JP2013221423A - Control device for gas turbine, gas turbine, and control method for gas turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten starting time while maintaining safety.SOLUTION: A gas turbine comprises a compressor for producing compressed air by compressing air taken from an air inlet, a combustor for producing a combustion gas by burning fuel with the compressed air, and a turbine driven by the combustion gas. The control device 40 for a gas turbine comprises a rotational acceleration determining part 48 for determining the maximum rotational acceleration feasible by the turbine based on a safety index showing the relationship between damage of the appliances comprising the gas turbine and the rotational acceleration of the turbine, and an acceleration fuel-air ratio determining part 50 for determining the fuel-air ratio of the combustor for accelerating the turbine by the rotational acceleration determined by the rotational acceleration determining part 48.

Description

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

Conventionally, a gas turbine has been started according to a fixed schedule according to a startup mode determined in advance according to the stop time of the gas turbine.
In contrast, Patent Document 1 discloses the physical characteristics of air taken in by a compressor, the physical characteristics of the compressor, the physical characteristics of the fuel, the physical characteristics of the fuel supply system, and the current state of the gas turbine. A start-up method for determining the air-fuel ratio based on the operation data regarding the operation parameters is described. In the start-up method described in Patent Document 1, the start-up schedule is changed flexibly according to the surrounding conditions and the equipment state of the gas turbine, so that the start-up time of the turbine can be shortened.

JP 2011-132594 A

  However, if the startup schedule is changed in accordance with the surrounding conditions and the equipment state of the gas turbine, there is a possibility that the operation of the gas turbine becomes unstable and the risk of equipment damage increases.

  The present invention has been made in view of such circumstances, and provides a gas turbine control device, a gas turbine, and a gas turbine control method capable of reducing start-up time while maintaining safety. The purpose is to do.

  In order to solve the above problems, the gas turbine control device, gas turbine, and gas turbine control method of the present invention employ the following means.

  A control apparatus for a gas turbine according to a first aspect of the present invention includes a compressor that generates compressed air by compressing air taken from an air intake port, and a combustion that generates combustion gas by burning fuel with the compressed air And a gas turbine control device including a turbine driven by the combustion gas, based on a first index indicating a relationship between damage of equipment constituting the gas turbine and rotational acceleration of the turbine, Rotational acceleration determining means for determining the maximum rotational acceleration possible for the turbine, and accelerated fuel for determining a fuel-air ratio of the combustor so that the turbine is accelerated at the rotational acceleration determined by the rotational acceleration determining means. And an air ratio determining means.

According to this configuration, the gas turbine includes a compressor that generates compressed air by compressing air taken from the air intake port, a combustor that generates combustion gas by burning fuel with the compressed air, and a combustion gas. A driving turbine is provided.
The maximum rotational acceleration possible for the turbine is determined by the rotational acceleration determining means based on the first index indicating the relationship between damage of equipment constituting the gas turbine and the rotational acceleration of the turbine.
As the rotational acceleration of the turbine increases, the time for the turbine rotation speed to reach a predetermined operation rotation speed, that is, the startup time of the gas turbine is shortened. However, depending on the rotational acceleration of the turbine, the influence on the equipment constituting the gas turbine is increased, which may cause damage. That is, the first index is an index that indicates the possibility of equipment damage that occurs when the rotational acceleration of the turbine increases.

Then, the fuel / air ratio of the combustor is determined by the accelerated fuel / air ratio determining means so that the turbine is accelerated by the rotational acceleration of the turbine determined by the rotational acceleration determining means.
As described above, in this configuration, the maximum rotational acceleration that the turbine can perform is determined based on the first index indicating the relationship between the damage of the equipment constituting the gas turbine and the rotational acceleration of the turbine. The start-up time can be shortened while maintaining the above.

  In the first aspect, the first index is the relationship between the contact of the turbine blades on the casing and the rotational acceleration of the turbine, the relationship between the surging of the compressor and the rotational acceleration of the turbine, and the exhaust of the turbine. It is preferable that the relationship is at least one of the relationship between the gas temperature and the rotational acceleration of the turbine.

  According to this structure, the influence which the rotational acceleration of a turbine has on an apparatus can be avoided easily.

  In the first aspect, the physical quantity in the case where the combustor is ignited based on the second index indicating the relationship between the physical quantity relating to fuel or air and the fuel-air ratio, which allows the fuel to be stably combusted by the combustor. It is preferable to include ignition fuel / air ratio determining means for determining the fuel / air ratio.

According to this structure, the 2nd parameter | index which showed the relationship between the physical quantity regarding fuel or air and fuel-air ratio which can burn a fuel stably with a combustor is predetermined. Then, the ignition fuel / air ratio determining means determines the physical quantity and fuel / air ratio related to fuel or air when the combustor is ignited based on the second index.
The second index is an index indicating the possibility of occurrence of an event that is undesirable for the operation of the gas turbine due to fuel combustion.
Thereby, this structure can perform more stable starting.

  In the first aspect, the second index indicates a region in which flashback and misfire do not occur, a relationship between a fuel-air mixed gas or air jet velocity and a fuel-air ratio, and a region in which combustion vibration does not occur. In addition, it is preferable that at least one of the relationship between the pilot ratio and the fuel-air ratio, which is the ratio of the pilot fuel flow rate to the total fuel flow rate.

  According to this structure, the influence which the combustion of a fuel has on an apparatus can be avoided easily.

  In the first aspect, when the fuel is purged, the rotation speed of the compressor is determined according to the output of the thyristor in order to rotate the compressor by an electric motor controlled using a thyristor. It is preferable to include a rotation speed determination means.

According to this configuration, when the fuel is purged, the compressor is rotated by an electric motor controlled using a thyristor. The electric motor is a generator connected to a turbine and a compressor, for example. When purging the fuel, the rotational speed determining means determines the rotational speed of the compressor according to the output of the thyristor. The larger the thyristor output, the faster the compressor speed and the shorter the purge time.
Therefore, this configuration can optimize the purge time according to the output of the thyristor.

  A gas turbine according to a second aspect of the present invention includes a compressor that compresses air taken in from an air intake port to generate compressed air, a combustor that burns fuel with the compressed air and generates combustion gas, and A turbine driven by the combustion gas, and the control device described above.

  A method for controlling a gas turbine according to a third aspect of the present invention includes a compressor that compresses air taken in from an air intake to generate compressed air, and combustion that generates combustion gas by burning fuel with the compressed air And a gas turbine control method including a turbine driven by the combustion gas, based on a first index indicating a relationship between damage of equipment constituting the gas turbine and rotational acceleration of the turbine, A first step of determining a maximum rotational acceleration that the turbine is capable of, and a second step of determining a fuel-air ratio of the combustor such that the turbine is accelerated at the determined rotational acceleration.

  According to the present invention, there is an excellent effect that the startup time can be shortened while maintaining safety.

1 is a configuration diagram of a gas turbine according to a first embodiment of the present invention. It is a functional block diagram which shows the function of the control apparatus which concerns on 1st Embodiment of this invention. It is the figure which showed an example of the safety index based on 1st Embodiment of this invention. It is a flowchart which shows the flow of the gas turbine starting process which concerns on 1st Embodiment of this invention. It is the figure which showed an example of the combustion stability parameter | index which concerns on 2nd Embodiment of this invention. It is a flowchart which shows the flow of the gas turbine starting process which concerns on 2nd Embodiment of this invention. It is a figure required for description of determination of the ignition fuel-air ratio which concerns on 2nd Embodiment of this invention. It is the graph which showed the relationship between the thyristor output which concerns on 3rd Embodiment of this invention, and rotation speed. It is the graph which showed the relationship between the purge rotation speed which concerns on 3rd Embodiment of this invention, and purge time. It is a flowchart which shows the flow of the gas turbine starting process which concerns on 3rd Embodiment of this invention. It is a flowchart which shows the flow of the gas turbine starting process which concerns on 3rd Embodiment of this invention.

  Hereinafter, an embodiment of a gas turbine control device, a gas turbine, and a gas turbine control method according to the present invention will be described with reference to the drawings.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of a gas turbine 10 according to the first embodiment.

  The gas turbine 10 includes a turbine 12 and a compressor 14 that are turbomachines, and a combustor 16.

  The compressor 14 is driven by the rotating shaft 18 to compress the air taken in from the air intake port and generate compressed air. An inlet guide vane (IGV) 20 that controls the flow rate of air guided to the compressor 14 is provided at the inlet of the compressor 14.

  The combustor 16 injects fuel into the compressed air introduced from the compressor 14 into the passenger compartment 22 to generate high-temperature and high-pressure combustion gas.

  The turbine 12 is rotationally driven by the combustion gas generated in the combustor 16.

  A bypass pipe 24 is provided between the passenger compartment 22 and the combustor 16, and the bypass pipe 24 is used when the air in the combustor 16 becomes insufficient due to load fluctuations of the turbine 12. When the bypass valve 26 is opened, it becomes a flow path for introducing the air in the passenger compartment 22 into the combustor 16. In addition, an extraction pipe 28 for introducing cooling air from the compressor 14 to the turbine 12 is provided between the compressor 14 and the turbine 12.

The turbine 12, the compressor 14, and the generator 30 are connected by the rotating shaft 18, and the rotational driving force generated in the turbine 12 is transmitted to the compressor 14 and the generator 30 by the rotating shaft 18. Then, the generator 30 generates power by the rotational driving force of the turbine 12.
The generator 30 is also used as an electric motor using a thyristor, and rotates the turbine 12 and the compressor 14 when the gas turbine 10 is started. That is, in the gas turbine 10 according to the present embodiment, the rotational speed at the start of the turbine 12 and the compressor 14 is controlled by the thyristor.

The combustor 16 is provided with a pilot nozzle 32P and a main nozzle 32M. A plurality of main nozzles 32M (for example, eight, not shown) are provided so as to surround the pilot nozzle 32P. The pilot nozzle 32P is supplied with pilot fuel whose pressure difference before and after the flow rate adjustment valve 36P is adjusted by the pressure adjustment valve 34P and whose flow rate is adjusted by the flow rate adjustment valve 36P. On the other hand, the main nozzle 32M is supplied with main fuel whose flow rate is adjusted by the flow rate adjusting valve 36M after the differential pressure across the flow rate adjusting valve 36M is adjusted by the pressure adjusting valve 34M.
The pressure adjustment valve 34P and the pressure adjustment valve 34M may be a common pressure adjustment system in which both are combined into one.
The combustor 16 mixes and burns the pilot fuel supplied from the pilot nozzle 32P and compressed air, and also mixes and burns the main fuel and compressed air supplied from the main nozzle 32M.

Further, the gas turbine 10 includes a control device 40 that controls the entire gas turbine 10.
FIG. 2 is a functional block diagram illustrating functions of the control device 40 relating to the start of the gas turbine 10 according to the first embodiment. The control device 40 includes, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), and a computer-readable storage device. A series of processes for realizing various functions of the purge rotational speed determination unit 44, the ignition fuel / air ratio determination unit 46, the rotational acceleration / air determination unit 48, and the acceleration / fuel ratio determination unit 50 shown in FIG. Are stored in the storage unit 42 or RAM, which is a storage device, in the form of a program, and various functions are realized by the CPU reading this program into the RAM and executing information processing / arithmetic processing. .

  The purge rotation speed determination unit 44 rotates the compressor 14 to send air to the combustor 16 and determines the rotation speed of the compressor 14 for purging the fuel (hereinafter referred to as “purge rotation speed”). . Purging is, for example, blowing off fuel remaining in the combustor 16 with air to the outside of the combustor 16 and can suppress abnormal combustion when the gas turbine 10 is started.

  The ignition / fuel ratio determination unit 46 determines a fuel / air ratio (hereinafter referred to as “ignition fuel / air ratio”) when the combustor 16 is ignited.

  The rotational acceleration determining unit 48 determines rotational acceleration for increasing the rotational speed (rotational speed) of the turbine 12 to a predetermined operating speed (for example, rated speed).

  The acceleration fuel / air ratio determining unit 50 determines the fuel / air ratio of the combustor 16 so that the turbine 12 is accelerated by the rotational acceleration determined by the rotational acceleration determining unit 48.

  In addition, the storage unit 42 according to the first embodiment stores a safety index indicating the relationship between the damage of equipment constituting the gas turbine 10 and the rotational acceleration of the turbine 12. The larger the rotational acceleration of the turbine 12, the shorter the time for the rotational speed of the turbine 12 to reach the operating rotational speed, that is, the startup time of the gas turbine 10. However, depending on the rotational speed acceleration of the turbine 12, the influence on the equipment constituting the gas turbine 10 is increased, which may cause damage. That is, the safety index is an index indicating the possibility of equipment damage that occurs when the rotational acceleration of the turbine 12 increases.

  FIG. 3 is a diagram illustrating an example of the safety index.

FIG. 3A is a graph showing the safety index in relation to the contact of the turbine blade with the casing (hereinafter referred to as “blade contact”) and the rotational acceleration of the turbine 12.
The blade contact is an event in which the turbine rotor blade and the casing come into contact with each other due to unsteady hot stretching between the casing 22 side and the rotating equipment (rotor and turbine rotor blade) when the gas turbine 10 is started or stopped. is there.
As shown in FIG. 3A, when the rotational acceleration of the turbine 12 increases, the temperature of the combustion gas also increases accordingly, so that the possibility of blade contact increases, and the equipment safety level decreases. Rotational acceleration with a device safety level below the hazardous area is not suitable for use.

FIG. 3B is a graph showing the safety index as a relationship between the surging of the compressor 14 (hereinafter referred to as “compressor surge”) and the rotational acceleration of the turbine 12.
The compressor surge is an event in which the compressor 14 causes a kind of self-excited vibration and the discharge pressure and the flow rate fluctuate when the compressed air has a low flow rate.
As shown in FIG. 3 (b), when the rotational acceleration of the turbine 12 decreases, the flow rate of the compressed air decreases accordingly, so that the possibility of a compressor surge increases, and the equipment safety level decreases.

FIG. 3C is a graph showing the relationship between the exhaust gas temperature of the turbine 12 and the rotational acceleration of the turbine 12.
If the exhaust gas temperature of the turbine 12 exceeds the allowable temperature of the exhaust duct (not shown), the exhaust duct will be damaged.
As shown in FIG. 3 (c), when the rotational acceleration of the turbine 12 increases, the exhaust gas temperature also increases accordingly, so that the possibility of damage to the exhaust duct increases and the equipment safety level decreases.

  FIG. 4 is a flowchart showing the flow of the gas turbine starting process executed by the control device 40 when starting the gas turbine 10.

  First, in step 100, the turbine 12 and the compressor 14 which are turbo machines are started. The start-up here means that the operator gives a start command to the turbine 12 and the compressor 14 that are stopped. Thereby, the generator 30 starts operation as an electric motor.

  In the next step 102, the purge rotational speed is determined. In the first embodiment, the purge rotational speed determination unit 44 determines the rotational speed of the compressor 14 selected by the operator as the purge rotational speed.

  In the next step 104, the compressor 14 is accelerated by using the generator 30 as an electric motor.

  In the next step 106, it is determined whether or not the purging of the combustor 16 has been completed. If the determination is affirmative, the process proceeds to step 108, and if the determination is negative, the process returns to step 104. Whether or not the purge is completed is determined based on whether or not the rotational speed of the compressor 14 has reached the purge rotational speed, whether or not the purge rotational speed has continued for a predetermined time, and the like.

  In step 108, the ignition fuel / air ratio of the combustor 16 is determined. In the first embodiment, the ignition / fuel ratio determination unit 46 determines a predetermined fuel / air ratio as the ignition / fuel ratio.

  In the next step 110, the pressure adjustment valve 34P and the pressure adjustment valve 34M are controlled so that the differential pressures before and after the flow adjustment valve 36P of the pilot fuel and the flow adjustment valve 36M of the main fuel become predetermined values, and the determined ignition is determined. The opening degree of the flow rate adjustment valve 36M and the flow rate adjustment valve 36M is controlled so that the fuel / air ratio is obtained, the fuel is ignited, and combustion gas is generated from the combustor 16.

In the next step 112, the rotational acceleration of the turbine 12 is determined. In the first embodiment, the rotational acceleration determination unit 48 determines the maximum rotational acceleration that the turbine 12 is capable of based on the safety index stored in the storage unit 42.
Specifically, the rotational acceleration determination unit 48 does not cause damage to the blade contact, the compressor surge, and the exhaust duct based on the safety index shown in FIG. 3, that is, the equipment safety level is included in the dangerous area. Select and determine not the maximum rotational acceleration.

  In the next step 114, the accelerated fuel / air ratio determining unit 50 determines the accelerated fuel / air ratio so that the turbine 12 is accelerated at the determined rotational acceleration.

  In the next step 116, fuel is burned at the determined acceleration fuel-air ratio, and the turbine 12 is accelerated.

  In the next step 118, it is determined whether or not the speed of the turbine 12 has reached the operating speed. If the determination is negative, the process returns to step 116, and the turbine 12 continues to be accelerated. finish.

  As described above, the control device 40 of the gas turbine 10 according to the first embodiment is based on the safety index indicating the relationship between the damage of the equipment constituting the gas turbine 10 and the rotational acceleration of the turbine 12. A rotational acceleration determining unit 48 that determines the maximum rotational acceleration that the turbine 12 is capable of, and an accelerated fuel air that determines the fuel-air ratio of the combustor 14 so that the turbine is accelerated at the rotational acceleration determined by the rotational acceleration determining unit 48. A ratio determining unit 50. Thereby, the gas turbine 10 can shorten start-up time, maintaining safety.

  The safety index is a relationship between the blade contact and the rotational acceleration of the turbine 12, a relationship between the compressor surge and the rotational acceleration of the turbine 12, and a relationship between the exhaust gas temperature of the turbine 12 and the rotational acceleration of the turbine 12. Therefore, the gas turbine 10 can easily avoid the influence of the rotational acceleration of the turbine 12 on the equipment.

  In the first embodiment, as the safety index, the relationship between the blade contact and the rotational acceleration of the turbine 12, the relationship between the compressor surge and the rotational acceleration of the turbine 12, and the exhaust gas temperature and the rotational acceleration of the turbine 12 are However, the present invention is not limited to this, and at least one of them may be used.

  Moreover, although the memory | storage part 42 demonstrated the form in which the memory | storage part 42 memorize | stores a safety index beforehand in this 1st Embodiment, this invention is not limited to this, and a safety index is the time of starting of a gas turbine. It is good also as a form suitably corrected based on the form produced | generated by simulation, the surrounding conditions of the gas turbine 10, and a stop time.

[Second Embodiment]
Hereinafter, a second embodiment of the present invention will be described.

  The configuration of the gas turbine 10 according to the second embodiment is the same as the configuration of the gas turbine 10 according to the first embodiment shown in FIGS.

  In addition, the memory | storage part 42 which concerns on this 2nd Embodiment has memorize | stored the combustion stability parameter | index which showed the relationship between the physical quantity regarding fuel or air, and fuel-air ratio which can combust a fuel stably with the combustor 16. FIG. That is, the combustion stability index is an index that indicates the possibility of occurrence of an undesirable event for the operation of the gas turbine 10 due to fuel combustion. The physical quantity related to fuel or air is the flow rate or flow rate of fuel or air.

  FIG. 5 is a diagram showing an example of the combustion stability index.

FIG. 5A is a map (hereinafter referred to as “Map 1”) showing the relationship between the fuel / air mixture flow rate or fuel / air ratio and the fuel / air mixed gas or air jetting region, which shows the region where flashback and misfire do not occur. is there. Backfire is also referred to as flashback, and is an event in which the flame returns to the upstream side from the normal flame position due to the low jet flow velocity, damaging the equipment. Misfire is an event in which the flame blows off due to the high jet velocity.
As shown in FIG. 5A, a region where the fuel-air ratio and the jet velocity are balanced is a region where backfire and misfire do not occur.

FIG. 5B shows a region where no combustion vibration occurs, and a map showing the relationship between the pilot ratio, which is the ratio of the pilot fuel flow rate to the total fuel flow rate, and the fuel-air ratio (hereinafter referred to as “map 2”). ). Combustion vibrations are pressure fluctuations that occur in the combustor 16 as the combustion becomes unstable, and excessive fuel vibrations cause damage to the combustor 16 and other components.
As shown in FIG. 5B, a region where the fuel-air ratio and the pilot ratio are balanced is a region where combustion vibration does not occur.

  FIG. 6 is a flowchart showing the flow of the gas turbine startup process executed by the control device 40 according to the second embodiment. In FIG. 6, the same steps as those in FIG. 4 are denoted by the same reference numerals as those in FIG.

  In step 106, it is determined whether or not the combustor 16 has been purged. If the determination is affirmative, the process proceeds to step 108 '. If the determination is negative, the process returns to step 104.

  In step 108 ', the ignition fuel / air ratio of the combustor 16 is selected. In the second embodiment, the ignition / fuel ratio determination unit 46 selects the ignition / fuel ratio based on the combustion stability index.

  In the next step 109, it is determined whether or not the ignition fuel / air ratio is located in a stable region. For example, since the air density also changes depending on the atmospheric temperature, the weight flow rate of the air changes. For this reason, it is necessary to determine whether or not the ignition / fuel ratio is located in the stable region every time the gas turbine 10 is started. If the determination in step 109 is affirmative, the selected ignition / fuel ratio is determined as the ignition / fuel ratio used to start the gas turbine 10, and the process proceeds to step 110. If the determination is negative, the process returns to step 108 'and ignition is performed. Reselect the fuel-air ratio.

  As an example, the determination of the ignition / fuel ratio according to the second embodiment will be described with reference to FIG.

Point A is an initial operating point and is located in the stable region in map 2, but is located in the misfire region in map 1 shown in FIG. 7 (a).
Therefore, in order to position the operating point in the stable region of the map 1, the control device 40 reduces the air flow rate and corrects to the point B. In this case, since the start-up time is extended when the rotational speed of the compressor 14 is reduced, it is preferable to adjust the air flow rate by controlling the opening degree of the inlet guide vane 20 within a range where the compressor surge does not occur.

As a result, the operating point of the point B is located in the stable region in the map 1, but is located in the combustion vibration region in the map 2 shown in FIG. 7B.
Therefore, in order to position the operating point in the stable region of the map 2, the pilot ratio is reduced by controlling the opening degree of the flow rate adjusting valves 36P and 36M while the air flow rate is maintained, and the point C is corrected.

  Since the operating point of point C is located in the stable region in both maps 1 and 2, the control device 40 ignites the combustor 16 at the operating point of point C.

  As described above, the control device 40 of the gas turbine 10 according to the second embodiment controls the combustor 16 based on the combustion stability index indicating the fuel-air ratio at which the fuel is stably combusted by the combustor 16. An ignition fuel / air ratio determining unit 46 is provided for determining an ignition / fuel ratio when igniting. Therefore, the gas turbine 10 according to the second embodiment can perform more stable startup.

  Combustion stability index is the relationship between the jet velocity of mixed gas or air and the fuel-air ratio, which indicates the region where no flashback or misfire occurs, and the relationship between the pilot ratio and the fuel-air ratio, which indicates the region where combustion oscillation does not occur It is. Therefore, the gas turbine 10 according to the second embodiment can easily avoid the influence of fuel combustion on the equipment.

  In the second embodiment, the relationship between the jetting flow velocity of the mixed gas and the fuel / air ratio and the relationship between the pilot ratio and the fuel / air ratio, both of which are used as safety indicators, have been described. However, the present invention is not limited to this, and any one of them may be used.

[Third Embodiment]
Hereinafter, a third embodiment of the present invention will be described.

  The configuration of the gas turbine 10 according to the third embodiment is the same as the configuration of the gas turbine 10 according to the first embodiment shown in FIGS.

The gas turbine 10 according to the third embodiment purges fuel (combustion remaining in the combustor 16 in the third embodiment) in order to start.
When purging, the compressor 14 is rotated using an electric motor controlled by a thyristor. The electric motor is the generator 30 connected to the turbine 12 and the compressor 14 as described above.

  Then, when purging the combustor 16, the purge rotational speed determination unit 44 according to the third embodiment sets the rotational speed of the compressor 14 according to the output of the thyristor (hereinafter referred to as “thyristor output”). decide. The larger the thyristor output, the faster the rotation speed of the compressor 14 and the shorter the purge time. Note that the maximum value of the thyristor output is determined for each gas turbine 10.

FIG. 8 is a graph showing the relationship between the thyristor output and the rotational speed, and FIG. 9 is a graph showing the relationship between the purge rotational speed and the purge time.
The thyristor output is a product of the voltage, current, and power factor of the thyristor as shown in the equation (1), and is the product of the torque and the rotational speed of the motor controlled by the thyristor.
Thyristor output (W) = Voltage x Current x Power factor = Torque x Number of revolutions (1)

As shown in FIG. 8, the power consumption of the compressor 14 increases as the rotational speed increases. The power consumption is the sum of the speed increasing power and the resistance power. Ascending power is obtained from inertia and rotational acceleration, and resistance power is obtained from frictional resistance or the like.
The larger the thyristor output, the more power can be consumed and the rotation speed of the compressor 14 can be increased.

  As shown in FIG. 9, when purging is performed, the faster the rotation speed of the compressor 14, the shorter the purge time. The purge time is the predetermined number of times of the air in the combustor 16 based on the capacity of the equipment to be purged, that is, the capacity of the combustor 16 in the third embodiment and the wind force obtained from the rotational speed of the compressor 14. It is calculated as the time required for replacement (for example, twice).

  FIG. 10 is a flowchart showing the flow of the gas turbine startup process executed by the control device 40 according to the third embodiment. In FIG. 10, the same steps as those in FIG. 6 are denoted by the same reference numerals as those in FIG.

  First, in step 100, the turbine 12 and the compressor 14 which are turbo machines are started, and the process proceeds to step 102 '.

  In step 102 ', the purge rotational speed is determined. In the third embodiment, the rotational speed of the compressor 14 corresponding to the thyristor output is determined as the purge rotational speed, and the routine proceeds to step 104.

  The purge rotation speed may be determined in advance according to the thyristor output, or may be calculated every time the gas turbine 10 is started.

FIG. 11 is a graph showing the relationship between the thyristor output and the rotational speed of the compressor 14 and the turbine 12 that are turbomachines.
As the gas turbine 10 is started, the thyristor output increases and the compressor 14 is rotated until the purge rotational speed is reached. Along with this, the turbine 12 also rotates to the purge rotational speed. When the rotational speed reaches the purge rotational speed, the thyristor output once decreases, but when the purge is completed and the combustor 16 is ignited, it rises again. This is because the thyristor output supports the increase in the rotational speed of the turbine 12 until the combustor 16 is ignited for a while. As an example, after the combustor 16 is ignited, the support by the thyristor output is performed until the rotation speed of the turbine 12 reaches 50% of the rated rotation speed, and then the support of the thyristor output is stopped. When the rotational speed of the turbine 12 reaches the rated rotational speed, the speed increase is terminated.

  As described above, the control device 40 of the gas turbine 10 according to the third embodiment is for rotating the compressor 14 by the electric motor controlled using the thyristor when purging the combustor 16. A purge rotational speed determination unit 44 that determines the rotational speed of the compressor 14 according to the output of the thyristor is provided. Therefore, the control device 40 of the gas turbine 10 according to the third embodiment can optimize the purge time according to the output of the thyristor.

  In addition, although the form which purges the combustor 16 was demonstrated in this 3rd Embodiment, this invention is not limited to this, Like a gas turbine combined cycle (Gas Turbine Combined Cycle: GTCC) plant An exhaust gas boiler that recovers heat from the exhaust gas exhausted from the gas turbine 10 may be provided, and the exhaust gas boiler may be purged together with the combustor 16.

  As mentioned above, although this invention was demonstrated using said each embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. Various changes or improvements can be added to the above-described embodiments without departing from the gist of the invention, and embodiments to which the changes or improvements are added are also included in the technical scope of the present invention.

  For example, in each of the above embodiments, when the gas turbine 10 is started up, the form in which the compressor 14 and the turbine 12 are accelerated using the generator 30 as an electric motor has been described. However, the present invention is limited to this. Instead of this, it is possible to provide a motor only for starting and to accelerate the compressor 14 and the turbine by the motor without using the generator 30 when starting the gas turbine 10.

  Further, in each of the above embodiments, the mode in which one control device 40 controls one gas turbine 10 has been described. However, the present invention is not limited to this, and one control device 40 has a plurality of gasses. The turbine 10 may be controlled. In the case of this embodiment, the control device 40 stores or calculates the safety index, combustion stability index, and thyristor output values corresponding to each gas turbine 10, and the rotational acceleration of the turbine 12 when starting the gas turbine 10. The ignition fuel / air ratio and the purge speed are obtained for each gas turbine 10.

  The flow of the gas turbine startup process described in each of the above embodiments is also an example, and unnecessary steps are deleted, new steps are added, or the processing order is changed within a range not departing from the gist of the present invention. Or you may.

DESCRIPTION OF SYMBOLS 10 Gas turbine 12 Turbine 14 Compressor 16 Combustor 30 Generator 40 Control apparatus 44 Purge rotation speed determination part 46 Ignition fuel / air ratio determination part 48 Rotational acceleration determination part 50 Acceleration fuel / air ratio determination part

Claims (7)

Compressor for generating compressed air by compressing air taken in from air intake port, combustor for generating combustion gas by burning fuel with compressed air, and gas turbine including turbine driven by the combustion gas A control device of
Rotational acceleration determining means for determining the maximum rotational acceleration that the turbine is capable of based on a first index indicating a relationship between damage of equipment constituting the gas turbine and rotational acceleration of the turbine;
Accelerating fuel / air ratio determining means for determining a fuel / air ratio of the combustor so that the turbine accelerates at the rotational acceleration determined by the rotational acceleration determining means;
A control device for a gas turbine.   The first index includes the relationship between the turbine blade contact with the casing and the rotational acceleration of the turbine, the surging of the compressor and the rotational acceleration of the turbine, and the exhaust gas temperature of the turbine and the turbine. The gas turbine control device according to claim 1, wherein the control device is at least one of a relationship with rotational acceleration.   Based on the second index indicating the relationship between the physical quantity related to fuel or air and the fuel-air ratio, which allows the fuel to be stably combusted by the combustor, the physical quantity and the fuel-air ratio in the case where the combustor is ignited. The gas turbine control device according to claim 1, further comprising ignition fuel / air ratio determination means for determining the ignition fuel / air ratio.   The second index indicates a region where no backfire or misfire occurs, a relationship between a fuel-air mixed gas or air jet velocity and a fuel-air ratio, and a region where no combustion vibration occurs, relative to the total fuel flow rate The gas turbine control device according to claim 3, wherein the control device is at least one of a relationship between a pilot ratio that is a ratio of a pilot fuel flow rate and a fuel-air ratio.   A rotational speed determining means for determining the rotational speed of the compressor according to the output of the thyristor in order to rotate the compressor by an electric motor controlled using the thyristor when purging the fuel; The control apparatus of the gas turbine in any one of Claims 1-4 provided. A compressor that generates compressed air by compressing air taken from the air intake;
A combustor that burns fuel with the compressed air and generates combustion gas;
A turbine driven by the combustion gas;
A control device according to any one of claims 1 to 5;
Gas turbine equipped with. Compressor for generating compressed air by compressing air taken in from air intake port, combustor for generating combustion gas by burning fuel with compressed air, and gas turbine including turbine driven by the combustion gas Control method,
A first step of determining a maximum rotational acceleration that the turbine is capable of based on a first index indicating a relationship between damage of equipment constituting the gas turbine and rotational acceleration of the turbine;
A second step of determining a fuel-air ratio of the combustor so that the turbine is accelerated at the determined rotational acceleration;
A method for controlling a gas turbine.

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