JP2018173004A - Stop method for gas turbine, control device for gas turbine, and gas turbine plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To safely stop a gas turbine while suppressing damage of an apparatus, and to bring the gas turbine into a stop state within a short time.SOLUTION: A stop method for a gas turbine executes a first suction amount decrease step (S4), a suction amount keeping step (S6) and a second suction amount decrease step (S8). In the first suction amount decrease step (S4), when a stop condition for stopping the gas turbine is satisfied (ECs), a suction amount adjuster is driven in such a manner that a suction amount of air sucked by a compressor of the gas turbine is decreased. In the suction amount keeping step (S6), when a suction amount keeping condition is satisfied during the execution of the first suction amount decrease step (S4), the drive of the suction amount adjuster is stopped. In the second suction amount decrease step (S8), when a cancellation condition is satisfied during the execution of the suction amount keeping step (S6), the suction amount adjuster is driven in such a manner that the suction amount is decreased until the suction amount adjuster is brought into a gas turbine stop time state.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a gas turbine stop method, a gas turbine control device, and a gas turbine plant.

  The gas turbine includes a compressor that compresses air, a combustor that generates a combustion gas by burning fuel in the air compressed by the compressor, and a turbine that is driven by the combustion gas. Many of the compressors include a compressor rotor, a compressor casing that covers the outer periphery of the compressor rotor, and an inlet guide vane (hereinafter referred to as IGV) device that adjusts the flow rate of air flowing into the compressor casing. A generator is usually connected to the gas turbine rotor of such a gas turbine.

  In the gas turbine of the following patent document 1, a method of maintaining the opening degree of the IGV at the time of load interruption after load interruption is disclosed.

JP-A-08-004555

  In the gas turbine field, when the gas turbine is stopped, it is required to stop the gas turbine in as short a time as possible from the operational aspect. If the technique described in Patent Document 1 is applied to stop the gas turbine, the flow rate of the working fluid flowing in the gas turbine is maintained even after the load is interrupted. The time until the turbine stops becomes longer.

  Accordingly, an object of the present invention is to provide a gas turbine stopping method capable of stopping the gas turbine safely while suppressing damage to the equipment and capable of stopping the gas turbine in a short time.

A method for stopping a gas turbine as one aspect according to the invention for achieving the above object is as follows:
A compressor that compresses air, a combustor that generates combustion gas by burning fuel in the air compressed by the compressor, and a turbine that is driven by the combustion gas, the compressor having an axis A compressor rotor that rotates around the compressor rotor, a compressor casing that covers an outer peripheral side of the compressor rotor, and an intake air amount regulator that adjusts an intake air amount of air flowing into the compressor casing. In the stop method, when a predetermined stop condition is not satisfied, a normal intake air amount control step for driving the intake air amount controller so that the intake air amount becomes a target intake air amount, and the stop condition is satisfied Then, when a predetermined intake air amount holding condition is satisfied during the execution of the first intake air amount reduction step for driving the intake air amount regulator and the first intake air amount reduction step so that the intake air amount decreases, When a predetermined release condition is satisfied during execution of the intake air amount holding step for stopping the drive of the intake air amount adjuster and the intake air amount holding step, until the intake air amount adjuster is in a gas turbine stop state, And a second intake air amount reduction step of driving the intake air amount adjuster so as to reduce the intake air amount.

  When the gas turbine stop condition is satisfied, immediately if the intake air regulator is brought into the gas turbine stop state, the possibility of occurrence of surging in the compressor increases. In the stop method, even when the stop condition is satisfied, the intake air amount regulator is not immediately put into the gas turbine stop state, and the drive of the intake air amount controller is stopped halfway. For this reason, in the said stop method, the surging generation | occurrence | production in a compressor can be suppressed.

  By the way, when the stop condition is satisfied, the occurrence of surging in the compressor can also be suppressed by maintaining the intake air amount regulator in the state at the time when the stop condition is satisfied. However, in this method, the flow rate of air flowing in the gas turbine increases, and it takes time until the gas turbine is stopped. In the stop method, when the stop condition is satisfied, first, a first intake air amount reduction process for driving the intake air amount regulator is executed so that the intake air amount decreases. For this reason, in the said stop method, time until a gas turbine will be in a stop state can be shortened.

  Here, in the method for stopping the gas turbine, the intake air amount regulator is configured to operate at a maximum load when the maximum load is applied to the gas turbine and a minimum when the minimum load is applied to the gas turbine. A state during load operation, a state during no load operation when no load is applied to the gas turbine, a state when the gas turbine is stopped, and a state between these states, the state during the no load operation Is a state in which the intake air amount can be made larger than in the gas turbine stop state, and the minimum load operation state is a state in which the intake air amount can be made larger than the no-load operation state. The maximum load operation state is a state in which the intake air amount can be increased more than the minimum load operation state, and the intake air amount holding condition is determined by the intake air amount controller It is a no-load operation state or the may be a made that state, between the no-load operation state and the minimum load operation state.

  In the gas turbine stop method, the intake air amount maintaining condition is that the intake air amount controller is in a state between the no-load operation state and the minimum load operation state, and the no-load operation is performed. It may be the state on the state side of the minimum load operation than the intermediate state between the hour state and the minimum load operation state.

  Further, in any one of the above gas turbine stopping methods, the release condition is that the rotation speed of the compressor rotor is a rotation corresponding to a predetermined ratio with respect to the rated rotation speed rather than the rated rotation speed of the compressor. It may be that the number of revolutions is lower by several minutes.

  In any of the above gas turbine stopping methods, the release condition may be that the discharge pressure of the compressor has decreased to a predetermined release discharge pressure.

  In the gas turbine stopping method according to any one of the above, the compressors are arranged with a compressor rotor shaft that is long in an axial direction in which the axial line extends around the axis, and spaced apart from each other in the axial direction. A plurality of rotor blade rows fixed to the compressor rotor shaft, and the compressor casing has an inlet formed at an end upstream of the axis that is one side in the axial direction, and the axis A discharge port is formed at an end on the downstream side of the axis that is opposite to the upstream side, and the intake air amount regulator includes at least the inlet guide blade device among an inlet guide blade device and a variable stator blade device. The inlet guide vane device is disposed in the air flow path in the compressor casing, and is arranged on the upstream side of the first moving blade row on the upstream side of the axis among the plurality of moving blade stages, Inlet plan attached to the compressor casing A blade driving mechanism for displacing the inlet guide blade, and the variable stationary blade device is in an air flow path in the compressor casing and is between a plurality of blade rows. And a stationary blade that is disposed between the stationary blades and attached to the compressor casing, and a blade driving mechanism that displaces the stationary blade.

  In the gas turbine stopping method, the intake air amount regulator includes the inlet guide vane device and the variable stationary vane device. In the intake air amount holding step, the inlet guide vane device and the variable air guide are provided. The driving state with the stationary blade device may be different.

  Further, in any one of the above-described gas turbine stopping methods, the gas turbine is provided with an extraction mechanism that extracts air from the compressor casing and exhausts the air outside the compressor casing, and after the intake amount holding step, the extraction mechanism Accordingly, an extraction process for exhausting air from the compressor casing may be executed.

  Further, in any one of the gas turbine stopping methods described above, a plurality of extraction mechanisms for extracting air from the compressor casing and exhausting it out of the compressor casing are provided, and the plurality of extraction mechanisms include the compression mechanism The extraction positions for extracting air from the inside of the machine casing are different from each other in the axial direction, and after the intake amount holding step, the air is exhausted from the inside of the compressor casing by any one of the plurality of extraction mechanisms. The bleeding step is performed, and the bleeding step is performed by the rear bleed mechanism at the most downstream side in the axial direction among the plurality of bleeder mechanisms during the intake amount holding step. After exhausting the air from the inside and performing the first bleed process in which the remaining bleed mechanism does not evacuate the air from the compressor casing and the second intake amount reducing process Among the plurality of bleed mechanisms, among the plurality of bleed mechanisms, the bleed position is exhausted from the compressor casing by the upstream bleed mechanism on the most upstream side in the axial direction, and the remaining bleed mechanisms are: A second extraction step in which air is not exhausted from the compressor casing.

A control apparatus for a gas turbine as one aspect according to the invention for achieving the above object is as follows:
A compressor that compresses air, a combustor that generates combustion gas by burning fuel in the air compressed by the compressor, and a turbine that is driven by the combustion gas, the compressor having an axis A compressor rotor that rotates around the compressor rotor, a compressor casing that covers an outer peripheral side of the compressor rotor, and an intake air amount regulator that adjusts an intake air amount of air flowing into the compressor casing. In the control device, when a predetermined stop condition is not satisfied, a normal intake air amount control unit that drives the intake air amount controller so that the intake air amount becomes a target intake air amount, and the stop condition is satisfied A stop transition control unit that drives the intake air amount adjuster according to a condition, and the stop transition control unit adjusts the intake air amount so that the intake air amount decreases when the stop condition is satisfied. A first intake air amount reducing step for driving the intake device, and an intake air amount holding step for stopping the drive of the intake air amount adjuster when a predetermined intake air amount holding condition is satisfied during the execution of the first intake air amount reducing step; When the predetermined release condition is satisfied during execution of the intake air amount holding step, the intake air amount adjuster is set so that the intake air amount decreases until the intake air amount adjuster enters a gas turbine stop state. And a second intake air amount reduction step of driving.

A gas turbine plant as one aspect according to the invention for achieving the above object is as follows:
A gas turbine; and a control device that controls the gas turbine, wherein the gas turbine generates a combustion gas by combusting fuel in the air compressed by the compressor and the air compressed by the compressor. A compressor that rotates around an axis, a compressor casing that covers an outer peripheral side of the compressor rotor, and the compressor casing. An intake air amount adjuster that adjusts an intake air amount of air flowing into the controller, and the control device sets the intake air amount to a target air intake air amount when a predetermined stop condition is not satisfied. A normal intake air amount control unit that drives the intake air amount adjuster, and a stop transition control unit that drives the intake air amount controller according to the condition when the stop condition is satisfied, and the stop transition control Is a predetermined intake air amount during the execution of the first intake air amount reducing step for driving the intake air amount regulator and the first intake air amount reducing step so that the intake air amount is reduced when the stop condition is satisfied. When the holding condition is satisfied, the intake air amount controller is configured to stop the driving of the intake air amount adjuster, and when a predetermined release condition is satisfied during the execution of the intake air amount holding step, the intake air amount controller And a second intake air amount reduction step of driving the intake air amount adjuster so as to reduce the intake air amount until a stop state is reached.

  Here, in the gas turbine plant, the intake air amount regulator includes a maximum load operation state when a maximum load is applied to the gas turbine and a minimum load operation when a minimum load is applied to the gas turbine. And a state during no load operation when the gas turbine is not loaded, a state when the gas turbine is stopped, and a state between these states, and the state during the no load operation is The state in which the intake air amount can be made larger than that in the gas turbine stop state, and the minimum load operation state is a state in which the intake air amount can be made larger than the no-load operation state, The maximum load operation state is a state in which the intake air amount can be made larger than the minimum load operation state, and the intake air amount holding condition is determined by the intake air amount controller, It is a load operation state or the may be to a state between the minimum load operation state and the non-load operation state.

  Further, in the gas turbine plant, the intake air amount holding condition is a state between the no-load operation state and the minimum load operation state when the intake air amount regulator is in the no-load operation state. And an intermediate state between the minimum load operation state and the minimum load operation state side.

  In any of the above gas turbine plants, the gas turbine plant further includes a rotation speed meter that detects the rotation speed of the compressor rotor, and the release condition is that the rotation speed of the compressor rotor detected by the rotation speed meter is The rotational speed may be lower than the rated rotational speed of the compressor by a rotational speed corresponding to a predetermined ratio with respect to the rated rotational speed.

  In any of the above gas turbine plants, the gas turbine plant includes a discharge pressure gauge that detects a discharge pressure of the compressor, and the release condition is that the discharge pressure detected by the discharge pressure gauge is a predetermined release discharge pressure. It may have fallen to.

  In any one of the gas turbine plants described above, the compressor rotor is aligned with the compressor rotor shaft that is long in the axial direction in which the axial line extends around the axis, and spaced apart from each other in the axial direction. A plurality of rotor blade rows fixed to a compressor rotor shaft, and the compressor casing has an intake port formed at an end on the upstream side of the axis that is one side in the axial direction, and the upstream side of the axis A discharge port is formed at the end on the downstream side of the axis that is opposite to the inlet, and the intake air amount regulator includes at least the inlet guide blade device among an inlet guide blade device and a variable stator blade device, The inlet guide vane device is arranged in the air flow path in the compressor casing, and is arranged on the upstream side of the first moving blade row on the upstream side of the axial line among the plurality of moving blade rows, and Inlet attached to the machine casing An inner blade and a blade drive mechanism for displacing the inlet guide blade, and the variable stationary blade device is in an air flow path in the compressor casing and is between a plurality of moving blade rows. Thus, it may have a stationary blade disposed between the stator blades and attached to the compressor casing, and a blade driving mechanism for displacing the stationary blades.

  In the gas turbine plant, the intake air amount adjuster includes the inlet guide blade device and the variable stationary blade device, and the stop transition control unit is configured to perform the intake guide blade device in the intake air amount holding step. And the variable stationary blade device may be driven differently.

  Further, in any one of the above gas turbine plants, an air extraction mechanism for extracting air from the compressor casing and exhausting it outside the compressor casing, the control device, after the intake air amount holding step, You may have an extraction control part which performs the extraction process which exhausts air from the inside of the said compressor casing by the said extraction mechanism.

  Further, in any one of the above gas turbine plants, the gas turbine plant includes a plurality of extraction mechanisms that extract air from the compressor casing and exhaust the air out of the compressor casing, and the plurality of extraction mechanisms include the compressor casing. The extraction positions for extracting the air from the inside are different from each other in the axial direction, and the control device performs air from the inside of the compressor casing by one of the plurality of extraction mechanisms after the intake amount holding step. A bleed control unit that executes a bleed process for evacuating the bleed air, wherein the bleed process has a bleed position at the most downstream side in the axial direction of the plurality of bleed mechanisms during execution of the intake amount holding process. A first extraction step in which air is exhausted from the compressor casing by a subsequent extraction mechanism, and the remaining extraction mechanisms do not exhaust air from the compressor casing; After the second intake amount reduction step, among the plurality of bleed mechanisms, out of the compressor casing, the bleed position of the plurality of bleed mechanisms is the most upstream of the bleed position in the axial direction on the upstream side of the axis. The remaining bleed mechanism may include a second bleed process in which air is not evacuated from the inside of the compressor casing.

  In one embodiment of the present invention, the gas turbine can be stopped safely while suppressing damage to the equipment, and the gas turbine can be stopped in a short time.

It is explanatory drawing which shows the structure of the gas turbine plant in 1st embodiment which concerns on this invention. It is a functional block diagram of the control apparatus in 1st embodiment which concerns on this invention. It is a graph which shows the relationship between the fuel flow volume and IGV opening degree in 1st embodiment which concerns on this invention. It is a flowchart which shows operation | movement of the control apparatus in 1st embodiment which concerns on this invention. In 1st embodiment which concerns on this invention, it is a graph which shows the change of IGV opening degree when the driving | running state of a gas turbine changes from a maximum load driving | running state to a no-load driving | running state. In the first embodiment according to the present invention, it is a graph showing a change in the IGV opening when the stop condition is satisfied in the process in which the operation state of the gas turbine is changing from the maximum load operation state to the no load operation state. . It is a graph which shows the change of the operating point of a compressor when the operation state of a gas turbine changes from a maximum load operation state to a no-load operation state in a first embodiment according to the present invention. The graph which shows the change of the operating point of the compressor when the stop condition is satisfied in the process in which the operation state of the gas turbine is changing from the maximum load operation state to the no load operation state in the first embodiment according to the present invention. It is. It is a graph which shows the characteristic of a general compressor. It is explanatory drawing which shows the structure of the gas turbine plant in 2nd embodiment which concerns on this invention. It is a functional block diagram of the control apparatus in 2nd embodiment which concerns on this invention. It is explanatory drawing which shows the structure of the gas turbine plant in 3rd embodiment which concerns on this invention. It is a functional block diagram of the control apparatus in 3rd embodiment which concerns on this invention.

  Hereinafter, various embodiments of a gas turbine plant according to the present invention will be described in detail with reference to the drawings.

"First embodiment"
The gas turbine plant as the first embodiment will be described with reference to FIGS.

  As shown in FIG. 1, the gas turbine plant of the present embodiment includes a gas turbine 10, a generator 60 that generates electric power by driving the gas turbine 10, and a control device 100.

  The gas turbine 10 includes a compressor 20 that compresses air A to generate compressed air, a combustor 40 that generates high-temperature combustion gas by burning fuel F in the compressed air, and a turbine 50 that is driven by the combustion gas. It is equipped with.

  The compressor 20 includes a compressor rotor 21 that rotates about an axis Ar, a compressor casing 24 that covers the compressor rotor 21, a plurality of stationary blade rows 27, and an intake air amount adjuster 30. The turbine 50 includes a turbine rotor 51 that rotates about an axis Ar, a turbine rotor 51 that covers the turbine rotor 51, and a plurality of stationary blade rows 57.

  The compressor rotor 21 and the turbine rotor 51 are located on the same axis Ar and are connected to each other to form the gas turbine rotor 11. The gas turbine rotor 11 is connected to a rotor 61 of a generator 60. The gas turbine 10 further includes an intermediate casing 15 disposed between the compressor casing 24 and the turbine rotor 51. The combustor 40 is attached to the intermediate casing 15. The compressor casing 24, the intermediate casing 15, and the turbine casing 54 are connected to each other to form the gas turbine casing 14. In the following, the direction in which the axis Ar extends is referred to as an axial direction Da, the circumferential direction around the axis Ar is simply referred to as the circumferential direction Dc, and the direction perpendicular to the axis Ar is referred to as the radial direction Dr. In the axial direction Da, the compressor 20 side is defined as the axial upstream side Dau and the opposite side as the axial downstream side Dad with respect to the turbine 50 as a reference.

  The compressor rotor 21 includes a rotor shaft 22 that extends in the axial direction Da around the axis line Ar, and a plurality of blade rows 23 that are attached to the rotor shaft 22. The plurality of rotor blade rows 23 are arranged in the axial direction Da. Each rotor blade row 23 is composed of a plurality of rotor blades arranged in the circumferential direction Dc. A stationary blade row 27 is arranged on each axial upstream side Dau of the plurality of blade rows 23. Each stationary blade row 27 is provided inside the compressor casing 24. Each stationary blade row 27 is configured by a plurality of stationary blades arranged in the circumferential direction Dc. Therefore, this compressor 20 is an axial flow compressor.

  The end of the compressor casing 24 on the axial upstream side Dau is open. This opening forms an intake port 25. Moreover, the end of the axial downstream side Dad of the compressor casing 24 is also opened. This opening forms a discharge port 26.

  The intake air amount adjuster 30 has an inlet guide vane device 31. The inlet guide vane device 31 includes a plurality of inlet guide vanes (hereinafter referred to as “IGV”) 32 and a blade driving mechanism 33 that displaces the plurality of IGVs 32. The plurality of IGVs 32 are arranged in the compressor casing 24 and are arranged on the upstream side Dau of the plurality of moving blade rows 23 relative to the first moving blade row 23a on the most upstream side of the axis Dau. The plurality of IGVs 32 are arranged in the circumferential direction Dc similarly to the plurality of stator blades constituting one stator blade row 27. The blade drive mechanism 33 rotates each IGV 32 around the blade rotation axis of each of the plurality of IGVs 32 extending in the radial direction Dr from the axis Ar, and changes the opening degree of each IGV 32.

  The compressor has a characteristic relationship between the intake air flow rate of the gas sucked by the compressor and the pressure ratio (= discharge pressure / intake pressure) in the compressor 20. Therefore, as shown in FIG. 9, as a means for indicating the characteristics of the compressor, the characteristics of the compressor may be indicated by a graph in which the corrected intake air amount is taken on the horizontal axis and the pressure ratio is taken on the vertical axis. When the rotational speed is constant, the compressor generally has a characteristic that the pressure ratio gradually decreases as the intake air amount increases. A curve indicating this characteristic is generally called a choke line Lc. In FIG. 9, for the sake of convenience, three choke lines Lc1, Lc2, and Lc3 when the rotation speed N of the compressor is different from each other are illustrated. The choke line Lc1 is a choke line when the rotation speed of the compressor is N1. The choke line Lc2 is a choke line when the rotation speed of the compressor is N2 (<N1). The choke line Lc3 is a choke line when the rotation speed of the compressor is N3 (<N2). The corrected intake air amount is a flow rate obtained by correcting the actual mass flow rate of the suction gas sucked by the compressor in accordance with the state (temperature or pressure) of the suction gas.

  The compressor is operated at a point on the choke line Lc. For this reason, the point on the choke line Lc is called an operating point. A point on the choke line Lc having the highest pressure ratio and the smallest corrected intake air amount, that is, an end point of the choke line Lc is an operating point at which surging can occur in the compressor. Therefore, a line connecting the end points of the plurality of choke lines Lc1, Lc2, and Lc3 is called a surging line Ls. This surging line Ls is a downward-sloping curve. That is, the surging line Ls is a curve in which the pressure ratio decreases as the corrected intake air amount decreases. The choke line Lc shifts to the side where the corrected intake air amount decreases as the rotational speed of the compressor decreases. For this reason, as the rotational speed of the compressor decreases, the position of the intersection with the choke line Lc corresponding to the rotational speed on the surging line Lc also shifts to the side where the corrected intake air amount decreases.

  Surging is a vibration phenomenon accompanied by pressure fluctuations and backflow in the compressor. When this surging occurs, the compressor rotor may be damaged. For this reason, the compressor is required to operate at an operating point in a region where the pressure ratio is smaller and the intake air amount is larger than the surging line Ls in the graph of FIG.

  Again, the structure of a gas turbine plant is demonstrated using FIG.

  The turbine rotor 51 of the turbine 50 includes a rotor shaft 52 extending in the axial direction Da around the axis line Ar, and a plurality of rotor blade rows 53 attached to the rotor shaft 52. The plurality of blade rows 53 are arranged in the axial direction Da. Each rotor blade row 53 is composed of a plurality of rotor blades arranged in the circumferential direction Dc. A stationary blade row 57 is disposed on each axial upstream side Dau of the plurality of blade rows 53. Each stationary blade row 57 is provided inside the turbine casing 54. Each stationary blade row 57 is composed of a plurality of stationary blades arranged in the circumferential direction Dc.

  A fuel line 41 extending from the fuel supply source is connected to the combustor 40. The fuel line 41 is provided with a fuel flow rate adjustment valve 42.

  The generator 60 is electrically connected to the external power system 65 through a power line 62. In the power line 62, a circuit breaker 63 and a transformer 64 are provided.

  The gas turbine plant of the present embodiment further includes a rotation speed meter 80, a vibration meter 81, a discharge pressure gauge 82, and an exhaust thermometer 83. The rotation speed meter 80 detects the rotation speeds of the generator rotor 61 and the gas turbine rotor 11. The vibrometer 81 detects the amplitude of vibration of the generator rotor 61 and the gas turbine rotor 11. The discharge pressure gauge 82 detects the pressure of the compressed air flowing out from the discharge port 26 of the compressor casing 24. The discharge pressure gauge 82 is provided in the intermediate casing 15 into which compressed air from the discharge port 26 of the compressor casing 24 flows. The exhaust thermometer 83 detects the temperature of the combustion gas that has passed through the last moving blade row 53 a on the most downstream side Dad among the plurality of moving blade rows 53 in the turbine rotor 51.

  As shown in FIG. 2, the control device 100 includes an input unit 101, a stop condition determination unit 102, a fuel control unit 103, and an intake air amount control unit 104. The input unit 101 receives data, instructions, and the like. Data received by the input unit 101 includes the number of revolutions detected by the tachometer 80, the amplitude of vibration detected by the vibration meter 81, the discharge pressure detected by the discharge pressure gauge 82, the temperature detected by the exhaust thermometer 83, and the like. The input unit 101 also receives a start command and a stop command input by an operator of the gas turbine plant, a load command and a stop command from the outside of the gas turbine plant, and the like.

  The stop condition determination unit 102 determines whether or not a predetermined stop condition is satisfied. This stop condition is a condition for stopping the gas turbine 10. As the stop condition, the input unit 101 receives a stop command, the amplitude of vibration detected by the vibration meter 81 is abnormally large, the temperature detected by the exhaust thermometer 83 is suddenly decreased, and the like. Therefore, when the input unit 101 receives a stop command, the stop condition determination unit 102, when the amplitude of vibration detected by the vibrometer 81 becomes abnormally large, or when the temperature detected by the exhaust thermometer 83 suddenly decreases It is determined that the stop condition is satisfied. Here, the case where the temperature detected by the exhaust thermometer 83 rapidly decreases indicates a case where misfire occurs in the combustor 40.

  The fuel control unit 103 controls the opening degree of the fuel flow rate adjustment valve 42. The fuel control unit 103 determines the fuel flow rate so that a gas turbine output corresponding to a load indicated by an external load command is obtained. The fuel control unit 103 determines the opening degree of the fuel flow rate adjustment valve 42 at which this fuel flow rate is obtained, and sends a signal indicating this opening degree to the fuel flow rate adjustment valve 42.

  The intake air amount control unit 104 controls the intake air amount adjuster 30 so that the intake air amount of the air sucked by the compressor 20 becomes a target intake air amount corresponding to the state of the gas turbine 10. The intake air amount control unit 104 includes an IGV control unit 105 a that controls driving of the IGV device 31. The IGV control unit 105a includes a normal intake air amount control unit 106a and a stop transition control unit 107a. The normal intake air amount control unit 106a controls driving of the IGV device 31 when the stop condition is not satisfied. The normal intake air amount control unit 106a determines the IGV opening corresponding to the fuel flow rate determined by the fuel control unit 103, using a function G that defines the relationship between the fuel flow rate and the IGV opening.

  Here, the function G will be described with reference to FIG.

IGV opening θ, the characteristic opening is the maximum load operation opening θ (L) max (maximum load operation state) and minimum load operation opening θ (L) min (minimum load operation) State), opening degree θ (N) during no-load operation, and opening degree θ (S) when gas turbine is stopped (state when gas turbine is stopped). The maximum load operation opening degree θ (L) max is the IGV opening degree θ when the maximum load is applied to the gas turbine 10. The minimum load operation opening degree θ (L) min is the IGV opening degree θ when the gas turbine 10 is under the minimum load. The no-load operation opening degree θ (N) is the IGV opening degree θ when the gas turbine 10 is not loaded. The opening degree θ (S) when the gas turbine is stopped is the IGV opening degree θ when the gas turbine 10 is stopped. Note that the load on the gas turbine 10 means that the circuit breaker 63 is closed and the power generated by the generator 60 is supplied to the external power system 65 via the power line 62. Further, the no-load operation means that the circuit breaker 63 is open, in other words, the load is cut off, the power is not supplied from the generator 60 to the external power system 65, and the gas turbine 10 is driven. It is in a state. The characteristic magnitude relationship of the opening degree described above is as follows.
θ (L) max> θ (L) min> θ (N)> θ (S)

  Therefore, the opening degree θ (N) during no-load operation is an opening degree at which the intake air amount can be made larger than the opening degree θ (S) when the gas turbine is stopped. Further, the minimum load operation opening degree θ (L) min is an opening degree at which the intake air amount can be made larger than the no-load operation opening degree θ (N). The maximum load operation opening degree θ (L) max is an opening degree at which the intake air amount can be made larger than the minimum load operation opening degree θ (L) min.

In this function G, when the fuel flow rate F is 0, the gas turbine stop opening degree θ (S), which is the minimum IGV opening degree, is shown as the IGV opening degree θ. In this function G, when the fuel flow rate F is the no-load operation flow rate F (N), the no-load operation opening angle θ (N) is shown as the IGV opening degree θ. In this function G, when the fuel flow rate F is the minimum load operation flow rate F (L) min, the minimum load operation opening θ (L) min is shown as the IGV opening θ. In this function G, when the fuel flow rate F is, for example, a rated load operation flow rate F (L) r and a maximum load operation flow rate F (L) max, the maximum load operation opening degree θ (L) max is indicated. . In addition, the magnitude relationship of each flow volume demonstrated above is as follows.
0 <F (N) <F (L) min <F (L) r <F (L) max

  In this function G, the IGV opening θ is a constant no-load operation opening θ (N) in a range where the fuel flow rate F is greater than 0 and less than or equal to the no-load operation flow rate F (N). In this function, when the fuel flow rate F is greater than the no-load operation flow rate F (N) and less than or equal to the rated load operation flow rate F (L) r, the IGV opening θ increases as the fuel flow rate increases. In this function, when the fuel flow rate F is larger than the rated load operation flow rate F (L) r and less than the maximum load operation flow rate F (L) max, the IGV opening θ is constant and the maximum load operation opening θ ( L) max.

  The stop transition control unit 107a controls driving of the IGV device 31 when the stop condition is satisfied. The operation of the stop transition control unit 107a will be described in detail later using the flowchart shown in FIG.

  Next, the operation of the control device 100 will be described.

  As described above, the fuel control unit 103 of the control device 100 determines the fuel flow rate according to the load indicated by the external load command. The fuel control unit 103 determines the opening degree of the fuel flow rate adjustment valve 42 at which the fuel flow rate is obtained, and sends a signal indicating the opening degree to the fuel flow rate adjustment valve 42. As a result, the opening degree of the fuel flow rate adjusting valve 42 becomes the opening degree instructed by the fuel control unit 103, and the fuel flow rate supplied to the combustor 40 becomes the fuel flow rate corresponding to the load indicated by the load command.

  When the stop condition determination unit 102 determines that the stop condition is satisfied, the fuel control unit 103 sends a signal indicating the opening degree 0 to the fuel flow rate adjustment valve 42. As a result, the opening of the combustion flow rate control valve becomes zero, and the fuel flow rate supplied to the combustor 40 becomes zero. That is, when the input unit 101 receives a stop command, when the amplitude of vibration detected by the vibrometer 81 becomes abnormally large, or when the temperature detected by the thermometer suddenly decreases, the supply is supplied to the combustor 40. The fuel flow rate becomes zero.

  The normal intake air amount control unit 106a of the intake air amount control unit 104 is in operation unless the stop condition determining unit 102 determines that the stop condition is satisfied during operation of the gas turbine 10, as shown in the flowchart of FIG. The intake air amount adjuster 30 is controlled so as to achieve a target intake air amount according to the operating state of the gas turbine 10 (S1: normal intake air amount control step). The normal intake air amount control unit 106 a receives the fuel flow rate determined by the fuel control unit 103. The normal intake air amount control unit 106a determines the IGV opening degree according to the fuel flow rate from the fuel control unit 103 using the function G described with reference to FIG. Then, the normal intake air amount control unit 106 a sends the IGV opening to the IGV device 31. As a result, the IGV opening becomes an opening at which a target intake air amount corresponding to the fuel flow rate is obtained.

  When the gas turbine 10 is in the operating state, the stop condition determination unit 102 always determines whether or not the stop condition is satisfied (S2). When the stop condition is not satisfied, the normal intake air amount control step (S1) is continued. On the other hand, when the stop condition is satisfied, the stop transition control unit 107a executes the stop transition control step (S3).

  In the stop transition control step (S3), the stop transition control unit 107a performs a first intake amount reduction step (S4), an intake amount retention condition determination step (S5), an intake amount retention step (S6), and a release condition determination step (S7). ), The second intake air amount decreasing step (S8) is executed.

  When the stop condition is satisfied, the stop transition control unit 107a drives the IGV device 31 so that the intake air amount decreases (S4: first intake air amount decreasing step). That is, the stop transition control unit 107a sends a signal indicating that the IGV opening degree is decreased to the IGV device 31. As a result, the IGV opening becomes smaller than the current IGV opening, and the intake air amount decreases. When the gas turbine 10 is in an operating state, the IGV opening is equal to or greater than the opening θ (N) during no-load operation. For this reason, when the stop condition is satisfied, the IGV opening is equal to or larger than the no-load operation opening θ (N).

  Next, the stop transition control unit 107a determines whether or not a predetermined intake air amount holding condition is satisfied during the execution of the first intake air amount decreasing step (S4) (S5: intake air amount holding condition determining step). . When the stop transition control unit 107a determines that the intake amount holding condition is satisfied, the stop transition control unit 107a sends a signal indicating the drive stop to the IGV device 31. As a result, the IGV device 31 stops (S6: intake air amount holding step). Here, the intake amount holding condition is that the IGV opening is the no-load operation opening θ (N). Therefore, during this intake amount holding step (S6), the IGV opening is maintained at the no-load operation opening θ (N). For this reason, in the first intake air amount reduction step (S4), the IGV opening is reduced from the current IGV opening until the opening θ (N) during no-load operation.

  Next, the stop transition control unit 107a determines whether or not a predetermined release condition is satisfied during execution of the intake air amount holding step (S6) (S7: release condition determination step). When the stop transition control unit 107a determines that the release condition is satisfied, the stop transition control unit 107a drives the IGV device 31 so that the intake air amount decreases until the IGV opening becomes the gas turbine stop opening θ (S) (S8). : Second flow rate reduction step). That is, when the stop transition control unit 107a determines that the release condition is satisfied, the stop transition control unit 107a sends a signal indicating that the IGV opening is reduced to the IGV device 31, and the IGV opening is set to the gas turbine stop opening θ (S). Then, a signal indicating drive stop is sent to the IGV device 31. Here, the release condition is that the rotational speed of the compressor rotor 21 is lower than the rated rotational speed Nr of the compressor 20 by a rotational speed corresponding to 2% of the rated rotational speed Nr (= Nr × 0.02). Is the release rotational speed (= Nr−Nr × 0.02).

  When the power frequency of the external power system 65 is, for example, 60 Hz, the rotation speed of the generator rotor 61 and the gas turbine rotor 11 is 3600 rpm while the gas turbine 10 is under load operation. For this reason, in this case, the rated rotational speeds of the generator 60 and the gas turbine 10 are 3600 rpm. The gas turbine rotor 11 basically rotates at this rated rotational speed even during no-load operation. When the power frequency of the external power system 65 is 60 Hz, for example, the above-described release rotational speed is 3528 (= 3600-3600 × 0.02) rpm. Here, the release rotation speed is (Nr−Nr × 0.02). However, it is preferable that the release rotational speed is appropriately changed within the range of (Nr−Nr × (0.015 to 0.08)) depending on the model of the compressor 20 and the turbine 50 and the like.

  Therefore, when the rotational speed detected by the rotational speed meter 80 becomes the release rotational speed (= Nr−Nr × 0.02) during the execution of the intake air amount holding step (S6), the IGV opening is the opening during no-load operation. The opening degree θ (S) when the gas turbine is stopped is changed from θ (N), and then the opening degree θ (S) when the gas turbine is stopped is maintained.

  The stop transition control step (S3) is thus completed.

  Next, a specific change in the operating point specified by a specific change in the IGV opening, a corrected intake air amount, and a pressure ratio accompanying a change in the operating state of the gas turbine 10 will be described.

  First, the change in the IGV opening when the operation state of the gas turbine 10 changes from the maximum load operation state to the no load operation state will be described with reference to FIG.

  When the operation state of the gas turbine 10 is the maximum load operation state, as shown in FIG. 5, the IGV opening is the maximum load operation opening θ (L) max. In this state, when the input unit 101 receives a no-load operation command at time t = 0, or when the input unit 101 receives a load command indicating no load from the outside, the fuel flow rate is By the control of the fuel flow rate control valve 42 by the control unit 103, the flow rate F (L) max during the maximum load operation reaches the flow rate F (N) during the no load operation through the flow rate F (L) min during the minimum load operation. Further, the IGV opening is controlled by the control of the IGV device 31 by the normal intake air amount control unit 106a from the maximum load operation opening θ (L) max to the minimum load operation opening θ (L) min, It reaches the opening degree θ (N) during operation. As a result, the operation state of the gas turbine 10 becomes a no-load operation state.

  When the operation state of the gas turbine 10 changes from the maximum load operation state to the no load operation state, when the IGV opening is the minimum load operation opening θ (L) min (= the fuel flow is the minimum load operation flow F When (L) min), the load shedding LR is executed. That is, in this process, the circuit breaker 63 is opened, and the electrical connection between the external power system 65 and the generator 60 is broken.

  In the above series of processes, the rotational speed of the gas turbine rotor 11 is substantially constant at the rated rotational speed. However, at the time of load shedding LR, the rotational speed of the gas turbine rotor 11 slightly changes.

  Here, it is assumed that after the load shedding LR, the combustor 40 misfires before the operation state of the gas turbine 10 reaches the no-load operation state. In this case, the temperature detected by the exhaust thermometer 83 rapidly decreases. For this reason, the stop condition determining unit 102 determines that the stop condition is satisfied. In the present embodiment, when the stop condition is satisfied, the fuel control unit 103 sends a signal indicating the opening degree 0 to the fuel flow rate adjustment valve 42 as described above. For this reason, the fuel flow rate supplied to the combustor 40 becomes zero. In the present embodiment, when the stop condition is satisfied, the IGV opening is controlled by the stop transition control unit 107a as described above.

  After the load shedding LR, after the fuel is no longer burned in the combustor 40, the gas turbine rotor 11 and the generator rotor 61 connected thereto rotate with inertial force. The gas turbine rotor 11 and the generator rotor 61 connected thereto receive a resistance such as air and a frictional resistance from the bearing. For this reason, after the load shut-off LR, after the fuel is no longer burned in the combustor 40, the rotation of the gas turbine rotor 11 and the generator rotor 61 connected to the gas turbine rotor 11 with time elapses. Will drop.

  Suppose that the IGV control unit 105a does not have the stop transition control unit 107a but has only the normal intake air amount control unit 106a. As described above, the normal intake air amount control unit 106a determines the IGV opening according to the fuel flow rate from the fuel control unit 103, using the function G described with reference to FIG. Therefore, when the fuel flow rate obtained by the fuel control unit 103 becomes 0, the normal intake air amount control unit 106a sets the IGV opening to the gas turbine stop-time opening θ (S). For this reason, when the stop condition is satisfied (ECs) after the load cutoff LR and before the operation state of the gas turbine 10 reaches the no-load operation state, as described above, the normal intake air amount control unit 106a opens the IGV. As shown by the two-dot chain line in FIG. 5, the degree immediately after the stop condition is satisfied (ECs) is immediately set to the opening degree θ (S) when the gas turbine is stopped. Thereafter, the IGV opening is maintained at this gas turbine stop opening θ (S). Therefore, when the stop condition is satisfied (ECs) in the process in which the operation state of the gas turbine 10 is changed from the maximum load operation state to the no load operation state, the IGV opening is the maximum load operation opening θ (L) max. From now on, the opening degree θ (S) is reached when the gas turbine is stopped.

  Next, changes in the operating point of the compressor 20 when the operating state of the gas turbine 10 changes from the maximum load operating state to the no load operating state will be described with reference to FIG.

  When the operation state of the gas turbine 10 is the maximum load operation state, the operation point of the compressor 20 is an operation point P (L) max in a region where the pressure ratio is smaller and the intake air amount is sufficiently larger than the surging line Ls. . In other words, at the operating point P (L) max of the compressor 20 during the maximum load operation, a surge margin that is a merge until reaching the surging is large.

  In this state, as described above, when the input unit 101 receives a no-load operation command, or when the input unit 101 receives a load command indicating no load from the outside, the IGV opening is the normal intake air amount. By the control of the IGV device 31 by the control unit 106a, the opening degree θ (L) max during the maximum load operation reaches the opening degree θ (N) during the no-load operation. As a result, the gas turbine 10 enters a no-load operation state. The operating point P (N) of the compressor 20 during the no-load operation is an operating point having a smaller pressure ratio and a smaller intake amount than the operating point of the compressor 20 during the maximum load operation. The operating point P (N) of the compressor 20 during no-load operation is also an operating point in a region where the pressure ratio is smaller and the intake amount is sufficiently larger than the surging line Ls.

  As described above, the load cutoff LR is executed in the process in which the operation state of the gas turbine 10 changes from the maximum load operation state to the no load operation state.

  Here, it is assumed that after the load shedding LR, the combustor 40 misfires before the operation state of the gas turbine 10 reaches the no-load operation state. In this case, as described above, the stop condition determination unit 102 determines that the stop condition is satisfied.

  Suppose that the IGV control unit 105a does not have the stop transition control unit 107a but has only the normal intake air amount control unit 106a. As described above with reference to FIG. 5, when the stop condition is satisfied (ECs) after the load cutoff LR and before the operation state of the gas turbine 10 reaches the no-load operation state, the normal intake air amount control unit 106 a The IGV opening is immediately changed from the IGV opening when the stop condition is satisfied (ECs) to the gas turbine stop opening θ (S).

  The operating point P (S) 0 of the compressor 20 at the time when the IGV opening becomes the opening degree θ (S) when the gas turbine is stopped has a smaller pressure ratio than the operating point of the compressor 20 during no-load operation. The operating point is a small intake amount. Thereafter, as described above, the IGV opening is maintained at the gas turbine stop opening θ (S). Even when the IGV opening is maintained, the compressed air in the intermediate casing 15 is gradually exhausted to the outside through the combustor 40 and the turbine 50. For this reason, even when the IGV opening is maintained, the discharge pressure of the compressor 20 gradually decreases. However, when the IGV opening is maintained, the rate of decrease in the discharge pressure of the compressor 20 is smaller than the rate of decrease in the corrected intake air amount associated with the decrease in the rotational speed of the compressor 20. Therefore, when the IGV opening is maintained at the gas turbine stop opening θ (S), the operating point of the compressor 20 is the compression when the IGV opening becomes the gas turbine stop opening θ (S). As shown by the two-dot chain line in FIG. 7, the operating point P (S) 0 of the machine 20 changes in a direction in which the pressure ratio decreases more than the corrected intake air amount decreases.

  By the way, the change responsiveness of the discharge pressure of the compressor 20 to the change of the IGV opening is low. This is because the capacity of the intermediate casing 15 into which the compressed air from the compressor 20 flows is large. For this reason, even if the corrected intake flow rate changes as the IGV opening changes, the discharge pressure of the compressor 20 changes with a delay. Therefore, when the IGV opening is changed to a smaller side, the rate of decrease of the pressure ratio is smaller than the rate of decrease of the corrected intake amount accompanying the change of the IGV opening. For this reason, the operating point in the process from the maximum load operation opening degree θ (L) max to the no-load operation opening degree θ (N) gradually approaches the surging line Ls. As a result, the operating point P (S) 0 of the compressor 20 when the IGV opening becomes the gas turbine stop opening θ (S) is an operating point with a very small surge margin.

  Therefore, when the IGV opening immediately becomes the opening degree θ (S) when the gas turbine is stopped from the opening degree θ (L) max at the maximum load operation, the IGV opening becomes the opening degree θ (S) when the gas turbine is stopped. At this point, surging may occur.

  Next, a change in the IGV opening degree in the present embodiment when the stop condition is satisfied in the process in which the operation state of the gas turbine 10 is changing from the maximum load operation state to the no load operation state will be described with reference to FIG. explain.

  The IGV opening changes similarly to the change in the IGV opening described with reference to FIG. 5 until the stop condition is satisfied.

  When the stop condition is satisfied, as described above with reference to FIG. 4, the main body that controls the IGV device 31 is changed from the normal intake air amount control unit 106a to the stop transition control unit 107a.

  When the stop condition is satisfied (ECs), the stop transition control unit 107a drives the IGV device 31 so that the intake air amount decreases as described above (S4: first intake air amount reduction step). That is, the stop transition control unit 107a decreases the IGV opening. The stop transition control unit 107a determines whether or not the intake air amount holding condition is satisfied (ECr) during the execution of the first intake air amount decreasing step (S4) (S5: intake air amount holding condition determining step). Specifically, the stop transition control unit 107a determines whether or not the IGV opening is the no-load operation opening θ (N). When the stop transition control unit 107a determines that the IGV opening has reached the opening θ (N) during no-load operation, it sends a signal indicating drive stop to the IGV device 31. As a result, the IGV device 31 stops (S6: intake air amount holding step).

  Therefore, as shown in FIG. 6, when the operation condition of the gas turbine 10 is changing from the maximum load operation state to the no load operation state, when the stop condition is satisfied (ECs), the IGV opening is immediately The opening degree θ (S) at the time of turbine stop is not reached, and the opening degree θ (N) at the time of no-load operation is maintained.

  The stop transition control unit 107a determines whether or not the release condition is satisfied (ECc) during the execution of the intake air amount holding step (S6) (S7: release condition determination step). Specifically, the stop transition control unit 107a determines whether or not the rotation speed of the compressor rotor 21 has reached the release rotation speed (= Nr−Nr × 0.02). When the stop transition control unit 107a determines that the release condition is satisfied (ECc), that is, the rotation speed of the compressor rotor 21 has reached the release rotation speed, the IGV opening is the opening θ when the gas turbine is stopped as described above. Until (S), the IGV device 31 is driven so that the intake air amount decreases (S8: second flow rate reduction step). That is, the stop transition control unit 107a reduces the IGV opening from the no-load operation opening θ (N) to the gas turbine stop opening θ (S), and then the gas turbine stop opening θ (S). ).

  Next, the change of the operating point of the compressor 20 in the present embodiment when the stop condition is satisfied in the process in which the operation state of the gas turbine 10 is changing from the maximum load operation state to the no load operation state will be described with reference to FIG. Will be described.

  When the stop condition is satisfied (ECs), the stop transition control unit 107a changes the IGV opening from the IGV opening at the time when the stop condition is satisfied (ECs) to the opening degree θ (N) during no load operation as described above. (S4: first intake air amount decreasing step). For this reason, the operating point of the compressor 20 changes in the same manner as the change of the operating point described with reference to FIG. 6 until the IGV opening becomes the no-load operation opening θ (N).

  When the IGV opening becomes the no-load operation opening θ (N), the stop transition control unit 107a maintains the IGV opening at the no-load operation opening θ (N) (S6: intake air amount holding step). .

  As described above, when the IGV opening is maintained, the operating point of the compressor 20 changes in a direction in which the decrease in the pressure ratio becomes larger than the decrease in the corrected intake air amount. Therefore, when the IGV opening is maintained at the no-load operation opening θ (N), the operating point of the compressor 20 is the point at which the IGV opening is the no-load operation opening θ (N). The operating point P (N) changes in a direction in which the pressure ratio decreases more than the corrected intake air amount decreases. That is, the operation point of the compressor 20 changes in a direction away from the surging line Ls by executing the intake air amount holding step (S5).

  When the release condition is satisfied (ECc), that is, when the rotation speed of the compressor rotor 21 reaches the release rotation speed, the stop transition control unit 107a decreases the IGV opening until the gas turbine stop opening θ (S) is reached. . (S8: Second flow rate reduction step). When the IGV opening decreases from the no-load operation opening θ (N) to the gas turbine stop opening θ (S), the operating point of the compressor 20 is the no-load operation opening θ (N ) And the operating point P (N) 1 when the rotational speed of the compressor rotor 21 becomes the release rotational speed, the same as when the IGV opening is reduced.

  If the IGV opening becomes the opening θ (S) when the gas turbine is stopped and is maintained at the opening θ (N) during no-load operation, the operating point of the compressor 20 is that when the IGV opening is when the gas turbine is stopped. The operating point P (S) 1 at the time when the opening degree θ (S) is reached changes in a direction away from the surging line Ls in the same manner as when the above-described IGV opening degree is maintained.

  As described above, in the present embodiment, the operating point margin for the surging line Ls even when the stop condition is satisfied in the process in which the operating state of the gas turbine 10 is changing from the maximum load operating state to the no load operating state. Since the IGV opening is temporarily maintained at the no-load operation opening θ (N) before becomes small, the operating point can be moved away from the surging line Ls. Therefore, in the present embodiment, the occurrence of surging can be suppressed even if the stop condition is satisfied in the process in which the operation state of the gas turbine 10 is changing from the maximum load operation state to the no load operation state.

  Even if the IGV opening is maintained at the IGV opening at the time when the stop condition is satisfied when the stop condition is satisfied while the operation state of the gas turbine 10 is changing from the maximum load operation state to the no-load operation state. The occurrence of surging can be suppressed. The IGV opening when the stop condition for the IGV opening is satisfied is larger than the opening θ (N) during no-load operation. For this reason, when the condition for stopping the IGV opening is satisfied, the flow rate of the air passing through the gas turbine 10 passes through the gas turbine 10 when the IGV opening is the no-load operation opening θ (N). More than air flow. On the other hand, in the present embodiment, the IGV opening is reduced from the IGV opening at the time when the stop condition is satisfied to the no-load operation opening θ (N), and then the no-load operation opening θ (N ). For this reason, the flow rate of the air which passes the gas turbine 10 is less than the case where the direction of this embodiment maintains the IGV opening at the IGV opening at the time of the stop condition being satisfied. In other words, in this embodiment, the amount of air that tends to flow in the gas turbine 10 due to the inertial rotation of the gas turbine rotor 11 is greater than when the IGV opening is maintained at the IGV opening when the stop condition is satisfied. The flow is forcibly suppressed. Therefore, in the present embodiment, it is possible to promote a decrease in the rotational speed of the gas turbine rotor 11 after the stop condition is satisfied, and the gas turbine 10 can be brought into a stop state in a short time.

  The case where the stop condition is satisfied in the process in which the operation state of the gas turbine 10 is changing from the maximum load operation state to the no load operation state has been described in detail above. However, in the present embodiment, as described with reference to the flowchart of FIG. 4, the IGV opening is not set even if the stop condition is satisfied during the maximum load operation or the stop condition is satisfied during the minimum load operation. After the load operation opening degree θ (N) is reduced, the no-load operation opening degree θ (N) is maintained. For this reason, in the present embodiment, it is possible to suppress the occurrence of surging in the compressor 20 regardless of the operation state of the gas turbine 10 and the stop condition, and the gas turbine 10 can be turned on in a short time. Can be stopped.

  In the present embodiment, the IGV opening is maintained at the no-load operation opening θ (N) in the intake air amount holding step (S6). The opening degree θ (N) during no-load operation is the same as the IGV opening degree when the gas turbine 10 is intentionally placed in the no-load operation state. For this reason, some of the various states in the gas turbine 10 in the intake air amount maintaining step (S6) coincide with some of the various states in the gas turbine 10 in the no-load operation state. For this reason, in this embodiment, the burden on the control device 100 and the operator in the intake air amount holding step (S6) can be reduced.

  Further, the method for stopping the gas turbine 10 when misfire has occurred in the combustor 40 has been described above. However, the stop condition of this embodiment includes not only the case where the above-described event occurs in the gas turbine 10, but also the case where the operator of the gas turbine plant inputs a stop command to the control device 100, or the gas turbine A case where the control device 100 receives a stop command from outside the plant is also included. Therefore, in this embodiment, even when the gas turbine 10 is stopped due to various events, the occurrence of surging in the compressor 20 can be suppressed and the gas turbine 10 can be stopped in a short time. it can.

"Second embodiment"
The gas turbine plant as the first embodiment will be described with reference to FIGS. 10 and 11.

  Similarly to the gas turbine plant of the first embodiment, the gas turbine plant of the present embodiment also includes a gas turbine 10a, a generator 60, and a control device 100a, as shown in FIG. Moreover, the gas turbine 10a of this embodiment is also provided with the compressor 20a, the combustor 40, and the turbine 50 similarly to the gas turbine 10 of 1st embodiment. The intake air amount adjuster 30a of the compressor 20a of the present embodiment includes an IGV device 31 like the intake air amount adjuster 30 of the first embodiment. However, the intake air amount adjuster 30a of the present embodiment further includes a plurality of variable stationary blade devices 35.

  The variable stationary blade device 35 is in an air flow path in the compressor casing 24 and includes a plurality of variable stationary blades (hereinafter referred to as VV: Variable Vane) and a blade driving mechanism 37 that displaces the plurality of VVs 36. . The plurality of VVs 36 are disposed between any of the plurality of blade rows 23. The plurality of VVs 36 are arranged in the circumferential direction Dc. The blade drive mechanism 37 rotates each VV 36 around the blade rotation axis of each of the plurality of VVs 36 extending in the radial direction Dr from the axis Ar, and changes the opening degree of each VV 36. That is, the VV device 35 has the same basic structure as the IGV device 31 except that the position of the blade in the axial direction Da is different from the position of the blade in the axial direction Da of the IGV device 31.

  In the present embodiment, among the plurality of VV devices 35, the plurality of VVs 36 of the first VV device 35 a includes the first moving blade row 23 a on the most upstream side of the plurality of moving blade rows 23 and the first moving blade row 23 a. It arrange | positions between the 2nd moving blade row | line | rows 23b adjacent to the axial downstream side Dad with respect to the moving blade example 23a. The plurality of VVs 36 of the second VV device 35b are arranged between the second moving blade row 23b and the third moving blade row 23c adjacent to the axial downstream side Dad with respect to the second moving blade example 23b. ing.

  Similar to the control device 100 of the first embodiment, the control device 100a of the present embodiment, as shown in FIG. 11, includes an input unit 101, a stop condition determination unit 102, a fuel control unit 103, and an intake air amount control unit 104a. And having. Similar to the intake air amount control unit 104 of the first embodiment, the intake air amount control unit 104a of the present embodiment includes an IGV control unit 105a. The intake air amount control unit 104a of the present embodiment further includes a VV control unit 105b.

  The IGV control unit 105a includes a normal intake air amount control unit 106a and a stop transition control unit 107a. The normal intake air amount control unit 106a of the IGV control unit 105a controls driving of the IGV device 31 when the stop condition is not satisfied. Similarly to the normal intake air amount control unit 106a of the first embodiment, the normal intake air amount control unit 106a of the IGV control unit 105a also uses the function that defines the relationship between the fuel flow rate and the IGV opening degree. The IGV opening corresponding to the determined fuel flow rate is determined. However, the function used by the normal intake air amount control unit 106a of the IGV control unit 105a is a function that defines the relationship between the fuel flow rate and the IGV opening degree on the assumption that the VV device 35 exists. For this reason, it is determined by a function used by the normal intake air amount control unit 106a of the IGV control unit 105a, for example, a no-load operation opening degree θ (N) and a function used by the normal intake air amount control unit 106a of the first embodiment. The actual opening degree IGV may differ from the determined no-load operation opening degree θ (N). The stop transition control unit 107a controls driving of the IGV device 31 when the stop condition is satisfied. The stop transition control unit 107a of the IGV control unit 105a operates in the same manner as the stop transition control unit 107a of the first embodiment.

  Similarly to the IGV control unit 105a, the VV control unit 105b also includes a normal intake air amount control unit 106b and a stop transition control unit 107b. The normal intake air amount control unit 106b of the VV control unit 105b controls driving of the VV device 35 when the stop condition is not satisfied. Similarly to the normal intake air amount control unit 106a of the first embodiment, the normal intake air amount control unit 106b of the VV control unit 105b also uses a function that defines the relationship between the fuel flow rate and the VV opening degree. A VV opening corresponding to the determined fuel flow rate is determined. However, the function used by the normal intake air amount control unit 106b of the VV control unit 105b is a function that defines the relationship between the fuel flow rate and the VV opening degree on the assumption that the IGV device 31 exists. The stop transition control unit 107b controls driving of the VV device 35 when the stop condition is satisfied. The stop transition control unit 107b of the VV control unit 105b operates in the same manner as the stop transition control unit 107a of the first embodiment.

  Next, the operation of the control device 100a of this embodiment will be described.

  The fuel control unit 103 of the control device 100a operates in the same manner as the fuel control unit 103 of the first embodiment. That is, the fuel control unit 103 also sets the fuel flow rate supplied to the combustor 40 to a fuel flow rate corresponding to the load indicated by the load command from the outside. The fuel control unit 103 also sets the flow rate of fuel supplied to the combustor 40 to zero when the stop condition is satisfied.

  Further, the IGV control unit 105a and the VV control unit 105b of the intake air amount control unit 104a operate in the same manner as the IGV control unit 105a of the first embodiment. That is, the normal intake air amount control unit 106a of the IGV control unit 105a and the normal intake air amount control unit 106b of the VV control unit 105b are operating in the gas turbine 10a during operation unless the stop condition is satisfied during operation of the gas turbine 10a. The intake air amount adjuster 30a is controlled so as to achieve the target intake air amount according to the operating state (S1: normal intake air amount control step). The normal intake air amount control unit 106 a of the IGV control unit 105 a determines the IGV opening degree corresponding to the fuel flow rate obtained by the fuel control unit 103, and sends this IGV opening degree to the IGV device 31. In addition, the normal intake air amount control unit 106 b of the VV control unit 105 b determines a VV opening degree according to the fuel flow rate obtained by the fuel control unit 103, and sends this VV opening degree to the VV device 35. Further, when the stop condition is satisfied, the stop transition control unit 107a of the IGV control unit 105a and the stop transition control unit 107b of the VV control unit 105b are similar to the stop transition control unit 107a of the first embodiment in the first intake air amount. A decrease step (S4), an intake air amount holding condition determining step (S5), an intake air amount holding step (S6), a release condition determining step (S7), and a second intake air amount decreasing step (S8) are executed.

  Therefore, also in this embodiment, when the gas turbine 10a is stopped, the occurrence of surging in the compressor 20a can be suppressed and the gas turbine 10a can be stopped in a short time, as in the first embodiment. can do.

  The drive timing and drive amount of the VV device 35 may correspond to the drive timing and drive amount of the IGV device 31, but may not correspond to the drive timing and drive amount of the IGV device 31. That is, the operation of the stop transition control unit 107b of the VV control unit 105b may be interlocked with the operation of the stop transition control unit 107a of the IGV control unit 105a as a result, but the operation of the stop transition control unit 107b of the VV control unit 105b is The operation of the stop transition control unit 107a of the IGV control unit 105a may not be interlocked. For example, when the intake air amount holding condition is satisfied, the stop transition control unit 107b of the VV control unit 105b maintains the VV opening at the no-load operation opening degree, and the stop transition control unit 107a of the IGV control unit 105a The degree is maintained at the opening degree θ (N) during no-load operation. However, when the intake air amount holding condition is satisfied, the VV opening and the IGV opening may not be set to the no-load operation opening when the intake air regulator 30a is in the no-load operation state as a whole. As described above, the stop transition control unit 107b of the VV control unit 105b and the stop transition control unit 107a of the IGV control unit 105a are integratedly managed, so that the operation of the stop transition control unit 107b of the VV control unit 105b and the IGV control are performed. The operation of the stop transition control unit 107a of the unit 105a may not be linked. If the operation of the stop transition control unit 107b of the VV control unit 105b and the operation of the stop transition control unit 107a of the IGV control unit 105a are not linked, the IGV opening to be maintained and the VV opening to be maintained are appropriately changed, Furthermore, by appropriately changing the maintenance timing of the IGV opening and the maintenance timing of the VV opening, it is possible to reduce the possibility of surging and to shorten the stop time of the gas turbine 10a.

"Third embodiment"
The gas turbine plant as the first embodiment will be described with reference to FIGS. 12 and 13.

  As shown in FIG. 12, the gas turbine plant of this embodiment is a plant in which a plurality of extraction mechanisms 70 are added to the gas turbine plant of the second embodiment. Each of the plurality of extraction mechanisms 70 is a mechanism for extracting air from the compressor casing 24 and exhausting it outside the compressor casing 24. The gas turbine plant of this embodiment includes a front stage bleed mechanism 70a, an intermediate stage bleed mechanism 70b, and a rear stage bleed mechanism 70c.

  Each of the bleed mechanisms 70 has a bleed line 71, a cooling air line 73 branched from the bleed line 71, a bleed valve 72 and a pressure gauge 75 provided in the bleed line 71, and a cooling air line 73. The cooling air valve 74 is provided.

  In the compressor casing 24, a front stage bleed port 28a is formed at a position corresponding to the stage (front stage) on the axial upstream side Dau. In the compressor casing 24, an intermediate stage bleed port 28b is formed at a position corresponding to an intermediate stage (intermediate stage) in the axial direction Da. In the compressor casing 24, a rear stage bleed port 28c is formed at a position corresponding to the stage (rear stage) on the downstream side of the axis Dad. A front bleed line 71a of the front bleed mechanism 70a is connected to the front bleed port 28a. An intermediate stage extraction line 71b of the intermediate stage extraction mechanism 70b is connected to the intermediate stage extraction port 28b. A rear bleed line 71c of the rear bleed mechanism 70c is connected to the rear bleed port 28c. Each of the extraction lines 71a, 71b, 71c is connected to an extraction exhaust port 58 of the turbine casing 54. The bleed air exhaust port 58 is located at the position downstream of the axial line Dad in the turbine casing 54 with respect to the final moving blade row 53 a of the turbine 50.

  The rear cooling air line 73a branches off from the front extraction air line 71a. The rear cooling air line 73a is connected to a position corresponding to a stage (rear stage) on the downstream side of the axis Dau in the turbine casing 54. The rear cooling air valve 74a is provided in the rear cooling air line 73a. Further, the front stage bleed valve 72a is provided in the front stage bleed line 71a and on the downstream side of the air flow with respect to the branch position of the rear stage cooling air line 73a. A pre-stage pressure gauge 75a for detecting the pressure in the pre-stage extraction line 71a is provided in the pre-stage extraction line 71a and upstream of the branch position of the post-stage cooling air line 73a. The intermediate stage cooling air line 73b branches from the intermediate stage extraction line 71b. The intermediate stage cooling air line 73b is connected to a position corresponding to an intermediate stage (intermediate stage) in the axial direction Da in the turbine casing 54. The intermediate stage cooling air valve 74b is provided in the intermediate stage cooling air line 73b. The intermediate stage bleed valve 72b is provided in the intermediate stage bleed line 71b and downstream of the branching position of the intermediate stage cooling air line 73b. An intermediate-stage pressure gauge 75b for detecting the pressure in the intermediate-stage extraction line 71b is provided in the intermediate-stage extraction line 71b and upstream of the branch position of the intermediate-stage cooling air line 73b. ing. The front-stage cooling air line 73c branches from the rear-stage extraction line 71c. This front-stage cooling air line 73c is connected to a position corresponding to the stage (front stage) on the axial upstream side Dau in the turbine casing 54. The front cooling air valve 74c is provided in the front cooling air line 73c. Further, the rear stage bleed valve 72c is provided in the rear stage bleed line 71c and on the downstream side of the air flow with respect to the branch position of the front stage cooling air line 73c. A post-stage pressure gauge 75c for detecting the pressure in the post-stage extraction line 71c is provided in the post-stage extraction line 71c and upstream of the branch position of the pre-stage cooling air line 73c.

  As shown in FIG. 13, the control device 100b according to the present embodiment is similar to the control device 100a according to the second embodiment. The input unit 101, the stop condition determination unit 102, the fuel control unit 103, and the intake air amount control unit 104a. And having. The control device 100b of the present embodiment further includes an extraction control unit 108. The extraction control unit 108 controls the operations of the rear stage cooling air valve 74a, the front stage extraction valve 72a, the intermediate stage cooling air valve 74b, the intermediate stage extraction valve 72b, the front stage cooling air valve 74c, and the rear stage extraction valve 72c. The extraction control unit 108 controls the operation of these valves according to the IGV opening, the VV opening, the rotation speed of the compressor 20a, and the like.

  Even after the stop condition is satisfied and the IGV opening or the VV opening becomes the opening during no-load operation, that is, after the intake air amount holding step (S6), depending on the configuration of the compressor 20a, the compressor casing 24 In some cases, the possibility of occurrence of surging may increase. In this embodiment, in such a case, the operations of the rear-stage cooling air valve 74a, the front-stage extraction valve 72a, the intermediate-stage cooling air valve 74b, the intermediate-stage extraction valve 72b, the front-stage cooling air valve 74c, and the rear-stage extraction valve 72c are controlled. To suppress the occurrence of surging.

  For example, during the intake air amount holding step (S6), when the IGV opening or the VV opening becomes the no-load operation opening, as shown in FIG. 12, the rear stage Sr or middle of the compressor 20a The possibility of surging may increase at the stage Sm. When the possibility of occurrence of surging increases in the rear stage Sr of the compressor 20a, in order to increase the flow rate of the air passing through the rear stage Sr, the rear stage cooling air valve 74a, the front stage extraction valve 72a, the intermediate stage cooling air valve 74b, All of the intermediate stage extraction valve 72b, the front stage cooling air valve 74c, and the rear stage extraction valve 72c are closed. Further, when the possibility of occurrence of surging increases in the intermediate stage Sm of the compressor 20a, in order to increase the flow rate of air passing through the intermediate stage Sm, the rear stage cooling air valve 74a, the front stage extraction valve 72a, the intermediate stage cooling air valve 74b, the intermediate stage extraction valve 72b, and the front stage cooling air valve 74c are closed, and the rear stage extraction valve 72c is opened (first extraction process). The pressure at the position where the bleed exhaust port 58 of the turbine casing 54 to which each bleed line 71 is connected is lower than the pressure at each position of the compressor casing 24 and the pressure inside the intermediate casing 15. For this reason, when the rear stage bleed valve 72c is opened, the air existing in the vicinity of the intermediate stage Sm in the compressor casing 24 is exhausted to the outside via the rear stage bleed line 71c. As a result, the flow rate in the vicinity of the intermediate stage Sm in the compressor casing 24 increases, and the occurrence of surging in the intermediate stage Sm can be suppressed.

  The extraction control unit 108 executes the first extraction step by receiving from the intake air amount control unit 104a that the stop condition is satisfied and that the intake air amount controller 30a is in the no-load operation state. In addition, when the release condition is satisfied, the extraction control unit 108 closes the rear extraction valve 72c. That is, when the release condition is satisfied, the extraction control unit 108 ends the first extraction process by closing the subsequent extraction valve 72c or the like.

  As described with reference to FIG. 3, as the rotational speed of the compressor decreases, the position of the intersection with the choke line Lc corresponding to the rotational speed on the surging line Ls is the side where the corrected intake air amount decreases. Shift to. That is, as the rotation speed of the compressor decreases, the pressure ratio and intake air amount at the operating point where surging can occur are reduced. For this reason, in a compressor for a gas turbine, the possibility of occurrence of surging may increase around the rotational speed of 40% to 60% of the rated rotational speed. In this case, surging occurs in the front stage Sf of the compressor. When the possibility of surging increases at the front stage Sf of the compressor 20a, in order to increase the flow rate of the air passing through the front stage Sf, the rear stage cooling air valve 74a, the intermediate stage cooling air valve 74b, and the intermediate stage extraction valve 72b. The front-stage cooling air valve 74c and the rear-stage extraction valve 72c are closed, and the front-stage extraction valve 72a is opened (second extraction process). Further, the intermediate stage bleed valve 72b is opened as necessary. As a result, the air existing in the vicinity of the front stage Sf in the compressor casing 24 is exhausted to the outside through the front stage extraction line 71a, and the occurrence of surging in the front stage Sf can be suppressed.

  The extraction control unit 108 receives the end of the second intake amount reduction step (S8) from the intake amount control unit 104a, and the detected rotation number is, for example, 60% to 40% of the rated rotation number. As a result, the second extraction process is executed. Further, the extraction control unit 108 closes the pre-stage extraction valve 72a when the number of rotations detected by the number of rotations is, for example, 30% of the rated number of rotations. That is, the extraction control unit 108 ends the second extraction process when the number of rotations detected by the number of rotations is, for example, 30% of the rated number of rotations.

  As described above, in the present embodiment, it is possible to suppress the occurrence of surging in a part of the compressor casing 24 after the intake air amount holding step (S6).

  In the present embodiment, the bleed valve 72 is opened / closed according to the rotational speed of the compressor 20a. However, the bleed valve 72 may be opened / closed according to the pressure of the corresponding bleed line 71. Moreover, the gas turbine plant of this embodiment is a plant which added the extraction mechanism 70 to the gas turbine plant of 2nd embodiment. However, the extraction mechanism 70 may be added to the gas turbine plant of the first embodiment, and the extraction mechanism 70 may be controlled in the same manner as described above.

"Modification"
In the intake air amount holding step (S6) of the above embodiment, the intake air amount adjusters 30 and 30a are maintained in the no-load operation state. However, in the intake air amount maintaining step, the intake air amount adjusters 30 and 30a may be maintained in a state between the no-load operation state and the minimum load operation state. In this case, although the occurrence of surging of the compressor can be suppressed, the time until the gas turbine rotor 11 is stopped is longer than that in the above embodiment. Therefore, in the intake air amount holding step, even when the intake air amount adjusters 30 and 30a are maintained in a state between the no-load operation state and the minimum load operation state, the no-load operation state and the minimum load operation are performed. It is preferable that the state is a state on the minimum load operation state side than an intermediate state between the hour state.

  In the above embodiment, the release condition is that the rotation speed of the compressor becomes the release rotation speed. However, the release condition may be that the discharge pressure detected by the discharge pressure gauge 82 becomes the release discharge pressure. In this case, an operating point with a large surge margin is determined from the corrected intake air amount determined by the IGV opening and the rotational speed of the compressor, and the discharge pressure determined from the pressure ratio at this operating point is set as the release discharge pressure.

10, 10a: Gas turbine 11: Gas turbine rotor 14: Gas turbine casing 15: Intermediate casing 20, 20a: Compressor 21: Compressor rotor 22: Rotor shaft 23: Rotor blade row 24: Compressor casing 25: Inlet 26 : Discharge port 27: Stator blade row 28a: Pre-stage bleed port 28b: Intermediate-stage bleed port 28c: Sub-stage bleed port 30, 30a: Intake air amount adjuster 31: Inlet guide wing device (IGV device)
32: Inlet guide vane (IGV)
33: Blade drive mechanism 35: Variable stationary blade device (VV device)
36: Variable vane (VV)
37: Blade drive mechanism 40: Combustor 41: Fuel line 42: Fuel flow rate adjustment valve 50: Turbine 51: Turbine rotor 52: Rotor shaft 53: Rotor blade row 54: Turbine casing 57: Stator blade row 58: Extraction exhaust port 60 : Generator 61: Generator rotor 62: Power line 63: Circuit breaker 64: Transformer 65: External power system 70: Extraction mechanism 70a: Pre-stage extraction mechanism 70b: Intermediate-stage extraction mechanism 70c: Sub-stage extraction mechanism 71: Extraction line 71a : Pre-stage extraction line 71b: Intermediate-stage extraction line 71c: Sub-stage extraction line 72: Extraction valve 72a: Pre-stage extraction valve 72b: Intermediate-stage extraction valve 72c: Sub-stage extraction valve 73: Cooling air line 73a: Sub-stage cooling air line 73b: Intermediate stage Cooling air line 73c: front stage cooling air line 74: cooling air valve 74a: rear stage cooling air valve 74b: intermediate stage cooling air valve 74c: front stage cooling Gas valve 75: Pressure gauge 75a: Pre-stage pressure gauge 75b: Intermediate-stage pressure gauge 75c: Rear-stage pressure gauge 80: Revolution meter 81: Vibrometer 82: Discharge pressure gauge 83: Exhaust thermometers 100, 100a, 100b: Controller 101: Input unit 102: Stop condition determining unit 103: Fuel control unit 104, 104a: Intake amount control unit 105a: IGV control unit 106a: Normal intake amount control unit 107a: Stop transition control unit 105b: VV control unit 106b: Normal intake amount control Unit 107b: stop transition control unit 108: bleed control unit Ar: axis Da: axial direction Dau: axis upstream Dad: axis downstream Dc: circumferential direction Dr: radial direction

Claims (19)

A compressor that compresses air; a combustor that generates fuel by burning fuel in the air compressed by the compressor; and a turbine that is driven by the combustion gas,
A compressor rotor in which the compressor rotates about an axis; a compressor casing that covers an outer peripheral side of the compressor rotor; and an intake air amount regulator that adjusts an intake air amount of air flowing into the compressor casing; In a method for stopping a gas turbine,
A normal intake air amount control step of driving the intake air amount regulator so that the intake air amount becomes a target intake air amount when a predetermined stop condition is not satisfied;
A first intake air amount reduction step of driving the intake air amount regulator so that the intake air amount decreases when the stop condition is satisfied;
An intake air amount holding step for stopping driving of the intake air amount regulator when a predetermined intake air amount holding condition is satisfied during execution of the first intake air amount decreasing step;
When a predetermined release condition is satisfied during execution of the intake air amount holding step, the intake air amount controller is driven so that the intake air amount decreases until the intake air amount adjuster enters a gas turbine stop state. A second intake air amount reduction step to be performed;
To stop the gas turbine. The method for stopping a gas turbine according to claim 1,
The intake air amount adjuster includes a maximum load operation state when a maximum load is applied to the gas turbine, a minimum load operation state when a minimum load is applied to the gas turbine, and a load on the gas turbine. A state at the time of no-load operation when it is not applied, a state when the gas turbine is stopped, and a state between these states,
The no-load operation state is a state in which the intake air amount can be made larger than the gas turbine stop state,
The minimum load operation state is a state in which the intake air amount can be made larger than the no-load operation state,
The maximum load operation state is a state in which the intake air amount can be made larger than the minimum load operation state,
The intake air amount holding condition is that the intake air amount controller is in the no-load operation state or a state between the no-load operation state and the minimum load operation state. ,
How to stop a gas turbine. The method for stopping a gas turbine according to claim 2,
The intake air amount holding condition is a state between the no-load operation state and the minimum load operation state when the intake air amount adjuster is in the no-load operation state and the minimum load operation state. It is to become a state on the state side during the minimum load operation than the intermediate state between
How to stop a gas turbine. In the gas turbine stop method according to any one of claims 1 to 3,
The release condition is that the rotational speed of the compressor rotor is lower than the rated rotational speed of the compressor by a rotational speed corresponding to a predetermined ratio with respect to the rated rotational speed.
How to stop a gas turbine. In the gas turbine stop method according to any one of claims 1 to 3,
The release condition is that the discharge pressure of the compressor is reduced to a predetermined release discharge pressure.
How to stop a gas turbine. In the gas turbine stop method according to any one of claims 1 to 5,
The compressor has a compressor rotor shaft that is long in an axial direction in which the axis extends around the axis, and a plurality of motions that are fixed to the compressor rotor shaft side by side in the axial direction. A cascade, and
In the compressor casing, an intake port is formed at an end on the upstream side of the axis that is one side in the axial direction, and a discharge port is formed at an end on the downstream side of the axis that is opposite to the upstream side of the axis,
The intake air amount adjuster has at least the inlet guide blade device among an inlet guide blade device and a variable stationary blade device,
The inlet guide vane device is disposed in the air flow path in the compressor casing, and is arranged on the upstream side of the first moving blade row on the most upstream side of the plurality of moving blade stages, An inlet guide vane attached to the compressor casing, and a blade drive mechanism for displacing the inlet guide vane,
The variable stationary blade device is disposed in any one of a plurality of blade rows in an air flow path in the compressor casing, and is attached to the compressor casing. A stationary blade, and a blade driving mechanism that displaces the stationary blade,
How to stop a gas turbine. The method for stopping a gas turbine according to claim 6, wherein
The intake air amount regulator has the inlet guide vane device and the variable stator vane device,
In the intake amount holding step, the driving state of the inlet guide vane device and the variable stator vane device is different.
How to stop a gas turbine. In the gas turbine stop method according to any one of claims 1 to 7,
An extraction mechanism for extracting air from the compressor casing and exhausting the air out of the compressor casing;
After the intake amount holding step, the extraction step of exhausting air from the compressor casing by the extraction mechanism is performed.
How to stop a gas turbine. In the gas turbine stop method according to any one of claims 1 to 7,
A plurality of extraction mechanisms for extracting air from the compressor casing and exhausting it out of the compressor casing;
The plurality of bleed mechanisms are different from each other in the axial direction in the bleed positions for extracting air from the compressor casing,
After the intake amount holding step, execute a bleed step of exhausting air from the compressor casing by any one of the bleed mechanisms.
In the extraction step, air is exhausted from the compressor casing by a subsequent extraction mechanism whose extraction position is the most downstream in the axial direction among the plurality of extraction mechanisms during the intake amount holding step. In the remaining bleed mechanisms, after performing the first bleed process that does not exhaust air from the compressor casing and the second intake air amount decrease process, among the multiple bleed mechanisms, among the multiple bleed mechanisms, A second extraction step in which air is exhausted from inside the compressor casing by a pre-stage air extraction mechanism whose upstream position is in the axial direction in the axial direction, and in the remaining extraction mechanisms, air is not exhausted from the compressor casing; including,
How to stop a gas turbine. A compressor for compressing air;
A combustor that generates a combustion gas by burning fuel in air compressed by the compressor;
A turbine driven by the combustion gas;
With
A compressor rotor in which the compressor rotates about an axis; a compressor casing that covers an outer peripheral side of the compressor rotor; and an intake air amount regulator that adjusts an intake air amount of air flowing into the compressor casing; Having
In a gas turbine control device,
A normal intake air amount control unit that drives the intake air amount regulator so that the intake air amount becomes a target intake air amount when a predetermined stop condition is not satisfied;
When the stop condition is satisfied, a stop transition control unit that drives the intake air amount controller according to the condition;
Have
The stop transition control unit is
A first intake air amount reduction step of driving the intake air amount regulator so that the intake air amount decreases when the stop condition is satisfied;
An intake air amount holding step for stopping driving of the intake air amount regulator when a predetermined intake air amount holding condition is satisfied during execution of the first intake air amount decreasing step;
When a predetermined release condition is satisfied during execution of the intake air amount holding step, the intake air amount controller is driven so that the intake air amount decreases until the intake air amount adjuster enters a gas turbine stop state. A second intake air amount reduction step to be performed;
Run the
Control device for gas turbine. A gas turbine,
A control device for controlling the gas turbine;
With
The gas turbine is
A compressor for compressing air;
A combustor that generates a combustion gas by burning fuel in air compressed by the compressor;
A turbine driven by the combustion gas;
With
The compressor includes a compressor rotor that rotates about an axis, a compressor casing that covers an outer peripheral side of the compressor rotor, and an intake air amount controller that adjusts an intake air amount of air flowing into the compressor casing; Have
The control device includes:
A normal intake air amount control unit that drives the intake air amount regulator so that the intake air amount becomes a target air intake air amount when a predetermined stop condition is not satisfied;
When the stop condition is satisfied, a stop transition control unit that drives the intake air amount controller according to the condition;
Have
The stop transition control unit is
A first intake air amount reduction step of driving the intake air amount regulator so that the intake air amount decreases when the stop condition is satisfied;
An intake air amount holding step for stopping driving of the intake air amount regulator when a predetermined intake air amount holding condition is satisfied during execution of the first intake air amount decreasing step;
When a predetermined release condition is satisfied during execution of the intake air amount holding step, the intake air amount controller is driven so that the intake air amount decreases until the intake air amount adjuster enters a gas turbine stop state. A second intake air amount reduction step to be performed;
Run the
Gas turbine plant. The gas turbine plant according to claim 11,
The intake air amount adjuster includes a maximum load operation state when a maximum load is applied to the gas turbine, a minimum load operation state when a minimum load is applied to the gas turbine, and a load on the gas turbine. A state at the time of no-load operation when it is not applied, a state when the gas turbine is stopped, and a state between these states,
The no-load operation state is a state in which the intake air amount can be made larger than the gas turbine stop state,
The minimum load operation state is a state in which the intake air amount can be made larger than the no-load operation state,
The maximum load operation state is a state in which the intake air amount can be made larger than the minimum load operation state,
The intake air amount holding condition is that the intake air regulator is in the no-load operation state or a state between the no-load operation state and the minimum load operation state.
Gas turbine plant. The gas turbine plant according to claim 12,
The intake air amount holding condition is a state between the no-load operation state and the minimum load operation state when the intake air amount adjuster is in the no-load operation state and the minimum load operation state. It is to become a state on the state side during the minimum load operation than the intermediate state between
Gas turbine plant. In the gas turbine plant according to any one of claims 11 to 13,
Comprising a rotation speed meter for detecting the rotation speed of the compressor rotor;
The release condition is that the rotation speed of the compressor rotor detected by the tachometer is lower than the rated speed of the compressor by a speed corresponding to a predetermined ratio with respect to the rated speed. Is,
Gas turbine plant. In the gas turbine plant according to any one of claims 11 to 13,
A discharge pressure gauge for detecting the discharge pressure of the compressor;
The release condition is that the discharge pressure detected by the discharge pressure gauge has decreased to a predetermined release discharge pressure.
Gas turbine plant. In the gas turbine plant according to any one of claims 11 to 15,
The compressor rotor includes a plurality of compressor rotor shafts that are long in the axial direction in which the axis extends around the axis, and a plurality of compressor rotors that are fixed to the compressor rotor shaft side by side in the axial direction. A moving blade row,
In the compressor casing, an intake port is formed at an end on the upstream side of the axis that is one side in the axial direction, and a discharge port is formed at an end on the downstream side of the axis that is opposite to the upstream side of the axis,
The intake air amount adjuster has at least the inlet guide blade device among an inlet guide blade device and a variable stationary blade device,
The inlet guide vane device is disposed in the air flow path in the compressor casing, and is arranged on the upstream side of the first moving blade row on the most upstream side of the plurality of moving blade rows. An inlet guide vane attached to the compressor casing, and a blade drive mechanism for displacing the inlet guide vane,
The variable stationary blade device is disposed in any one of a plurality of blade rows in an air flow path in the compressor casing, and is attached to the compressor casing. A stationary blade, and a blade driving mechanism that displaces the stationary blade,
Gas turbine plant. The gas turbine plant according to claim 16,
The intake air amount regulator has the inlet guide vane device and the variable stator vane device,
The stop transition control unit, in the intake air amount holding step, makes the drive state of the inlet guide blade device and the variable stationary blade device different.
Gas turbine plant. In the gas turbine plant according to any one of claims 11 to 17,
An extraction mechanism for extracting air from the compressor casing and exhausting the air out of the compressor casing;
The control device includes an extraction control unit that executes an extraction process of exhausting air from the compressor casing by the extraction mechanism after the intake amount holding process.
Gas turbine plant. In the gas turbine plant according to any one of claims 11 to 17,
A plurality of extraction mechanisms for extracting air from the compressor casing and exhausting it out of the compressor casing;
The plurality of bleed mechanisms are different from each other in the axial direction in the bleed positions for extracting air from the compressor casing,
The control device has an extraction control unit that executes an extraction process of exhausting air from the compressor casing by any one of the plurality of extraction mechanisms after the intake amount holding process,
In the extraction step, air is exhausted from the compressor casing by a subsequent extraction mechanism whose extraction position is the most downstream in the axial direction among the plurality of extraction mechanisms during the intake amount holding step. In the remaining bleed mechanisms, after performing the first bleed process that does not exhaust air from the compressor casing and the second intake air amount decrease process, among the multiple bleed mechanisms, among the multiple bleed mechanisms, A second extraction step in which air is exhausted from inside the compressor casing by a pre-stage air extraction mechanism whose upstream position is in the axial direction in the axial direction, and in the remaining extraction mechanisms, air is not exhausted from the compressor casing; including,
Gas turbine plant.

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