Gas turbine power plant, and operational method therefor

Abstract

To flexibly respond to fluctuations in output due to external demand and stabilize voltage, etc. of an external power system.SOLUTION: A gas turbine power plant comprises: a gas turbine; a gas turbine generator; an extraction line that enables extracting, as extraction air, some of compressed air generated from the gas turbine by the gas turbine's compressor; an auxiliary turbine that can be driven by the extraction air flowing through the extraction line; an extraction valve provided in the extraction line; an auxiliary generator that can generate power by driving the auxiliary turbine; a clutch that allows switching a connection state between the auxiliary turbine and the auxiliary generator; and a control device. The control device has an extraction controller that controls opening and closing of the extraction valve, and a clutch controller that causes the clutch to be in a transmission state when the extraction valve is open, and in a disconnected state when the extraction valve is closed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a gas turbine power plant including a gas turbine and a method of operating the same. [Background technology]

[0002] A gas turbine includes a compressor that compresses air, a combustor that burns fuel in the air compressed by the compressor to generate combustion gas, and a turbine that is driven by the combustion gas. The rotor of the gas turbine is connected to the rotor of a generator.

[0003] A gas turbine plant described in Patent Document 1 listed below includes a clutch that is provided between the gas turbine and the generator and changes the connection state between the gas turbine and the generator. In this gas turbine plant, when the gas turbine is not being driven, the clutch is disengaged and a phase-modifying operation is performed in which the generator is operated with no load. When the generator is operated in a phase-modifying operation, reactive power is supplied from the generator to an external power system, thereby stabilizing the voltage, etc., of the external power system. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-074156 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, the number of power generation facilities using renewable energy such as solar and wind power has been increasing. However, such power generation facilities using renewable energy have large fluctuations in the amount of power generated. Therefore, gas turbine power generation plants are required to flexibly respond to fluctuations in external output requirements in order to compensate for the fluctuations in the amount of power generated by power generation facilities using renewable energy.

[0006] Furthermore, as mentioned above, power generation facilities using renewable energy such as solar and wind power have large fluctuations in the amount of power generated, so they often have storage batteries to compensate for this.Since storage batteries cannot supply reactive power, the increase in the number of power generation facilities using renewable energy such as solar and wind power tends to impair the stability of the voltage of the external power grid.

[0007] Therefore, an object of the present disclosure is to provide a technology that can flexibly respond to fluctuations in externally required output and can stabilize the voltage, etc. of an external power system. [Means for solving the problem]

[0008] One aspect of a gas turbine power plant to achieve the above object is to the gas turbine generator connected to the gas turbine and capable of generating electricity by driving the turbine; a bleed line that allows part of the compressed air generated by the compressor to be bleed air and from the gas turbine; an auxiliary turbine connected to the bleed line and capable of driving the bleed air that has flowed through the bleed line; a bleed valve provided in the bleed line; a synchronous auxiliary generator connected to the auxiliary turbine and capable of generating electricity by driving the auxiliary turbine; a clutch that can change a connection state between the auxiliary turbine and the auxiliary generator between a transmission state in which driving force of the auxiliary turbine is transmitted to the auxiliary generator and a disconnection state in which driving force of the auxiliary turbine is not transmitted to the auxiliary generator; a main generation power line that electrically connects the gas turbine generator to an external electric power system; an auxiliary generation power line that electrically connects the auxiliary generator to the external electric power system; and a control device. The control device includes a bleed controller that controls opening and closing of the bleed valve, and a clutch controller that brings the clutch into the transmitted state when the bleed valve is open and brings the clutch into the disengaged state when the bleed valve is closed.

[0009] In this aspect, by opening the bleed valve, a portion of the compressed air can be bled outside the gas turbine as bleed air. Therefore, in this aspect, the flow rate of the compressed air flowing into the combustor can be made smaller than the minimum intake air flow rate of the gas turbine. In order to achieve stable combustion of the fuel, fuel is supplied to the combustor in accordance with the flow rate of the compressed air flowing into the combustor. Therefore, in this aspect, the flow rate of the combustion gas flowing from the combustor into the turbine can be made smaller while still achieving stable combustion of the fuel. As a result, in this aspect, even if the externally required output is smaller than the output corresponding to the minimum intake air flow rate of the gas turbine, this required output can be met.

[0010] In this aspect, when the bleed valve is open, bleed air from the gas turbine flows into the auxiliary turbine, driving the auxiliary turbine. At this time, the clutch is in a transmission state, and the auxiliary generator generates electricity by driving the auxiliary turbine. The auxiliary generator outputs both active power and reactive power. As described above, in this aspect, when the required output from the outside is smaller than the output corresponding to the minimum intake air flow rate of the gas turbine, stable combustion of the fuel is possible even if the fuel flow rate is set to a value corresponding to the required output. Furthermore, the total power (active power) from the gas turbine generator and the auxiliary generator is less than the power that can be generated with the energy of the fuel supplied to the combustor. Therefore, even if power from the auxiliary generator is supplied to an external power system in addition to the power from the gas turbine generator, the amount of power supplied from the entire plant to the external power system can be made smaller than the amount of power generated by the gas turbine at the minimum intake air flow rate.

[0011] In this embodiment, when the bleed valve is closed and bleed air from the gas turbine does not flow into the auxiliary turbine, the clutch is disengaged, the rotor of the auxiliary generator rotates freely, and the system enters a no-load operation state. As a result, reactive power is output from the auxiliary generator even when the bleed valve is closed.

[0012] Therefore, in this aspect, whether the bleed valve is open or closed, the rotor of the auxiliary generator rotates and reactive power is supplied from the auxiliary generator to the external power system. Therefore, in this aspect, the voltage of the external power system can be stabilized. Furthermore, in this aspect, the inertial force of the rotor of the auxiliary generator can stabilize the frequency of the external power system.

[0013] A method for operating a gas turbine power plant as one aspect for achieving the above object is applied to the following gas turbine power plant. This gas turbine power plant includes a gas turbine having a compressor capable of compressing air, a combustor capable of burning fuel in the compressed air compressed by the compressor to generate combustion gas, and a turbine capable of being driven by the combustion gas, and a gas turbine generator connected to the gas turbine, capable of generating electricity by driving the turbine and transmitting the electricity to an external power system. This gas turbine power plant operation method includes the following steps: a main power generation process in which the gas turbine is driven to cause the gas turbine generator to generate power; an extraction process in which, during the main power generation process, a portion of the compressed air generated by the compressor is extracted as bleed air to the outside of the gas turbine to reduce the flow rate of the compressed air flowing into the combustor; an auxiliary power generation process in which, during the extraction process, an auxiliary turbine is driven by the bleed air extracted to the outside of the gas turbine to drive a synchronous auxiliary generator to generate power by driving the auxiliary turbine; and a phase modifying process in which, during the main power generation process, when the extraction process is not being performed, the auxiliary generator is operated with no load.

[0014] In this aspect, similar to the gas turbine power plant of the first aspect, it is possible to flexibly respond to fluctuations in externally required output, and similar to the gas turbine power plant of the first aspect, it is possible to stabilize the voltage and frequency of the external power grid. [Effects of the Invention]

[0015] According to one aspect of the present disclosure, it is possible to flexibly respond to fluctuations in externally required output and to stabilize the voltage, etc. of an external power system. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a system diagram of a gas turbine power plant according to a first embodiment of the present disclosure. [Figure 2] 4 is a graph showing the relationship between the actual output and the IGV opening degree of the gas turbine power plant in the first embodiment according to the present disclosure. [Figure 3] 3 is a flowchart showing an operation of the gas turbine power plant in the first embodiment according to the present disclosure. [Figure 4] FIG. 2 is an explanatory diagram showing a change in actual main power due to a change in required output and changes in each device due to a change in required output in the first embodiment of the present disclosure. [Figure 5] FIG. 2 is an explanatory diagram showing a state of the gas turbine power plant in the first embodiment according to the present disclosure when the required output is equal to or less than the rated output and is greater than the extraction steam output. [Figure 6] FIG. 2 is an explanatory diagram illustrating a state of the gas turbine power plant in the first embodiment according to the present disclosure, in which the gas turbine power plant is performing a steam extraction process with a required output equal to or lower than the extraction pressure. [Figure 7] FIG. 2 is an explanatory diagram illustrating a state of the gas turbine power plant during a discharge process in the gas turbine power plant according to the first embodiment of the present disclosure. [Figure 8] FIG. 4 is a system diagram of a gas turbine power plant according to a second embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, various embodiments and modifications of the gas turbine power plant according to the present disclosure will be described with reference to the drawings.

[0018] "First embodiment of gas turbine power plant" Hereinafter, an embodiment of a gas turbine power plant according to the present disclosure will be described with reference to FIGS.

[0019] As shown in FIG. 1 , the gas turbine power plant in this embodiment includes a gas turbine 1, a waste heat utilization facility 20 that can utilize the heat of exhaust gas discharged from the gas turbine 1, a gas turbine generator 6 that can generate electricity by driving the gas turbine 1, an air extraction facility 30 that can extract part of the air inside the gas turbine 1 to the outside, an auxiliary power generation facility 40, a power system facility 50, and a control device 100.

[0020] The gas turbine 1 includes a compressor 10 capable of compressing air A, a combustor 15 capable of generating combustion gas by burning fuel F in the compressed air compressed by the compressor 10, a fuel valve, a turbine 16 capable of being driven by the high-temperature, high-pressure combustion gas, and an intermediate casing 3.

[0021] The compressor 10 has a compressor rotor 11 that rotates about a rotor axis Ar, a compressor casing 12 that covers the compressor rotor 11, and an intake air amount regulator 13. Here, the direction in which the rotor axis Ar extends is referred to as the axial direction Da, and one side of this axial direction Da is referred to as the axial upstream side Dau, and the other side is referred to as the axial downstream side Dad.

[0022] The compressor rotor 11 has a compressor rotor shaft 11s that extends in the axial direction Da centered on the rotor axis Ar, and a plurality of rotor blade rows 11b fixed to the compressor rotor shaft 11s. The plurality of rotor blade rows 11b are aligned in the axial direction Da. Each of the plurality of rotor blade rows 11b has a plurality of rotor blades aligned in the circumferential direction about the rotor axis Ar. The intake air amount regulator 13 has a plurality of inlet guide vanes (IGVs) 13v that are arranged inside the compressor casing 12 and on the axial upstream side Dau of the plurality of rotor blade rows 11b, and a driver 13d that can change the orientation of each inlet guide vane 13v.

[0023] The turbine 16 is disposed on the axial downstream side Dad of the compressor 10. The turbine 16 has a turbine rotor 17 that rotates about a rotor axis Ar by combustion gas from the combustor 15, and a turbine casing 18 that covers the turbine rotor 17.

[0024] The turbine rotor 17 has a turbine rotor shaft 17s that extends in the axial direction Da centered on the rotor axis Ar, and a plurality of rotor blade rows 17b fixed to the turbine rotor shaft 17s. The plurality of rotor blade rows 17b are aligned in the axial direction Da. Each of the plurality of rotor blade rows 17b has a plurality of rotor blades aligned in the circumferential direction with respect to the rotor axis Ar.

[0025] The turbine rotor 17 and the compressor rotor 11 are connected to each other so as to be rotatable together about the same rotor axis Ar, thereby forming a gas turbine rotor 2. To this gas turbine rotor 2, a rotor of a gas turbine generator 6 is connected.

[0026] The intermediate casing 3 is disposed between the compressor casing 12 and the turbine casing 18 in the axial direction Da, and connects the compressor casing 12 and the turbine casing 18. Compressed air discharged from the compressor 10 flows into the intermediate casing 3. The combustor 15 is fixed to the intermediate casing 3. A fuel line 4 is connected to the combustor 15. The fuel line 4 is provided with the aforementioned fuel valve that adjusts the flow rate of the fuel F flowing through the fuel line 4.

[0027] The waste heat utilization facility 20 includes a heat recovery boiler 21, a chimney 22, a steam turbine 23 that can be driven by steam from the heat recovery boiler 21, a main steam line 24 that can guide the steam generated in the heat recovery boiler 21 to the steam turbine 23, a condenser 25 that can convert the steam exhausted from the steam turbine 23 back into water, a feedwater line 26 that can guide the water in the condenser 25 to the heat recovery boiler 21, and a feedwater pump 27 provided in the feedwater line 26. A driven object that can be rotated by the rotation of the rotor is connected to the rotor of the steam turbine 23. Examples of the driven object include the rotor of the gas turbine generator 6, the rotor of a steam turbine generator independent of the gas turbine generator 6, and the impeller of a pump.

[0028] The heat recovery boiler 21 can generate steam by evaporating water using the heat of exhaust gas, which is combustion gas discharged from the turbine 16. The heat recovery boiler 21 has a duct 21d connected to the turbine casing 18 and a heat transfer tube 21t arranged in the duct 21d. Exhaust gas from the turbine 16 flows through the duct 21d. Liquid water or gaseous water flows through the heat transfer tube 21t. One end of the heat transfer tube 21t forms a water inlet and is connected to the water supply line 26. The other end of the heat transfer tube 21t forms a steam outlet and is connected to the main steam line 24. The chimney 22 is connected to the duct 21d of the heat recovery boiler 21.

[0029] The extraction equipment 30 includes an extraction line 31 that can extract part of the compressed air generated by the compressor 10 as extraction air from the gas turbine 1, an extraction valve 32, and an auxiliary turbine 33 that can be driven by the extraction air that has flowed through the extraction line 31.

[0030] The auxiliary turbine 33 has a rotatable auxiliary turbine rotor 34 and an auxiliary turbine casing 35 that covers the auxiliary turbine rotor 34. One end of the bleed line 31 is connected to the intermediate casing 3 of the gas turbine 1. The other end of the bleed line 31 is connected to the auxiliary turbine casing 35. Thus, part of the compressed air that has flowed into the intermediate casing 3 can flow into the auxiliary turbine casing 35 via the bleed line 31 as bleed air. The auxiliary turbine rotor 34 rotates by the bleed air that has flowed into the auxiliary turbine casing 35. A bleed valve 32 is provided in the bleed line 31. This bleed valve 32 can adjust the flow rate of the bleed air flowing through the bleed line 31.

[0031] The auxiliary power generating facility 40 includes a transmission 42 , a clutch 43 , an auxiliary generator 41 , and an electricity storage device 45 .

[0032] The transmission 42 has an input shaft 42i, an output shaft 42o, and a plurality of gears 42g provided between the input shaft 42i and the output shaft 42o. The input shaft 42i is connected to the auxiliary turbine rotor 34. The transmission 42 functions as a reducer that reduces the rotation speed of the auxiliary turbine rotor 34.

[0033] The clutch 43 has an input shaft 43i, an output shaft 43o, and a clutch mechanism 43m provided between the input shaft 43i and the output shaft 43o. The clutch mechanism 43m can change the connection state between the input shaft 43i and the output shaft 43o between a transmission state in which the driving force from the input shaft 43i is transmitted to the output shaft 43o and a disconnected state in which the driving force from the input shaft 43i is not transmitted to the output shaft 43o. The input shaft 43i of the clutch 43 is connected to the output shaft 42o of the transmission 42.

[0034] The auxiliary generator 41 includes a rotatable auxiliary generator rotor 41ra, a rotor 41rb attached to the auxiliary generator rotor 41ra, an auxiliary generator casing 41c that covers the auxiliary generator rotor 41ra and the rotor 41rb, a stator 41s provided inside the auxiliary generator casing 41c, and an inertial body 41i attached to the auxiliary generator rotor 41ra. The auxiliary generator rotor 41ra is connected to an output shaft 43o of a clutch 43. The clutch 43 can change the connection state between the auxiliary turbine 33 and the auxiliary generator 41 between a transmission state in which the driving force of the auxiliary turbine 33 is transmitted to the auxiliary generator 41 and a disconnection state in which the driving force of the auxiliary turbine 33 is not transmitted to the auxiliary generator 41. The rotor 41rb and the inertial body 41i are both attached to the auxiliary generator rotor 41ra so as to rotate integrally with the auxiliary generator rotor 41ra. The inertial body 41i may be any object that has weight and is balanced around the rotational axis of the auxiliary generator rotor 41ra. The inertial body 41i in this embodiment is a disk-shaped flywheel centered on the central axis of rotation of the auxiliary generator rotor 41ra.

[0035] In this embodiment, the auxiliary generator 41 and the gas turbine generator 6 are both synchronous generators.

[0036] The power storage device 45 has a storage battery 46 and an AC / DC converter 47. The AC / DC converter 47 can convert AC power from an external source into DC power and send it to the storage battery 46, and can also convert DC power from the storage battery 46 into AC power and send it to the outside.

[0037] The power system equipment 50 includes a GT generator dedicated power line 51g, an AT generator dedicated power line 51a, a BESS dedicated power line 51b, an in-plant shared power line 51p, an external connection power line 51c, multiple transformers 53a, 53b, 53c, and 53g, and multiple switches 54a, 54b, 54c, and 54g. The GT generator dedicated power line 51g is electrically connected at one end to the gas turbine generator 6 and at the other end to the in-plant shared power line 51p. The AT generator dedicated power line 51a is electrically connected at one end to the auxiliary generator 41 and at the other end to the in-plant shared power line 51p. The BESS dedicated power line 51b is electrically connected at one end to the power storage device 45 and at the other end to the in-plant shared power line 51p. The external connection power line 51c electrically connects the in-plant shared power line 51p to an external power system 60.

[0038] To compensate for fluctuations in the amount of power generated by power generation facilities that use renewable energy such as solar power and wind power, a power storage device 65 is connected to the external power system 60. Like the power storage device 45 provided in the plant in this embodiment, this power storage device 65 also includes a storage battery 66 and an AC / DC converter 67.

[0039] A transformer 53g and a switch 54g are provided on the GT generator-dedicated power line 51g. Furthermore, a power meter 55 is connected to the GT generator-dedicated power line 51g to detect the amount of power generated by the gas turbine generator 6, in other words, the actual output PWr of the gas turbine 1. A transformer 53a and a switch 54a are provided on the AT generator-dedicated power line 51a. A transformer 53b and a switch 54b are provided on the BESS-dedicated power line 51b. A transformer 53c and a switch 54c are also provided on the external connection power line 51c. Each of the switches 54a, 54b, 54c, and 54g has a first terminal, a second terminal, and a switching mechanism. The switching mechanism can change the connection state between the first terminal and the second terminal between an ON state in which the first terminal and the second terminal are electrically connected and an OFF state in which the first terminal and the second terminal are not electrically connected. Therefore, for example, the switch 54b provided on the BESS dedicated power line 51b can realize an ON state in which the external power system 60, the auxiliary generator 41, and the storage battery 46 are electrically connected, and an OFF state in which the external power system 60, the auxiliary generator 41, and the storage battery 46 are not electrically connected.

[0040] In this embodiment, the GT generator dedicated power line 51g, the in-plant shared power line 51p, and the external connection power line 51c constitute a main power generation power line 52m that electrically connects the gas turbine generator 6 to the external power system 60. The AT generator dedicated power line 51a, the in-plant shared power line 51p, and the external connection power line 51c constitute an auxiliary power generation power line 52a that electrically connects the auxiliary generator 41 to the external power system 60. In addition, the BESS dedicated power line 51b, the in-plant shared power line 51p, the external connection power line 51c, and the AT generator dedicated power line 51a constitute a storage battery power line 52b that electrically connects the power storage device 45 to the external power system 60 and the auxiliary generator 41.

[0041] The control device 100 includes a main controller 101, a fuel controller 102, an IGV controller 103, a bleed controller 104, an opening / closing controller 105, and a clutch controller 106.

[0042] The main controller 101 receives various instructions regarding the plant, including the required power PWc required of the gas turbine 1 from the outside, and the actual power PWr detected by the power meter 55, and controls the other controllers.

[0043] The fuel controller 102 receives the required power PWc and the actual power PWr from the main controller 101, determines the opening of the fuel valve according to the deviation between the required power PWc and the actual power PWr, and instructs the fuel valve to change the opening. A change in the flow rate of fuel supplied to the combustor 15 is positively correlated with a change in the opening of the fuel valve. Furthermore, a change in the opening of the fuel valve is positively correlated with a change in the required power PWc. Therefore, a change in the flow rate of fuel supplied to the combustor 15 is positively correlated with a change in the required power PWc. Therefore, as the required power PWc increases, the flow rate of fuel supplied to the combustor 15 increases, and as the required power PWc decreases, the flow rate of fuel supplied to the combustor 15 decreases.

[0044] The IGV controller 103 receives the actual output PWr from the main controller 101, determines the IGV opening θ according to this actual output PWr, and instructs the intake air regulator 13 of this IGV opening θ. As shown in FIG. 2, when the actual output PWr is between the intermediate output PWmid and the rated output PWrad, changes in the IGV opening θ have a positive correlation with changes in the actual output PWr. Therefore, as the actual output PWr increases, the IGV opening θ also increases, and as the actual output PWr decreases, the IGV opening θ also decreases. When the actual output PWr is the intermediate output PWmid, the IGV opening θ is at its minimum opening θmin, and when the actual output PWr is the rated output PWrad, the IGV opening θ is at its maximum opening θmax. Therefore, it can be said that the intermediate output PWmid is the maximum actual output PWr when the IGV opening θ is at its minimum opening θmin.

[0045] The bleed controller 104 receives the actual output PWr from the main controller 101 and commands the bleed valve 32 to open or close depending on whether or not this actual output PWr satisfies the bleed condition. Here, the bleed condition is that the actual output PWr detected by the power meter 55 is equal to or less than a predetermined bleed output PWbl. Here, the bleed output PWbl is a pressure less than the aforementioned intermediate output PWmid, as shown in FIG. 2. If the bleed controller 104 determines that the actual output PWr detected by the power meter 55 satisfies the bleed condition, in other words, that the actual output PWr is equal to or less than the bleed output PWbl, it commands the bleed valve 32 to open. On the other hand, if the bleed controller 104 determines that the actual output PWr detected by the power meter 55 does not satisfy the bleed condition, in other words, that the actual output PWr is greater than the bleed output PWbl, it commands the bleed valve 32 to close.

[0046] The switching controller 105 controls the switches 54a, 54b, 54c, and 54g. When an emergency that is inconvenient for the plant occurs, the switching controller 105 instructs the switches 54a, 54b, 54c, and 54g corresponding to the emergency to be turned off. Furthermore, the switching controller 105 instructs the switch 54b provided on the BESS-dedicated power line 51b to be turned on or off depending on whether the extraction valve 32 is open or closed and on the discharge conditions described below. The switching controller 105 instructs the switch 54b to be turned on when the discharge conditions are met and the extraction valve 32 is open. Furthermore, the switching controller 105 instructs the switch 54b to be turned off when the discharge conditions are not met and the extraction valve 32 is not open.

[0047] The clutch controller 106 controls the clutch 43. The clutch controller 106 puts the clutch 43 into a transmission state when the bleed valve 32 is open, and puts the clutch 43 into a disengaged state when the bleed valve 32 is closed.

[0048] Next, the operation of the gas turbine power plant will be described with reference to the flowchart shown in FIG.

[0049] First, the main controller 101 determines whether to execute main power generation, which involves driving the gas turbine 1 and causing the gas turbine generator 6 to generate electricity (main power generation execution determination step S1). When the main controller 101 determines to execute main power generation, it instructs the fuel controller 102 and the IGV controller 103 to execute the main power generation step S2.

[0050] This main power generation process S2 includes a fuel control process S2a in which the fuel controller 102 controls the fuel flow rate, and an IGV control process S2b in which the IGV controller 103 controls the intake air flow rate of the gas turbine 1.

[0051] In the fuel control process S2a, the fuel controller 102 receives the required output PWc from the outside and the actual output PWr detected by the power meter 55. The fuel controller 102 determines the opening degree of the fuel valve according to the deviation between the required output PWc and the actual output PWr, and instructs the fuel valve to set this opening degree. Therefore, as described above, the flow rate of fuel supplied to the combustor 15 basically has a value that has a positive correlation with the required output PWc. When the required output PWc is equal to or less than the rated output PWrad, fuel commensurate with the required output PWc is supplied to the combustor 15. However, when the required output PWc is greater than the rated output PWrad, fuel commensurate with the required output PWc is not supplied to the combustor 15, but fuel commensurate with the rated output PWrad is supplied to the combustor 15, from the viewpoint of protecting the combustor 15 and the turbine 16. Therefore, the output of the gas turbine 1 basically does not exceed the rated output PWrad.

[0052] In the IGV control step S2b, the IGV controller 103 receives the actual output PWr detected by the power meter 55. The IGV controller 103 determines the IGV opening θ according to the actual output PWr and notifies the intake air regulator 13 of the IGV opening θ (IGV control step S2b). In this case, as described above with reference to FIG. 2, the IGV opening θ assumes a value that has a positive correlation with the actual output PWr. However, when the actual output PWr is equal to or less than the intermediate output PWmid, the IGV opening θ is maintained at the minimum opening θmin, and when the actual output PWr is equal to the rated output PWrad, the IGV opening θ is maintained at the maximum opening θmax. Therefore, when the actual output PWr is equal to or less than the intermediate output PWmid, the intake air flow rate of the gas turbine 1 is maintained at the minimum flow rate, and when the actual output PWr is equal to the rated output PWrad, the intake air flow rate of the gas turbine 1 is maintained at the maximum flow rate.

[0053] By executing the fuel control process S2a and the IGV control process S2b described above, the gas turbine 1 is driven and the gas turbine generator 6 generates electricity.

[0054] If the required output PWc from the outside is equal to or less than the rated output PWrad and greater than the extraction output PWbl, as shown in FIGS. 4 and 5 , the extraction valve 32 is closed, the clutch 43 is disengaged, and the switch 54b on the BESS-dedicated power line 51b is off. In this case, the gas turbine generator 6 outputs active power PWac according to the required output PWc and also outputs reactive power PWrac. Furthermore, because the extraction valve 32 is closed, compressed air in the intermediate casing 3 is not supplied to the auxiliary turbine 33 via the extraction line 31, and the auxiliary turbine 33 is not driven. Therefore, the auxiliary generator 41 enters a no-load operation state, and does not output active power PWac to the outside, but only reactive power PWrac (phase modifying step S3). At this time, the auxiliary generator 41 receives a small amount of active power PWac from the outside to counteract the frictional force generated by the rotation of the auxiliary generator rotor 41ra. Furthermore, since the switch 54b provided on the BESS dedicated power line 51b is in the OFF state, no power is input or output to or from the power storage device 45. In other words, the power storage device 45 is not charged with power, and the power storage device 45 is not discharged.

[0055] Therefore, in this case, the plant supplies to the external power system 60 active power PWac that is substantially the same as the active power PWac output by the gas turbine generator 6. In addition, the plant supplies to the external power system 60 reactive power PWrac output by the gas turbine generator 6 and reactive power PWrac output by the auxiliary generator 41.

[0056] The bleed controller 104 determines whether or not the bleed condition for bleeding part of the compressed air in the intermediate casing 3 as bleed air is satisfied (bleed condition determination step S4). As described above, this bleed condition is that the actual output PWr detected by the power meter 55 is equal to or less than the bleed output PWbl. When the bleed controller 104 determines that the bleed condition is satisfied, it instructs the bleed valve 32 to open. As a result, as shown in Figures 4 and 6, the bleed valve 32 opens, and part of the compressed air in the intermediate casing 3 is supplied as bleed air to the auxiliary turbine 33 via the bleed line 31 (bleed step S5). The auxiliary turbine 33 starts to operate due to the inflow of this bleed air.

[0057] As a result of the opening of the bleed valve 32, the clutch controller 106 instructs the clutch 43 to enter a transmission state. As a result, the driving force of the auxiliary turbine 33 is transmitted to the auxiliary generator 41, and the auxiliary generator 41 starts generating power (auxiliary power generation step S6). On the other hand, as the auxiliary generator 41 enters load operation, the phase modifying step S3 is stopped (phase modifying stop step S7).

[0058] Since the bleed valve 32 is opened, the on / off controller 105 instructs the switch 54b provided on the BESS dedicated power line 51b to be turned on. As a result, the switch 54b is turned on, and the power generated by the auxiliary generator 41 is charged to the power storage device 45 (charging step S8).

[0059] It is assumed that the extraction stroke S5 is not executed even when the actual output PWr is equal to or less than the extraction output PWbl. In this case, the flow rate of fuel supplied to the combustor 15 has a value that is positively correlated with the required output PWc, while the flow rate of air drawn into the compressor 10 is maintained at the flow rate when the actual output PWr is the intermediate output PWmid. Therefore, the fuel-air ratio, which is the ratio of the fuel flow rate to the air flow rate in the combustor 15, is smaller than when the actual output PWr is the intermediate output PWmid. When the fuel-air ratio decreases, the temperature of the combustion gas flowing from the combustor 15 into the turbine 16 decreases, and the temperature of the steam generated in the heat recovery boiler 21 decreases. As a result, the output efficiency of the waste heat utilization equipment 20 decreases. Furthermore, when the fuel-air ratio decreases, the combustibility of the fuel deteriorates, and in the worst case, a misfire may occur.

[0060] 4 and 6, when the required output PWc becomes equal to or less than the extraction output PWbl, the extraction valve 32 opens, part of the compressed air in the intermediate casing 3 is extracted as extraction air, and the extraction process S5 is performed. As a result, the flow rate of the compressed air flowing into the combustor 15 becomes less than the minimum intake flow rate of the gas turbine 1, and fuel corresponding to the required output PWc is supplied to the combustor 15, thereby enabling stable combustion of the fuel. That is, in this embodiment, the actual output PWr of the gas turbine 1 can be made equal to or less than the extraction output PWbl that is less than the intermediate output PWmid while maintaining stable operation of the gas turbine 1. At this time, the gas turbine generator 6 outputs active power PWac corresponding to the required output PWc, and also outputs reactive power PWrac.

[0061] Furthermore, when the required output PWc becomes equal to or less than the extraction steam output PWbl, the extraction air flows into the auxiliary turbine 33, driving the auxiliary turbine 33. Furthermore, the clutch 43 enters a transmission state, the driving force of the auxiliary turbine 33 is transmitted to the auxiliary generator 41, and an auxiliary power generating step S6 is executed. As a result, the auxiliary generator 41 outputs an auxiliary output (auxiliary power) PWra. Meanwhile, the auxiliary generator 41 enters load operation, and the phase modifying step S3 is stopped. However, even if the phase modifying step S3 is stopped, the auxiliary generator 41 outputs reactive power PWrac together with active power PWac as the auxiliary output (auxiliary power) PWra.

[0062] When the required output PWc becomes equal to or less than the extracted steam output PWbl, the switch 54b provided on the BESS dedicated power line 51b is turned on, and the auxiliary output (auxiliary power) PWra, which is the active power PWac generated by the auxiliary generator 41, is charged into the power storage device 45. In addition, the reactive power PWrac from the auxiliary generator 41 is supplied to the external power system 60 together with the reactive power PWrac from the gas turbine generator 6.

[0063] If the bleed controller 104 determines in the bleed condition determination step S4 that the bleed conditions are not satisfied, the bleed controller 104 instructs the bleed valve 32 to close. As a result of this instruction, if the bleed valve 32 is open, it is closed, and if the bleed valve 32 is closed, it is maintained closed (bleed stop step S9).

[0064] Furthermore, if the extraction controller 104 determines in the extraction condition determination step S4 that the extraction condition is not satisfied, the switching controller 105 determines whether or not the discharge condition is satisfied (discharge condition determination step S10). Here, the discharge condition means that the required output PWc is equal to or greater than a discharge output PWdis that is greater than the rated output PWrad of the gas turbine 1, and that the amount of change in the required output PWc per unit time is greater than a predetermined value. If the switching controller 105 determines that the discharge condition is satisfied, it instructs the switch 54b provided on the BESS dedicated power line 51b to be turned on. As a result, the switch 54b is turned on, and the power stored in the power storage device 45 is discharged (discharge step S11).

[0065] When the discharge condition is satisfied, the process is repeated, as shown in FIGS. 4 and 7, the bleed valve 32 is closed, the output of the gas turbine generator 6 is basically the rated output PWrad, and the gas turbine generator 6 outputs active power PWac and reactive power PWrac according to the rated output PWrad. Furthermore, since the bleed valve 32 is closed, the auxiliary turbine 33 is not driven. Furthermore, the clutch 43 is in a disengaged state, and a phase modifying step S3 is executed. In other words, the auxiliary generator 41 is in a no-load operation state, and only reactive power PWrac is output from this auxiliary generator 41. Furthermore, the switch 54b provided on the BESS-dedicated power line 51b is turned on, and the power stored in the power storage device 45 is discharged.

[0066] As described above, when the required output PWc is equal to or greater than the discharge output PWdis, which is greater than the rated output PWrad of the gas turbine 1, or when the change in the required output PWc per unit time is greater than a predetermined value, the gas turbine generator 6 outputs to the external power system 60 active power PWac and reactive power PWrac according to the rated output PWrad, the auxiliary generator 41 outputs reactive power PWrac, and the storage battery 46 outputs active power PWac.

[0067] If the opening and closing controller 105 determines in the discharge condition determination step S10 that the discharge conditions are not satisfied, that is, if the bleed valve 32 is not open, that is, if the bleed valve 32 is closed, it instructs the switch 54b provided on the BESS dedicated power line 51b to be turned off. As a result, the switch 54b is turned off, and the power stored in the power storage device 45 is no longer discharged (discharge stop step S12).

[0068] If the main controller 101 determines in the main power generation execution determination step S1 that main power generation will not be performed, the above-mentioned main power generation step S2 is not performed. Therefore, in this case, the gas turbine 1 does not drive, and the gas turbine generator 6 does not generate power. In this embodiment, in this case as well, the extraction valve 32 is closed, the clutch 43 is disengaged, and the compressed air in the intermediate casing 3 is not supplied to the auxiliary turbine 33 via the extraction line 31. This auxiliary turbine 33 does not drive, and the auxiliary generator 41 operates under no load. Therefore, the auxiliary generator 41 outputs reactive power PWrac to the outside (phase modifying step S13).

[0069] As described above, in this embodiment, even if the externally required output PWc is smaller than the output (intermediate output PWmid) corresponding to the minimum intake air flow rate of the gas turbine 1, the required output PWc can be accommodated. Moreover, in this embodiment, the power storage device 45 is provided, and therefore the power generated by the auxiliary generator 41 can be stored. Therefore, in this embodiment, it is possible to respond more flexibly to changes in the output from the entire plant than in a case where the storage battery 46 is not provided. Moreover, in this embodiment, it is possible to appropriately manage the timing of charging the power storage device 45 and the timing of discharging the power storage device 45 by controlling the operation of the switch 54b related to this power storage device 45. Therefore, in this embodiment, it is possible to respond more flexibly to changes in the output from the entire plant.

[0070] In this embodiment, when the bleed valve 32 is closed and bleed air from the gas turbine 1 does not flow into the auxiliary turbine 33, the clutch 43 is disengaged, the rotor of the auxiliary generator 41 rotates freely, and the system is in a no-load operation state. Therefore, in this embodiment, when the bleed valve 32 is closed, the auxiliary generator 41 outputs reactive power PWrac. Also, in this embodiment, when the bleed valve 32 is open, bleed air from the gas turbine 1 flows into the auxiliary turbine 33, and the auxiliary generator 41 generates electricity by driving the auxiliary turbine 33, the auxiliary generator 41 outputs active power PWac and reactive power PWrac. That is, in this embodiment, whether the bleed valve 32 is closed or open, the auxiliary generator rotor 41ra rotates, and the auxiliary generator 41 supplies reactive power PWrac to the external power system 60. Therefore, in this embodiment, the voltage of the external power system 60 can be stabilized. Furthermore, in this embodiment, the inertial force of the auxiliary generator rotor 41ra can stabilize the frequency of the external power system 60. In particular, in this embodiment, a flywheel is fixed to the auxiliary generator rotor 41ra as the inertial body 41i, so the inertial force of the rotating body in this auxiliary generator 41 is increased, and the frequency of the external power system 60 can be stabilized more than in the case where there is no flywheel.

[0071] In this embodiment, the switching controller 105 controls the on / off state of the switch 54b provided on the BESS dedicated power line 51b in accordance with the discharge conditions, etc. However, the on / off state of the switch 54b provided on the BESS dedicated power line 51b does not have to be controlled in accordance with the discharge conditions, etc. In this case, the switch 54b is kept in the on state except in the event of an emergency. The charging process S8 and the discharging process S11 for the storage battery 46 are executed in accordance with the voltage difference between the voltage of the storage battery 46 and the voltage of the external power system 60.

[0072] "Second embodiment of gas turbine power plant" A second embodiment of a gas turbine power plant according to the present disclosure will be described below with reference to FIG.

[0073] Similar to the gas turbine power plant of the first embodiment, the gas turbine power plant of this embodiment includes a gas turbine 1, a waste heat utilization facility 20, a gas turbine generator 6, a steam extraction facility 30 capable of extracting steam, an auxiliary power generation facility 40a, a power system facility 50, and a control device 100. However, unlike the auxiliary power generation facility 40 of the first embodiment, the auxiliary power generation facility 40a of this embodiment does not include a power storage device 45. In this regard, the power system facility 50a of this embodiment does not include the BESS dedicated power line 51b of the first embodiment, nor the transformer 53b and the switch 54b provided on this BESS dedicated power line 51b.

[0074] As described in the first embodiment, the external power system 60 connected to the external connection power line 51c in this embodiment is also connected to the power storage device 65.

[0075] Similar to the plant in the first embodiment described with reference to Fig. 3, the plant in this embodiment also executes a main power generation execution determination step S1, a main power generation step S2, a phase modifying step S3, an extraction condition determination step S4, an extraction step S5, an auxiliary power generation step S6, a phase modifying cancellation step S7, and an extraction cancellation step S9. Therefore, similar to the plant in the first embodiment, the plant in this embodiment can also respond to an externally requested output PWc even if the requested output PWc is smaller than the output (intermediate output PWmid) corresponding to the minimum intake air flow rate of the gas turbine 1. Furthermore, similar to the plant in the first embodiment, the plant in this embodiment can also stabilize the voltage and frequency of the external power grid 60.

[0076] However, as described above, the plant in this embodiment does not have the power storage device 45 of the plant in the first embodiment, and therefore does not execute the charging step S8, the discharge condition determination step S10, the discharge step S11, and the discharge suspension step S12 in the flowchart shown in FIG. 3.

[0077] In the plant of the first embodiment, when the required output PWc becomes equal to or less than the extracted steam output PWbl that is less than the intermediate output PWmid, the extraction valve 32 opens, and the extraction process S5 is executed. Accompanying the execution of this extraction process S5, an auxiliary power generation process S6 and a charging process S8 are executed. Therefore, in the plant of the first embodiment, when the required output PWc becomes equal to or less than the extracted steam output PWbl, the auxiliary generator 41 generates power in the auxiliary power generation process S6, but the power PWra generated by this power generation is charged to the power storage device 45 in the charging process S8 and is not supplied to the external power grid 60.

[0078] On the other hand, in the gas turbine power plant of this embodiment, when the required output PWc becomes equal to or less than the extracted steam output PWbl, which is less than the intermediate output PWmid, the extraction valve 32 opens, and the extraction process S5 is performed. The auxiliary power generation process S6 is performed in conjunction with the execution of this extraction process S5, but the charging process S8 is not performed. Therefore, in this embodiment, the active power PWac, which is the electric power PWra generated by the power generation of the auxiliary generator 41 in the auxiliary power generation process S6, is supplied to the external electric power grid 60. Therefore, when the required output PWc becomes equal to or less than the extracted steam output PWbl, the output power of the entire plant in this embodiment is greater than the output power of the entire plant in the first embodiment. In this embodiment, the electric power from the auxiliary generator 41 is charged, for example, to a power storage device 45 connected to the external electric power grid 60.

[0079] As described above, when the required output PWc from the outside becomes equal to or less than the extraction steam output PWbl, stable combustion of the fuel can be achieved even if the fuel flow rate is set to a flow rate corresponding to the required output PWc. Furthermore, the combined power of the electric power from the gas turbine generator 6 and the electric power from the auxiliary generator 41 is less than the power that can be generated using the energy of the fuel supplied to the combustor 15. Therefore, even if the electric power from the auxiliary generator 41 is supplied to the external electric power system 60 in addition to the electric power from the gas turbine generator 6, as in this embodiment, the amount of electric power supplied from the entire plant to the external electric power system 60 can be made smaller than the amount of electric power generated by the gas turbine 1 when the intake air flow rate is minimum. In other words, in this embodiment, even if the electric power from the auxiliary generator 41 is supplied to the external electric power system 60 in addition to the electric power from the gas turbine generator 6, the amount of electric power supplied from the entire plant to the external electric power system 60 can be made smaller than the intermediate output PWmid of the gas turbine 1.

[0080] "Variations" In the above embodiment, the clutch 43 is disposed between the transmission 42 and the auxiliary generator 41. However, the clutch 43 may be disposed between the transmission 42 and the auxiliary turbine rotor 34. In this case, the output shaft 42o of the transmission 42 is connected to the auxiliary generator rotor 41ra, and the output shaft 42o of the clutch 43 is connected to the input shaft 42i of the transmission 42. When the clutch 43 is disposed between the transmission 42 and the auxiliary turbine rotor 34 in this way, the output shaft 42o of the transmission 42, which is connected to the auxiliary generator rotor 41ra, and the gear 42g fixed to this output shaft 42o can be used as the inertia body of the auxiliary generator rotor 41ra.

[0081] The gas turbine power plant in the above embodiment includes the exhaust heat utilization facility 20. However, the gas turbine power plant does not necessarily need to include the exhaust heat utilization facility 20.

[0082] Furthermore, the present disclosure is not limited to the embodiments and modifications described above, and various additions, modifications, substitutions, partial deletions, etc. are possible within the scope of the conceptual idea and spirit of the present invention as derived from the content defined in the claims and their equivalents.

[0083] "Addendum" The gas turbine power plants in the above-described embodiments and modifications can be understood, for example, as follows.

[0084] (1) A gas turbine power plant according to a first aspect includes: The gas turbine 1 has a compressor 10 capable of compressing air, a combustor 15 capable of burning fuel in the compressed air compressed by the compressor 10 to generate combustion gas, and a turbine 16 capable of being driven by the combustion gas, a gas turbine generator 6 connected to the gas turbine 1 and capable of generating electricity by driving the turbine 16, an extraction line 31 capable of extracting part of the compressed air generated by the compressor 10 as extraction air from the gas turbine 1, an auxiliary turbine 33 connected to the extraction line 31 and capable of being driven by the extraction air flowing through the extraction line 31, and a turbine 33 provided on the extraction line 31. the gas turbine generator 6 includes a bleed valve 32 for connecting the gas turbine generator 6 to the external power system 60, a synchronous auxiliary generator 41 connected to the auxiliary turbine 33 and capable of generating electricity by driving the auxiliary turbine 33, a clutch 43 capable of changing the connection state between the auxiliary turbine 33 and the auxiliary generator 41 between a transmission state in which the driving force of the auxiliary turbine 33 is transmitted to the auxiliary generator 41 and a disconnection state in which the driving force of the auxiliary turbine 33 is not transmitted to the auxiliary generator 41, a main generated power line 52m for electrically connecting the gas turbine generator 6 to an external power system 60, an auxiliary generated power line 52a for electrically connecting the auxiliary generator 41 to the external power system 60, and a control device 100. The control device 100 includes a bleed controller 104 for controlling the opening and closing of the bleed valve 32, and a clutch controller 106 for bringing the clutch 43 into the transmission state when the bleed valve 32 is open and bringing the clutch 43 into the disconnection state when the bleed valve 32 is closed.

[0085] In this aspect, by opening the bleed valve 32, part of the compressed air can be bled as bleed air to the outside of the gas turbine 1. Therefore, in this aspect, the flow rate of the compressed air flowing into the combustor 15 can be made smaller than the minimum intake air flow rate of the gas turbine 1. To ensure stable combustion of the fuel, fuel is supplied to the combustor 15 in accordance with the flow rate of the compressed air flowing into the combustor 15. Therefore, in this aspect, the flow rate of the combustion gas flowing into the turbine from the combustor 15 can be made smaller while ensuring stable combustion of the fuel. As a result, in this aspect, even if the externally required output PWc is smaller than the output corresponding to the minimum intake air flow rate of the gas turbine 1, the required output PWc can be met.

[0086] In this embodiment, when the bleed valve 32 is open, bleed air from the gas turbine 1 flows into the auxiliary turbine 33, driving the auxiliary turbine 33. At this time, the clutch 43 is in a transmission state, and the auxiliary generator 41 generates electricity by driving the auxiliary turbine 33. The auxiliary generator 41 outputs active power PWac and reactive power PWrac. In this embodiment, as described above, when the externally required output PWc is smaller than the output corresponding to the minimum intake air flow rate of the gas turbine 1, stable combustion of the fuel can be achieved even if the fuel flow rate is set to a flow rate corresponding to the required output PWc. Furthermore, the total power of the power PWr (active power PWac) from the gas turbine generator 6 and the power PWra (active power PWac) from the auxiliary generator 41 is less than the power that can be generated using the energy of the fuel supplied to the combustor 15. Therefore, even if electric power PWra from the auxiliary generator 41 is supplied to the external electric power system 60 in addition to electric power PWr from the gas turbine generator 6, the amount of electric power supplied from the entire plant to the external electric power system 60 can be made smaller than the amount of electric power generated by the gas turbine 1 when the intake air flow rate is minimum.

[0087] In this embodiment, when the bleed valve 32 is closed and bleed air from the gas turbine 1 does not flow into the auxiliary turbine 33, the clutch 43 is disengaged, the rotor of the auxiliary generator 41 rotates freely, and the system enters a no-load operation state. As a result, reactive power PWrac is output from the auxiliary generator 41 even when the bleed valve 32 is closed.

[0088] Therefore, in this aspect, whether the bleed valve 32 is closed or open, the rotor of the auxiliary generator 41 rotates and the reactive power PWrac is supplied from the auxiliary generator 41 to the external power grid 60. Therefore, in this aspect, it is possible to stabilize the voltage of the external power grid 60. Furthermore, in this aspect, it is possible to stabilize the frequency of the external power grid 60 by the inertial force of the rotor of the auxiliary generator 41.

[0089] (2) A gas turbine power plant according to a second aspect includes: In the gas turbine power plant according to the first aspect, the clutch controller 106 disengages the clutch 43 when the gas turbine generator 6 is not generating power.

[0090] In this embodiment, the rotor of the auxiliary generator 41 rotates even when the gas turbine generator 6 is not generating power. Therefore, in this embodiment, the voltage and frequency of the external power system 60 can be stabilized even when the gas turbine generator 6 is not generating power.

[0091] (3) A gas turbine power plant according to a third aspect includes: In the gas turbine power plant according to the first or second aspect, the auxiliary generator 41 includes a rotatable auxiliary generator rotor 41ra, an auxiliary generator casing 41c that covers the auxiliary generator rotor 41ra, and an inertial body 41i that is fixed to the auxiliary generator rotor 41ra and rotates integrally with the auxiliary generator rotor 41ra. The inertial body 41i has weight and is balanced around the central axis of rotation of the auxiliary generator rotor 41ra.

[0092] This embodiment can increase the inertial force of the rotor in the auxiliary generator 41. Therefore, this embodiment can stabilize the frequency of the external power system 60 more than when the inertial body 41i is not fixed to the auxiliary generator rotor 41ra.

[0093] (4) A gas turbine power plant according to a fourth aspect includes: The gas turbine power plant according to any one of the first to third aspects further includes a storage battery 46 capable of storing electric power generated by the auxiliary generator 41, and a storage battery power line 52b that electrically connects the storage battery 46 to the external electric power system 60 and also electrically connects the storage battery 46 to the auxiliary generator 41.

[0094] In this embodiment, the storage battery 46 can store the electric power PWra generated by the auxiliary generator 41. Therefore, in this embodiment, it is possible to more flexibly respond to changes in output from the entire plant than in a case where the storage battery 46 is not provided.

[0095] (5) A gas turbine power plant according to a fifth aspect includes: The gas turbine power plant according to the fourth aspect further includes a switch 54b that is provided in the battery power line 52b and that is capable of realizing an ON state in which the external power grid 60 and the auxiliary generator 41 are electrically connected to the storage battery 46, and an OFF state in which the external power grid 60 and the auxiliary generator 41 are not electrically connected to the storage battery 46. The control device 100 includes a switching controller 105 that instructs the switch 54b to switch to the ON state when a discharge condition is satisfied and the air bleed valve 32 is open, and that instructs the switch 54b to switch to the OFF state when the discharge condition is not satisfied and the air bleed valve 32 is not open. The discharge condition is that an externally requested output power PWc of the gas turbine 1 is greater than a rated output power PWrad of the gas turbine 1 and / or that a change amount per unit time of the externally requested output power PWc of the gas turbine 1 is greater than a predetermined value.

[0096] In this embodiment, by controlling the operation of the switch 54b, the timing of charging the storage battery 46 and the timing of discharging the storage battery 46 can be managed appropriately.

[0097] (6) A gas turbine power plant according to a sixth aspect comprises: In the gas turbine power plant according to any one of the first to fifth aspects, the bleed controller 104 instructs the bleed valve 32 to open when an actual output PWr that is an actual output of the gas turbine 1 becomes equal to or less than a predetermined bleed output PWbl that is smaller than a rated output PWrad of the gas turbine 1, and instructs the bleed valve 32 to close when the actual output PWr becomes larger than the bleed output PWbl.

[0098] In this aspect, when the actual output PWr of the gas turbine 1 becomes equal to or less than the extraction output PWbl which is smaller than the rated output PWrad of the gas turbine 1, the extraction valve 32 opens, and the flow rate of air flowing into the combustor 15 becomes smaller than the intake flow rate of the gas turbine 1. Therefore, in this aspect, even if the actual output PWr becomes equal to or less than the extraction output PWbl, the fuel can be stably combusted in the combustor 15.

[0099] (7) A gas turbine power plant according to a seventh aspect comprises: The gas turbine power plant according to any one of the first to sixth aspects further includes a fuel valve capable of adjusting a flow rate of fuel supplied to the combustor 15. The control device 100 includes a fuel controller 102 that determines an opening degree of the fuel valve in accordance with an externally required output PWc for the gas turbine 1 and instructs the fuel valve to set the opening degree.

[0100] In this embodiment, fuel can be supplied to the combustor 15 at a flow rate according to the required output PWc.

[0101] The operation method of the gas turbine power plant in the above-described embodiment and modified example can be understood, for example, as follows. (8) The method for operating a gas turbine power plant according to the eighth aspect is applied to the following gas turbine power plant. This gas turbine power plant includes a gas turbine 1 having a compressor 10 capable of compressing air, a combustor 15 capable of burning fuel in the compressed air compressed by the compressor 10 to generate combustion gas, and a turbine capable of being driven by the combustion gas, and a gas turbine generator 6 connected to the gas turbine 1, capable of generating electricity by driving the turbine and transmitting the electricity to an external power system 60. This gas turbine power plant operation method performs the following steps: a main power generation process S2 in which the gas turbine 1 is driven to cause the gas turbine generator 6 to generate power; an extraction process S5 in which, during the main power generation process S2, part of the compressed air generated by the compressor 10 is extracted as extracted air to the outside of the gas turbine 1 to reduce the flow rate of the compressed air flowing into the combustor 15; an auxiliary power generation process S6 in which, during the extraction process S5, an auxiliary turbine 33 is driven by the extracted air extracted to the outside of the gas turbine 1 to cause a synchronous auxiliary generator 41 to generate power by driving the auxiliary turbine 33; and a phase modifying process S3 in which, during the main power generation process S2, the auxiliary generator 41 is operated with no load when the extraction process S5 is not being performed.

[0102] In this embodiment, similar to the gas turbine power plant of the first embodiment, it is possible to flexibly respond to fluctuations in the external required output PWc. Also, in this embodiment, similar to the gas turbine power plant of the first embodiment, it is possible to stabilize the voltage and frequency of the external power grid 60.

[0103] (8) A method for operating a gas turbine power plant according to a ninth aspect includes the steps of: In the gas turbine power plant operation method according to the eighth aspect, the phase modifying step S3 is executed when the main power generating step S2 is not executed.

[0104] In this embodiment, similar to the gas turbine power plant in the second embodiment, the voltage and frequency of the external power system 60 can be stabilized even when the gas turbine generator 6 is not generating power.

[0105] (10) A method for operating a gas turbine power plant according to a tenth aspect includes the steps of: The method for operating a gas turbine power plant according to the eighth or ninth aspect further includes a charging step S8 of storing the electric power generated by the auxiliary generator 41 in a storage battery 46, and a discharging step S11 of discharging the electric power stored in the storage battery 46 from the storage battery 46 to the external electric power system 60.

[0106] In this embodiment, similar to the gas turbine power plant in the fourth embodiment, it is possible to deal more flexibly with changes in output from the entire plant than in the case where the storage battery 46 is not provided.

[0107] (11) An eleventh aspect of the present invention provides a method for operating a gas turbine power plant, comprising: In the gas turbine power plant operation method according to the tenth aspect, the discharging step S11 is executed when a discharging condition is satisfied, which is that an externally requested output PWc of the gas turbine 1 is greater than a rated output PWrad of the gas turbine 1, and / or that a change per unit time in the externally requested output PWc of the gas turbine 1 is greater than a predetermined value.

[0108] In this aspect, similar to the gas turbine power plant in the fifth aspect, the timing of charging the storage battery 46 and the timing of discharging the storage battery 46 can be appropriately managed.

[0109] (12) A method of operating a gas turbine power plant according to a twelfth aspect includes the steps of: In the method for operating a gas turbine power plant according to any one of the eighth to eleventh aspects, the extraction step S5 is executed when an actual output PWr that is an actual output of the gas turbine 1 becomes equal to or less than a predetermined extraction output PWbl that is smaller than a rated output PWrad of the gas turbine 1. When the actual output PWr becomes larger than the extraction output PWbl, the extraction step S5 is stopped.

[0110] In this embodiment, similar to the gas turbine power plant in the sixth embodiment, the fuel can be stably combusted in the combustor 15 even if the actual power output PWr becomes equal to or less than the extracted steam power output PWbl.

[0111] (13) A method of operating a gas turbine power plant according to a thirteenth aspect includes the steps of: In the gas turbine power plant operation method according to any one of the eighth to twelfth aspects, the gas turbine power plant includes a fuel valve capable of adjusting a flow rate of fuel supplied to the combustor 15. This operation method further includes a fuel control step S2a of determining a valve aperture of the fuel valve in accordance with an external required output PWc for the gas turbine 1, and instructing the fuel valve to change the valve aperture.

[0112] In this embodiment, similar to the gas turbine power plant of the seventh embodiment, a fuel flow can be supplied to the combustor 15 at a flow rate according to the required output PWc. [Explanation of symbols]

[0113] 1: Gas turbine 2: Gas turbine rotor 3: Intermediate casing 4: Fuel line 5: Fuel valve 6: Gas turbine generator 10: Compressor 11: Compressor rotor 11s: Compressor rotor shaft 11b: Moving blade row 12: Compressor casing 13: Intake volume regulator 13v: Inlet guide vane (IGV) 13d: Drive unit 15: Combustor 16: Turbine 17: Turbine rotor 17s: Turbine rotor shaft 17b: Moving blade row 18: Turbine casing 20: Waste heat utilization equipment 21: Waste heat recovery boiler 21d: Duct 21t: Heat transfer tube 22: Chimney 23: Steam turbine 24: Main steam line 25: Condenser 26: Water supply line 27: Water supply pump 30: Air extraction equipment 31: Bleed line 32: Bleed valve 33: Auxiliary turbine 34: Auxiliary turbine rotor 35: Auxiliary turbine casing 40, 40a: Auxiliary power generation equipment 41: Auxiliary generator 41ra: Auxiliary generator rotor 41rb: rotor 41c: Auxiliary generator casing 41s: Stator 41i: Inertial body 42: Transmission 42i: Input shaft 42o: Output shaft 42g: Gears 43: Clutch 43i: Input shaft 43o: Output shaft 43m: Clutch mechanism 45: Power storage device 46: Storage battery 47: AC / DC converter 50,50a: Power system equipment 51g: Dedicated power line for GT generator 51a: Dedicated power line for automatic generators 51b: BESS dedicated power line 51p: Shared power lines within the plant 51c: External power line 52m: Main power line 52a: Auxiliary power generation line 52b: Battery power line 53a, 53b, 53c, 53g: Transformers 54a, 54b, 54c, 54g: Switch 55: Output meter 60: External power system 65: Power storage device 66: Storage battery 67: AC / DC converter 100: Control device 101: Main controller 102: Fuel controller 103:IGV controller 104: Bleed air controller 105: Opening and closing controller 106: Clutch controller A: Air F:Fuel PWr: Actual output PWc: Request output PWrad: Rated power PWmid: Medium output PWbl: Extraction power PWac: Active power PWrac: reactive power Ar: rotor axis Da: Axial direction Dau: Axis upstream side Dad: Downstream of the axis

Claims

1. a gas turbine including a compressor capable of compressing air, a combustor capable of burning fuel in the compressed air compressed by the compressor to generate combustion gas, and a turbine capable of being driven by the combustion gas; a gas turbine generator connected to the gas turbine and capable of generating electricity by driving the turbine; an extraction line that allows a portion of the compressed air generated by the compressor to be extracted from the gas turbine as extraction air; an auxiliary turbine connected to the extraction line and capable of being driven by the extraction air flowing through the extraction line; a bleed valve provided in the bleed line; a synchronous auxiliary generator connected to the auxiliary turbine and capable of generating electricity by driving the auxiliary turbine; a clutch capable of changing a connection state between the auxiliary turbine and the auxiliary generator between a transmission state in which the driving force of the auxiliary turbine is transmitted to the auxiliary generator and a disconnection state in which the driving force of the auxiliary turbine is not transmitted to the auxiliary generator; a main power generation line electrically connecting the gas turbine generator to an external power system; an auxiliary generated power line electrically connecting the auxiliary generator and the external power system; a control device; Equipped with The control device a bleed controller for controlling the opening and closing of the bleed valve; a clutch controller that brings the clutch into the transmission state when the bleed valve is open and brings the clutch into the disengaged state when the bleed valve is closed; having A gas turbine power plant comprising:

2. 2. The gas turbine power plant according to claim 1, the clutch controller disengages the clutch when the gas turbine generator is not generating power. Gas turbine power plant.

3. 2. The gas turbine power plant according to claim 1, the auxiliary generator includes a rotatable auxiliary generator rotor, an auxiliary generator casing that covers the auxiliary generator rotor, and an inertial body that is fixed to the auxiliary generator rotor and is rotatable integrally with the auxiliary generator rotor; the inertial body is an object having weight and balanced around the central axis of rotation of the auxiliary generator rotor; Gas turbine power plant.

4. The gas turbine power plant according to any one of claims 1 to 3, a storage battery capable of storing the power generated by the auxiliary generator; a battery power line that electrically connects the storage battery to the external power system and electrically connects the storage battery to the auxiliary generator; Further provided with Gas turbine power plant.

5. 5. The gas turbine power plant according to claim 4, a switch that is provided in the storage battery power line and that can realize an ON state in which the external power system and the auxiliary generator are electrically connected to the storage battery, and an OFF state in which the external power system and the auxiliary generator are not electrically connected to the storage battery, the control device has an opening / closing controller that instructs the switch to be in the on state when a discharge condition is satisfied and the air bleed valve is open, and that instructs the switch to be in the off state when the discharge condition is not satisfied and the air bleed valve is not open, The discharge conditions are: The external power demand for the gas turbine is greater than the rated power output of the gas turbine, and / or a change amount per unit time in an output required from an external source to the gas turbine is greater than a predetermined value; That is, Gas turbine power plant.

6. The gas turbine power plant according to any one of claims 1 to 3, the bleed controller instructs the bleed valve to open when an actual output, which is an actual output of the gas turbine, becomes equal to or less than a predetermined bleed output which is smaller than a rated output of the gas turbine, and instructs the bleed valve to close when the actual output becomes larger than the bleed output. Gas turbine power plant.

7. The gas turbine power plant according to any one of claims 1 to 3, a fuel valve capable of adjusting the flow rate of fuel supplied to the combustor; the control device includes a fuel controller that determines an opening degree of the fuel valve in response to an externally required output of the gas turbine and instructs the fuel valve to set the opening degree. Gas turbine power plant.

8. a gas turbine including a compressor capable of compressing air, a combustor capable of burning fuel in the compressed air compressed by the compressor to generate combustion gas, and a turbine capable of being driven by the combustion gas; a gas turbine generator connected to the gas turbine, capable of generating electricity by driving the turbine and transmitting the electricity to an external power system; A method for operating a gas turbine power plant comprising: a main power generation process of driving the gas turbine to cause the gas turbine generator to generate electricity; an extraction process of extracting a portion of the compressed air generated by the compressor as extraction air to outside the gas turbine during the main power generation process, thereby reducing a flow rate of the compressed air flowing into the combustor; an auxiliary power generation process in which an auxiliary turbine is driven by the extracted air extracted to the outside of the gas turbine during the extraction process, and a synchronous auxiliary generator is caused to generate electricity by driving the auxiliary turbine; a phase modifying step of operating the auxiliary generator under no load when the steam extraction step is not being performed during the main power generation step; To execute A method for operating a gas turbine power plant.

9. 9. The method for operating a gas turbine power plant according to claim 8, The phase modifying step is performed when the main power generating step is not being performed. A method for operating a gas turbine power plant.

10. The method for operating a gas turbine power plant according to claim 8 or 9, a charging step of storing the electric power generated by the auxiliary generator in a storage battery; a discharging step of discharging the electric power stored in the storage battery from the storage battery to the external electric power system; Then, A method for operating a gas turbine power plant.

11. 11. The method for operating a gas turbine power plant according to claim 10, When the discharge condition is satisfied, the discharge step is carried out; The discharge conditions are: The external power demand for the gas turbine is greater than the rated power output of the gas turbine, and / or a change amount per unit time in an output required from an external source to the gas turbine is greater than a predetermined value; That is, A method for operating a gas turbine power plant.

12. The method for operating a gas turbine power plant according to claim 8 or 9, When an actual output, which is an actual output of the gas turbine, becomes equal to or less than a predetermined extraction output which is smaller than a rated output of the gas turbine, the extraction step is performed; When the actual output becomes larger than the bleed output, the bleed process is stopped. A method for operating a gas turbine power plant.

13. The method for operating a gas turbine power plant according to claim 8 or 9, the gas turbine power plant includes a fuel valve capable of adjusting a flow rate of fuel supplied to the combustor; a fuel control step of determining valve openings of the fuel valves in response to an externally required output of the gas turbine and instructing the fuel valves to change the valve openings; A method for operating a gas turbine power plant.

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