappearance of the flame of the combustor is prevented.
[0013]
According to a second aspect of the present invention, there is provided a drum-type boiler having a superheater, a gas turbine connected to a generator, combustion of supplied fuel and heating steam supplied from the boiler, and the gas turbine Equipped with a combustor to supply
A steam pipe between the boiler drum and the boiler superheater is provided with a primary steam cutoff valve and a steam control valve, and a secondary steam cutoff valve is provided in the steam pipe between the boiler superheater and the combustor. A first steam drain valve is connected to a superheat pipe of the boiler superheater, a second steam drain valve is connected to a steam pipe between the boiler superheater and a secondary steam cutoff valve, and the power generation When the load of the machine is shut off, the primary steam shut-off valve, the steam control valve, the secondary steam shut-off valve, the first steam drain valve, and the second steam drain valve are driven in combination to shift to no-load operation. To do.
[0014]
According to the above configuration, when the generator load is shut off, the primary steam shut-off valve, the steam control valve, the secondary steam shut-off valve, the first steam drain valve, and the second steam drain valve are driven in combination. By shifting to the load operation, the trip of the gas turbine is prevented and the time until the load operation is shortened.
According to a third aspect of the present invention, there is provided a drum boiler having a superheater, a gas turbine connected to a generator, combustion of supplied fuel and heating of steam supplied from the boiler to the gas turbine. A steam pipe provided between the boiler superheater and the combustor, wherein the steam pipe between the boiler drum and the boiler superheater includes a primary steam cutoff valve and a steam control valve. A secondary steam shut-off valve, a first steam drain valve connected to the superheater pipe of the boiler superheater, and a second steam drain connected to the steam pipe between the boiler superheater and the secondary steam shutoff valve. A valve is connected, and when the load of the generator is shut off, the primary steam shutoff valve, the steam control valve, and the secondary steam shutoff valve are closed, the first steam drain valve and the second steam drain valve are opened, and the load The primary steam shut-off valve and steam control as the specified time elapses from shut-off A valve and a secondary steam shut-off valve are opened, the first steam drain valve and the second steam drain valve are closed, and steam for maintaining the number of revolutions necessary for no-load operation of the generator is injected into the combustor, It is characterized by shifting to no-load operation.
According to the above configuration, when the load on the generator is shut off, the primary steam shutoff valve, the steam control valve, and the secondary steam shutoff valve are closed, and the first steam drain valve and the second steam drain valve are opened. As the specified time elapses, the primary steam shutoff valve, steam control valve, and secondary steam shutoff valve are opened, the first steam drain valve and the second steam drain valve are closed, and the number of revolutions required for no-load operation of the generator is set. The steam to be maintained is injected into the combustor and shifted to no-load operation.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the structure same as FIG. 3 of a prior art example, and description is abbreviate | omitted.
[0016]
FIG. 1 is a configuration diagram of a steam injection type gas turbine power generation facility according to an embodiment of the present invention.
The steam injection type gas turbine power generation facility of the present invention is provided with a pneumatic secondary steam cutoff valve 31 at the inlet position of the combustor 10 of the steam injection pipe 9. The secondary steam cutoff valve 31 is provided with a secondary air supply valve 34 composed of an electromagnetic valve for supplying driving air. The secondary air supply valve 34 of the secondary steam cutoff valve 31, the air supply valve 19, the steam control valve 31, the first steam drain valve 23, and the second steam drain valve 24 of the (primary) steam cutoff valve 5 are injected. It is controlled by the steam control device 20 ′.
[0017]
The control at the time of load interruption by the injected steam control device 20 ′ will be described with reference to FIG.
1. Simultaneously with the occurrence of load shutoff, the secondary air shutoff valve 31 and the primary steam shutoff valve 5 are driven by driving the secondary air shutoff valve 31 of the secondary steam shutoff valve 31 and the air supply valve 19 of the primary steam shutoff valve 5. The steam control valve 6 is forcibly closed and the steam injected into the combustor 10 is shut off. (At the same time as the occurrence of load shut-off, the fuel control device 22 minimizes the fuel control valve 14 to minimize the flame of the combustor 10.) As a result, the steam injected into the combustor 10 is substantially shut off and the fuel By giving priority to the speed control by the control, the overspeed of the gas turbine 6 is prevented, and even if the flame of the combustor 10 is minimized, the disappearance of the flame of the combustor 10 is prevented, and the operation shifts to the no-load operation. .
2. Simultaneously with the occurrence of load interruption, the first steam drain valve 23 and the second steam drain valve 24 are opened. Thereby, the superheater tube 8 and the steam injection tube 9 of the superheater 7 are released, and abnormal pressure increase is prevented.
3. Next, when a predetermined time (for example, 30 seconds) elapses from the load cutoff, the secondary steam cutoff valve 31 is gradually opened. Thereby, the disappearance of the flame of the combustor 10 due to the residual pressure is prevented.
4). Next, when a specified time (for example, 50 seconds) elapses from the load cutoff, the primary steam cutoff valve 5 is opened and the steam control valve 6 is opened about 5%. The supply of steam from the boiler 1 is started.
5). Next, when a predetermined time (for example, 60 seconds) elapses after the load is cut off, the first steam drain valve 23 and the second steam drain valve 24 are closed. As a result, steam corresponding to an opening degree of 5% of the steam control valve 6 is injected into the combustor 10 and the rotational speed necessary for the no-load operation of the generator 18 is maintained.
6). Next, when a specified time (for example, 90 seconds) elapses from the load interruption and the generator 18 is connected to the load again, the steam control valve 6 is gradually opened. As a result, the amount of steam supplied to the combustor 10 gradually increases.
7). Next, the steam control valve 6 is automatically turned on to shift to automatic load operation.
[0018]
In this way, the steam injected into the combustor 10 can be substantially shut off by interposing the secondary steam shut-off valve 31 in the steam injection pipe 9 and fully closing the secondary steam shut-off valve 31 when the load is shut off. Therefore, the overspeed of the gas turbine 16 can be prevented, and even when the flame of the combustor 10 is minimized, the disappearance of the flame can be prevented and the trip of the gas turbine 16 can be prevented. In addition, since the gas turbine 16 can reliably shift to the no-load operation without tripping, the time until the load operation is started can be shortened.
[0019]
In addition, after the load is cut off, each valve is operated in a program manner, so that no-load operation can be maintained and the load operation can be resumed.
[0020]
【The invention's effect】
As described above, according to the present invention, the steam injected into the combustor when the load is interrupted can be substantially interrupted, so that the overspeed of the gas turbine and the disappearance of the flame of the combustor can be prevented, and the trip of the gas turbine can be prevented. .
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a steam injection gas turbine power generation facility according to an embodiment of the present invention.
FIG. 2 is a characteristic diagram showing the operation of each valve in the steam injection type gas turbine power generation facility.
FIG. 3 is a configuration diagram of a conventional steam injection gas turbine power generation facility.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Boiler 2 Drum 3 Evaporator 4 Evaporation pipe 5 Primary steam cutoff valve 6 Steam control valve 7 Superheater 8 Superheat pipe 9 Steam injection pipe
10 Combustor
15 Compressor
16 Gas turbine
17 Reducer
18 Generator
20 'Injection steam control device
21 Fuel control system
23 First steam drain valve
24 Second steam drain valve
31 Secondary steam shutoff valve

Claims (3)

With a boiler,
A gas turbine coupled to a generator;
A combustor for combusting the supplied fuel to heat the steam supplied from the boiler and supplying the steam to the gas turbine;
A steam injection type gas turbine power generation facility characterized in that a steam cutoff valve is provided at an inlet of steam supplied from the boiler of the combustor, and the steam cutoff valve is fully closed when the load of the generator is shut off. A drum boiler having a superheater;
A gas turbine coupled to a generator;
Combusting the supplied fuel, heating the steam supplied from the boiler, and providing a combustor for supplying to the gas turbine,
A steam pipe between the boiler drum and the boiler superheater is provided with a primary steam cutoff valve and a steam control valve,
A secondary steam shut-off valve is installed in the steam pipe between the boiler superheater and the combustor;
A first steam drain valve is connected to the superheater tube of the boiler superheater;
A second steam drain valve is connected to the steam pipe between the boiler superheater and the secondary steam shut-off valve;
When the load of the generator is shut off, the primary steam shut-off valve, the steam control valve, the secondary steam shut-off valve, the first steam drain valve, and the second steam drain valve are driven in combination to shift to no-load operation. A steam injection type gas turbine power generation facility. A drum boiler having a superheater;
A gas turbine coupled to a generator;
A combustor for combusting the supplied fuel to heat the steam supplied from the boiler and supplying the steam to the gas turbine;
A steam pipe between the boiler drum and the boiler superheater is provided with a primary steam cutoff valve and a steam control valve,
A secondary steam shut-off valve is installed in the steam pipe between the boiler superheater and the combustor;
A first steam drain valve is connected to the superheater tube of the boiler superheater;
A second steam drain valve is connected to the steam pipe between the boiler superheater and the secondary steam shut-off valve;
When the load of the generator is shut off, the primary steam shut-off valve, the steam control valve, and the secondary steam shut-off valve are closed, the first steam drain valve and the second steam drain valve are opened, and a predetermined time from when the load is shut off. The primary steam shut-off valve, the steam control valve, and the secondary steam shut-off valve are opened as the time elapses, and the first steam drain valve and the second steam drain valve are closed. Inject steam to maintain the above into the combustor and shift to no-load operation
A steam-injection type gas turbine power generation facility.

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