JP5185763B2 - Gas turbine and its operation method when stopped - Google Patents

Description

  The present invention relates to a gas turbine and an operation method when the gas turbine is stopped, and more particularly to prevention of catback when the gas turbine is stopped.

  A general gas turbine includes a compressor, a combustor, and a turbine, and air taken in from an air intake port is compressed by the compressor into high-temperature and high-pressure compressed air. This compressed air is supplied to a combustor, and in the combustor, fuel is supplied to the compressed air and burned to generate high-temperature and high-pressure combustion gas. Since this combustion gas drives the turbine connected to the compressor, for example, if a generator is connected to the output shaft side of the gas turbine, the generator can be driven by the gas turbine to generate electricity.

In such a gas turbine, an active clearance control (hereinafter referred to as ACC) system controls the tip clearance that fluctuates under the influence of temperature and centrifugal force that change according to the operating state to the minimum. It is intended to prevent interference between stationary parts and increase the efficiency of operation.
In general, in a gas turbine that does not control the tip clearance, the position where the tip clearance is minimized is not at the rated operation but at the start-up. Therefore, in the ACC system, the operating state that minimizes the tip clearance is set during rated operation by warming the stationary components that affect the tip clearance before starting the gas turbine. That is, as shown in FIG. 7, the ACC system warms the turbine stationary part before starting the gas turbine, widens the clearance in advance, and adjusts the temperature of the turbine stationary part during rated operation, thereby This is a technique to ensure the driving efficiency by realizing the minimum clearance.

By the way, the operation of the gas turbine by the ACC system described above can be roughly divided into the following five states.
(1) Immediately before start-up In order to perform the ACC system, the temperature adjustment medium is flowed to the stationary components on the turbine stationary blade side to warm it up, and the elongation is increased between the stationary portion such as the blade ring and the moving blade that is the rotating portion. Increase clearance.
(2) During startup (while increasing the load)
In order not to lose the clearance during startup (so that the stationary part and the rotating part do not come into contact with each other), the stationary system parts are kept warm in the same manner as immediately before the startup.
(3) During rated operation The clearance between the stationary part and the rotating part is minimized by changing the state (temperature, etc.) of the temperature adjustment medium flowing through the stationary system parts.
(4) Stopping (while lowering the load)
In order to prevent the clearance from being lost at the time of stopping (so that the stationary part and the rotating part do not come into contact with each other), the stationary parts are kept warm as before the start.
(5) When stopped In order to prevent catback, the high-temperature gas remaining inside the gas turbine is discharged outside the gas turbine. Further, in order to prevent catback, a temperature adjusting medium is passed through the stationary system parts to eliminate the distribution of gas remaining in the gas turbine.

  Thus, when stopping a gas turbine by an ACC system, the problem of a catback is pointed out. This catback is a phenomenon in which the gas turbine warps due to a temperature difference when the gas turbine is stopped. In other words, since the temperature inside the gas turbine is high during operation, temperature stratification occurs inside the gas turbine even after stopping, so there is a temperature difference between the gas turbine upper part (high temperature) and the gas turbine lower part (low temperature). It is formed. As a result, there is a difference in elongation between the upper part and the lower part of the gas turbine, so that the entire gas turbine is warped like a spine.

As a conventional technique for preventing such a catback, there is a technique in which a nozzle is provided at the upper part of the vehicle casing and the cooling air is flowed toward the upper part of the vehicle interior wall surface in order to reduce the temperature difference between the upper and lower sides. (For example, see Patent Document 1)
In addition, there is a type in which openings are provided in the lower part of the passenger compartment and the upper part of the passenger compartment, and air is circulated in the passenger compartment using a pump. (For example, see Patent Document 2)
JP 2005-171455 A JP 2002-371806 A

By the way, for example, a gas turbine that drives a generator performs DSS (Daily Start and Stop) operation in order to cope with fluctuations in power demand during daytime and nighttime. That is, in such DSS operation, since the operation and stop of the gas turbine are frequently performed, it is desirable to quickly complete the operation necessary for preventing the catback. Further, in the case of a gas turbine that performs DSS operation, it is desirable that the time required for startup is also short. Furthermore, it is desirable to minimize the incidental facilities necessary for preventing the catback.
The present invention has been made in view of the above circumstances, and the object of the present invention is to provide a gas turbine capable of promptly performing an operation necessary for preventing a catback when the gas turbine is stopped, and to stop the gas turbine. It is to provide a driving method when.

In order to solve the above problems, the present invention employs the following means.
A gas turbine according to the present invention is configured to obtain rotational power by supplying fuel to a compressed air compressed by a compressor and burning the fuel by a combustor and supplying the generated combustion gas to the turbine. In the turbine, connected to a branch flow path branched from the discharge side flow path of the compressor, a pressure increasing means capable of operating independently from the compressor for increasing the pressure by introducing a temperature adjusting medium, and the pressure increased by the pressure increasing means A temperature adjusting medium supply channel for guiding the increased temperature adjusting medium to a turbine cooling medium channel provided in a stationary system component of the turbine, and discharging the increased temperature adjusting medium that has passed through the turbine cooling medium channel. And a temperature adjustment medium return flow path that leads to the side flow path and joins, and is provided with a ventilation cooling system that operates the pressurizing means when the gas turbine is stopped and discharges the high-temperature gas remaining in the turbine. And it is characterized in that it is.

  According to such a gas turbine, the pressure increasing means connected to the branch flow path branched from the discharge side flow path of the compressor and capable of operating independently from the compressor for increasing the pressure by introducing the temperature adjustment medium, and the pressure increase The temperature adjustment medium supply flow path for guiding the pressure increase temperature adjustment medium boosted by the means to the turbine cooling medium flow path provided in the stationary system component of the turbine, and the pressure increase temperature adjustment medium passing through the turbine cooling medium flow path are discharged. A temperature adjustment medium return flow path that is led to the side flow path and merges, and is provided with a ventilation cooling system that operates the pressure increasing means when the gas turbine is stopped and discharges the high-temperature exhaust gas remaining in the turbine. When the engine is stopped, the hot gas remaining in the turbine is forcibly released into the atmosphere and quickly cooled by ventilation.

In the above invention, the ventilation / cooling system is branched from the temperature adjustment medium supply flow path and is provided with an exhaust flow path provided with flow path opening / closing means, and the temperature adjustment is downstream of the branch position of the exhaust flow path. It is preferable to include a channel opening / closing means provided in the medium supply channel.
In the above invention, the ventilation / cooling system preferably includes an exhaust passage exhaust passage that branches off from the branch passage and is provided with a passage opening / closing means.

  A gas turbine according to the present invention is configured to obtain rotational power by supplying fuel to a compressed air compressed by a compressor and burning the fuel by a combustor and supplying the generated combustion gas to the turbine. In the turbine, connected to a branch flow path branched from the discharge side flow path of the compressor, a pressure increasing means capable of operating independently from the compressor for increasing the pressure by introducing a temperature adjusting medium, and the pressure increased by the pressure increasing means A temperature adjusting medium supply channel for guiding the increased temperature adjusting medium to a turbine cooling medium channel provided in a stationary system component of the turbine, and discharging the increased temperature adjusting medium that has passed through the turbine cooling medium channel. A temperature adjustment medium return flow path that is led to the side flow path to be joined, operates the pressure increasing means when the gas turbine is stopped, and causes the pressure increase temperature adjustment medium to flow in the turbine cooling medium flow path It is characterized.

  According to such a gas turbine, the pressure increasing means connected to the branch flow path branched from the discharge side flow path of the compressor and capable of operating independently from the compressor for increasing the pressure by introducing the temperature adjustment medium, and the pressure increase The temperature adjustment medium supply flow path for guiding the pressure increase temperature adjustment medium boosted by the means to the turbine cooling medium flow path provided in the stationary system component of the turbine, and the pressure increase temperature adjustment medium passing through the turbine cooling medium flow path are discharged. A temperature adjusting medium return flow path that is led to the side flow path to be joined, and operates the pressure increasing means when the gas turbine is stopped and causes the pressure increasing temperature adjusting medium to flow in the turbine cooling medium flow path. The boosted temperature adjusting medium flows in the medium flow path so as to circulate, and the temperature distribution inside the gas turbine can be made substantially uniform.

  According to the gas turbine stop operation method of the present invention, fuel is supplied to the compressed air compressed by the compressor and burned, and the generated combustion gas is supplied to the turbine to obtain rotational power. A gas turbine stop operation method that is configured, wherein the gas turbine is connected to a branch flow path that branches from a discharge-side flow path of the compressor when the gas turbine is stopped, and can be operated independently from the compressor. A process in which the means introduces a temperature adjustment medium to increase the pressure, and the pressure increase temperature adjustment medium boosted by the pressure increase means is discharged through the temperature adjustment medium supply flow path, the turbine cooling medium flow path, and the temperature adjustment medium return flow path. And a process of returning to the side flow path and a process of passing through the combustor and the turbine from the discharge side flow path and exhausting to the atmosphere.

  According to such a gas turbine stop-time operation method, when the gas turbine is stopped, the pressure boosting means connected to the branch flow path branching from the discharge side flow path of the compressor and operable independently from the compressor has a temperature. The process of increasing the pressure by introducing the adjustment medium, and the pressure increase temperature adjustment medium boosted by the pressure increase means returns to the discharge side flow path via the temperature adjustment medium supply flow path, the turbine cooling medium flow path, and the temperature adjustment medium return flow path. And a process of exhausting air from the discharge side passage through the combustor and turbine to the atmosphere, so that when the gas turbine is stopped, the high-temperature gas remaining in the turbine is forcibly released to the atmosphere. And can be quickly ventilated and cooled.

  According to the gas turbine stop operation method of the present invention, fuel is supplied to the compressed air compressed by the compressor and burned, and the generated combustion gas is supplied to the turbine to obtain rotational power. A gas turbine stop operation method that is configured, wherein the gas turbine is connected to a branch flow path that branches from a discharge-side flow path of the compressor when the gas turbine is stopped, and can be operated independently from the compressor. A process in which the means introduces a temperature adjustment medium to increase the pressure, and the pressure increase temperature adjustment medium boosted by the pressure increase means is discharged through the temperature adjustment medium supply flow path, the turbine cooling medium flow path, and the temperature adjustment medium return flow path. A process of returning to the side flow path, and a process of sucking into the pressure increasing means from the discharge side flow path through the branch flow path.

  According to such a gas turbine stop-time operation method, when the gas turbine is stopped, the pressure boosting means connected to the branch flow path branching from the discharge side flow path of the compressor and operable independently from the compressor has a temperature. The process of increasing the pressure by introducing the adjustment medium, and the pressure increase temperature adjustment medium boosted by the pressure increase means returns to the discharge side flow path via the temperature adjustment medium supply flow path, the turbine cooling medium flow path, and the temperature adjustment medium return flow path. Process and a process of being sucked into the pressure boosting means from the discharge side flow path through the branch flow path, so that when the gas turbine is stopped, the flow of the pressure increase temperature adjusting medium circulates in the turbine cooling medium flow path, The temperature distribution inside the gas turbine can be made substantially uniform.

  According to the gas turbine stop operation method of the present invention, fuel is supplied to the compressed air compressed by the compressor and burned, and the generated combustion gas is supplied to the turbine to obtain rotational power. When the gas turbine is stopped and the gas turbine stop period is long when the gas turbine is stopped, the stop operation method according to claim 5 is selected and the gas turbine stop period is short. The stop operation method according to claim 6 is selected.

  According to such a gas turbine stop operation method, when the gas turbine is stopped, the stop operation method according to claim 5 is selected when the gas turbine stop period is long, and the gas turbine stop period is short. Since the operation method at the time of stop according to item 6 is selected, for example, when the gas turbine stop period is short as in the DSS operation, the inside of the turbine is heated to a relatively high temperature by selecting the operation method at stop. It is possible to maintain substantially uniform and shorten the warm-up operation time at startup.

According to the present invention described above, when the gas turbine is stopped, high temperature gas inside the turbine is released to the atmosphere, or the temperature distribution inside the turbine is kept substantially uniform, so that the operation operation necessary for preventing the catback is performed. It can be implemented reliably and promptly.
In particular, when the pressurized temperature adjustment medium is circulated in the turbine cooling medium flow path and the temperature distribution inside the turbine is kept substantially uniform, the gas turbine is frequently operated and stopped as in the DSS operation. Even in such a case, it is possible to quickly complete the operation necessary for preventing the catback, and to shorten the warm-up operation time at the start-up.

  Also, for the incidental equipment required for preventing the catback, if the boosting means is shared with the boosting boosting means used for closed cooling and effectively used, the addition of the incidental equipment is minimized, that is, Control of the ACC system capable of preventing catback without adding new equipment can be performed to stably shut down the gas turbine.

Hereinafter, an embodiment of a gas turbine and a startup control method thereof according to the present invention will be described with reference to the drawings.
<First Embodiment>
FIG. 1 is a schematic diagram showing a gas turbine according to the present embodiment, FIG. 2 is a sectional view showing a schematic configuration of the gas turbine, and FIG. 3 is a schematic configuration diagram showing a turbine portion of the gas turbine. In the illustrated embodiment, a gas turbine that generates electric power by driving a generator will be described. However, the present invention is not limited to this.

The illustrated gas turbine 10 includes a compressor 11, a combustor 12, and a turbine 13, and a generator 14 is connected to the turbine 13. This compressor 11 has an air intake 15 for taking in air, and a plurality of stationary blades 17 and moving blades 18 are alternately arranged in a compressor casing 16, and an extraction manifold 19 is provided on the outside thereof. It has been.
The combustor 12 is combustible by supplying fuel to the compressed air compressed by the compressor 11 and igniting it with a burner.
In the turbine 13, a plurality of stationary blades 21 and moving blades 22 are alternately arranged in a turbine casing 20.

  An exhaust chamber 23 is continuously provided in the turbine casing 20 of the turbine 13, and the exhaust chamber 23 has an exhaust diffuser 24 that is continuous with the turbine 13. A rotor (turbine shaft) 25 is positioned so as to pass through the center of the compressor 11, the combustor 12, the turbine 13, and the exhaust chamber 23, and the end on the compressor 11 side is freely rotatable by the bearing portion 26. On the other hand, the end portion on the exhaust chamber 23 side is rotatably supported by the bearing portion 27. A plurality of disk plates are fixed to the rotor 25, the rotor blades 18 and 22 are connected, and the drive shaft of the generator 14 is connected to the end on the exhaust chamber 23 side.

  Therefore, the air taken in from the air intake 15 of the compressor 11 passes through the plurality of stationary blades 17 and the moving blades 18 and is compressed to become high-temperature and high-pressure compressed air. A predetermined amount of fuel supplied to the fuel burns. The high-temperature and high-pressure combustion gas generated in the combustor 12 drives and rotates the rotor 25 by passing through the plurality of stationary blades 21 and the moving blades 22 constituting the turbine 13, and is connected to the rotor 25. While generating electric power by applying rotational power to the generated generator 14, the exhaust gas is converted into static pressure by the exhaust diffuser 24 in the exhaust chamber 23 and then released to the atmosphere.

As described above, the fuel is supplied to the compressed air compressed by the compressor 11 and burned by the combustor 12, and the generated combustion gas is supplied to the turbine 13 to obtain the rotational driving force. For example, as shown in FIG. 1, the turbine 10 is provided with a booster 40 that boosts the pressure by extracting a part of the compressed air compressed by the compressor 11 from the passenger compartment through the stopped compressor 11. It has been.
In FIG. 1, during startup for increasing the load to the rated operation, during rated operation and during the stop for decreasing the load until it stops, the compressed air compressed by the compressor 11 passes through the compressed air supply passage 28. The combustion gas supplied to the combustor 12 and generated in the combustor 12 is supplied to the turbine 13 through the discharge passage 29 in the casing. Reference numeral 30 in the drawing denotes a fuel supply flow path.

The pressure increasing device 40 is a pressure increasing means for increasing the pressure of air used as a temperature adjusting medium (heating medium or cooling medium) to be described later. For example, a compressor or a blower is used. The booster 40 is provided with a dedicated electric motor 41 and can be operated independently from the compressor 11 that boosts the pressure by introducing air. It is desirable that the booster 40 be shared with, for example, a compressor that supplies compressed air for cooling the combustor during rated operation or the like (a boost-up booster used for closed cooling).
The suction side of the booster 40 is connected to a branch passage 42 branched from a compressed air supply passage 28 formed in the vehicle interior, and the discharge side is connected to a temperature adjustment medium supply passage 43. The temperature adjustment medium supply flow path 43 is a flow path that guides the compressed air (pressure-increasing temperature adjustment medium) to the turbine cooling medium flow path 50 provided in the stationary system component of the turbine 13.

  For example, as shown in FIG. 3, the turbine cooling medium flow path 50 is a flow path that communicates the turbine casing 20, the stationary blade 21, and the blade ring 31, and particularly faces the tip of the rotor blade 22. It is used for temperature adjustment by cooling or heating by flowing compressed air through the blade ring 31 of the stationary part that is in position and affects the tip clearance. The blade ring 31 is a member attached to the turbine casing 20 so as to surround the outer peripheral side of the rotor blade 22.

That is, the turbine cooling medium flow path 50 has a structure in which the stationary blade 21 is cooled and the blade ring 31 is cooled by flowing compressed air having a relatively low temperature during the rated operation of the gas turbine 10. Become. Further, the turbine cooling medium flow path 50 heats the stationary blade 21 and the blade ring 31 by flowing compressed air having a relatively high temperature during preparation immediately before starting the gas turbine 10, and during startup and stoppage. It becomes a warming structure. Therefore, the turbine coolant flow path 50 can be used for cooling and heating of stationary components in the ACC system. In addition, the code | symbol 31a in a figure is the blade ring internal flow path provided over the perimeter of the blade ring 31. FIG.
The compressed air that has passed through the turbine cooling medium flow path 50 merges into the compressed air supply flow path 28 through the temperature adjustment medium return flow path 44, and then flows into the combustor 12 through the compressed air supply flow path 28. .

Therefore, the booster 40 is operated when the gas turbine 10 is stopped, so that the high-temperature gas remaining in the turbine 13 can be discharged to perform ventilation cooling. Hereinafter, a ventilation cooling system for ventilating and cooling the high-temperature gas inside the turbine 13 when the gas turbine 10 is stopped will be described.
When the gas turbine 10 is stopped, the compressor 11 connected to the turbine 13 is also stopped. Therefore, when the booster 40 capable of operating independently from the compressor 11 is started, the air sucked from the branch flow path 42 is absorbed. The pressure is increased to become compressed air, which flows out to the temperature adjusting medium flow path 43.

The compressed air flows into the compressed air supply flow path 28 through the temperature adjustment medium flow path 43, the turbine cooling medium flow path 50, and the temperature adjustment medium return flow path 44. The compressed air that has flowed into the compressed air supply channel 28 flows to the combustor 12 side.
The compressed air flowing to the combustor 12 side passes through the combustor 12 and the turbine 13 and is released to the atmosphere. At this time, the high-temperature gas remaining in the combustor 12 and the turbine 13 flows out to the atmosphere so as to be pushed out by the compressed air.

  Therefore, by operating the pressure booster 40 when the gas turbine 10 is stopped, the compressed air boosted by the pressure booster 40 forcibly releases the high-temperature gas remaining in the turbine to the atmosphere, and prompt ventilation cooling is performed. A ventilation cooling system is formed to do this. That is, the compressed air flowing through the ventilation cooling system flows out of the booster 40 and passes through the temperature adjustment medium flow path 43, the turbine cooling medium flow path 50, and the temperature adjustment medium return flow path 44, and further, the compressed air supply flow path 28. Is passed through the combustor 12 and the turbine 13 and released into the atmosphere, thereby ventilating and cooling the high-temperature gas remaining in the combustor 12 and the turbine 13.

In the gas turbine 10 of the present embodiment, when the gas turbine 10 is stopped, the inside of the gas turbine is ventilated and cooled by the following operation method to prevent catback.
That is, the branch flow path that branches from the compressed air supply flow path 28 of the compressor 10 in order to forcibly release the high-temperature gas remaining in the turbine 13 to the atmosphere when the gas turbine 10 is stopped and to quickly ventilate and cool it. 42, a process in which the booster 40 connected to the compressor 42 and operated independently from the compressor 10 introduces air to boost the pressure, and the compressed air boosted by the booster includes the temperature adjustment medium supply channel 43, the turbine cooling medium A process of returning to the compressed air supply flow path 28 through the flow path 50 and the temperature adjusting medium return flow path 44 and a process of exhausting the compressed air supply flow path 28 through the combustor 12 and the turbine 13 to the atmosphere. Yes.

Moreover, about the ventilation cooling system mentioned above, you may employ | adopt the modification as shown, for example in FIG.4 and FIG.5.
The ventilation cooling system of the first modification shown in FIG. 4 branches from the temperature adjustment medium supply flow path 43, and has an exhaust flow path 61 provided with a first on-off valve 60 of the flow path opening / closing means, and this exhaust flow. The temperature adjustment medium supply flow path 43 at a position downstream of the position where the path 61 branches is provided with a second open / close valve 62 provided as a flow path opening / closing means.

In the ventilation / cooling system configured as described above, when the booster 40 is started when the gas turbine 10 is stopped, the first on-off valve 60 is opened and the second on-off valve 62 is closed. When the gas turbine 10 is not stopped, the first on-off valve 60 is closed and the second on-off valve 62 is opened.
When the booster 40 is operated when the gas turbine 10 is stopped in the state described above, the compressed air boosted by the booster 40 is released from the exhaust passage 61 to the atmosphere. At this time, the suction side of the booster 40 has a negative pressure, and the high-temperature gas remaining in the turbine 13 is forcibly sucked and released to the atmosphere, so that quick ventilation cooling can be performed. That is, in the ventilation cooling system in this case, high-temperature gas flows back from the turbine 13 through the discharge passage 29, the combustor 12 and the compressed air supply passage 28 to the branch passage 42 and is boosted by the booster 40. After that, the gas is discharged from the temperature adjustment medium flow path 43 to the atmosphere through the exhaust flow path 61 with the first on-off valve 60 opened.

The ventilation cooling system of the second modified example shown in FIG. 5 includes an exhaust passage 64 that branches from the branch passage 42 and that is provided with a third on-off valve 63 that is a passage opening / closing means.
In the ventilation cooling system configured as described above, the third on-off valve 63 is opened when the booster 40 is started when the gas turbine 10 is stopped. Note that the third on-off valve 63 is closed except when the gas turbine 10 is stopped.

  When the booster 40 is operated when the gas turbine 10 is stopped in the above-described state, the compressed air boosted by the booster 40 passes through the inside of the turbine 13 and a high-temperature gas is sucked into the suction side of the booster 40. For this reason, the gas having a high temperature existing in the turbine 13 is forced out by the compressed air and sucked and discharged from the exhaust passage 64 to the atmosphere, so that quick ventilation cooling can be performed. At this time, the suction side of the booster 40 may be set to a negative pressure so that the high-temperature gas remaining in the turbine 13 is forcibly pushed out and sucked, or the booster 40 directly draws air from the atmosphere. By providing the suction system 45 for sucking in, the hot gas remaining in the turbine 13 may be forced out.

In this way, after the gas turbine 10 is stopped, when the high-temperature gas in the turbine 13 is released to the atmosphere and rapid ventilation cooling is performed, the temperature difference generated inside the turbine is alleviated or eliminated. Can be prevented.
In addition, for the incidental facilities necessary for preventing the above-described catback, by using the booster 40 and the like in common with the boosting means for boosting used for closed cooling, it is possible to perform the catback without adding new facilities. Prevention becomes possible.

<Second Embodiment>
Then, the gas turbine which concerns on this embodiment is demonstrated based on FIG. In addition, the same code | symbol is attached | subjected to the part similar to embodiment mentioned above, and the detailed description is abbreviate | omitted.
In the gas turbine 10 of this embodiment, the booster 40 is operated when the gas turbine 10 is stopped, and the compressed air (pressurized temperature adjusting medium) is caused to flow in the turbine cooling medium flow path 50. That is, unlike the first embodiment in which the inside of the turbine 13 is actively ventilated and cooled, the compressed air (for example, by closing the air intake 15 of the compressor 11 or the exhaust side of the turbine 13 as necessary). The high temperature gas is circulated through the turbine cooling flow path 50 to make the temperature distribution uniform.

That is, by the operation of the booster 40, high-temperature gas (temperature adjustment medium) existing inside the combustor 12 and the turbine 13 is sucked and pressurized to become compressed air that functions as a boosted temperature adjustment medium. After the compressed air flows out to the temperature adjustment medium flow path 43, it passes through the turbine cooling medium flow path 50, the temperature adjustment medium return flow path 44, the compressed air supply flow path 28, and the branch flow path 42, and is sucked into the booster 40. Is done. As a result, the compressed air circulates through the closed circuit flow path.
The compressed air that circulates in this way flows through the blade ring inner passage 31a formed in the blade ring 31 when passing through the turbine cooling medium flow 50, so that the periphery of the turbine casing 20 is substantially uniform over the entire circumference. It becomes temperature distribution. For this reason, a temperature difference due to convection hardly occurs in the interior of the turbine 13 and the entire temperature distribution becomes substantially uniform, so that catback can be prevented.

  In addition, when the compressed air boosted by the booster 40 is circulated, the temperature is lowered due to heat radiation from the turbine casing 20, but the compressed air whose temperature has been increased by the boost is circulated, thereby reducing the internal temperature of the turbine 13. It can be kept at a relatively high temperature. As a result, for example, in the gas turbine 10 that performs the DSS operation, the temperature decrease that occurs between the time when the gas turbine 10 is stopped and the time when the operation is restarted can be minimized. Can be shortened.

In the gas turbine 10 of the present embodiment, when the gas turbine 10 is stopped, the inside of the gas turbine is ventilated and cooled by the following operation method to prevent catback.
That is, the gas turbine stop operation method of the present invention is connected to the branch passage 42 branched from the compressed air supply passage 28 of the compressor 11, and the booster 40 that can be operated independently from the compressor 11 supplies the air. The process of introducing and increasing the pressure, and the compressed air pressurized by the pressure increasing device 40 to the compressed air supply flow path 28 through the temperature adjustment medium supply flow path 43, the turbine cooling medium flow path 50 and the temperature adjustment medium return flow path 44. A process of returning, and a process of sucking into the booster 40 from the compressed air supply flow path 28 through the branch flow path 42.

Accordingly, when the gas turbine 10 is stopped, the compressed air flows so as to circulate in the turbine cooling medium flow path 50, and this flow extends over the entire circumference of the turbine casing 20. Is substantially uniform.
And about the operation method at the time of stop which performs ventilation cooling demonstrated in 1st Embodiment mentioned above, and the operation method at the time of stop which performs equalization of temperature distribution by compressed air circulation demonstrated in this embodiment, of gas turbine 10 It is desirable to use properly considering the suspension period.

Specifically, when the gas turbine stop period is long, a stop operation method for performing ventilation cooling is selected, and when the gas turbine stop period is short, a stop operation method using compressed air circulation may be selected.
By making such a selection, for example, when the gas turbine stop period is short, such as DSS operation, and restarted after a short stop, the period between the stop and the restart of the operation Since the temperature drop which arises can be suppressed to the minimum, the time of warm-up operation required at the time of restart can be shortened. That is, it is possible to perform a smooth and efficient DSS operation while preventing catback.

  As described above, according to the present invention described above, when the gas turbine 10 is stopped, the high-temperature gas in the turbine 13 is released into the atmosphere, or the temperature distribution in the turbine 13 is kept substantially uniform. The driving operation necessary for preventing the catback can be carried out reliably and promptly. In particular, when the compressed air is circulated in the turbine cooling medium flow path 50 and the temperature distribution in the turbine 13 is kept substantially uniform, the gas turbine is frequently operated and stopped as in the DSS operation. Even in such a case, it is possible to quickly complete the operation necessary for preventing the catback, and to shorten the warm-up operation time at the start-up.

In addition, with regard to incidental equipment necessary for preventing the catback, if the booster 40 and the like are shared with the boosting means for boosting used for closed cooling and effectively used, the addition of the incidental equipment is minimized, that is, The stable operation of the gas turbine 10 can be stopped by controlling the ACC system capable of preventing the catback without adding new equipment.
In addition, this invention is not limited to embodiment mentioned above, For example, it can change suitably in the range which does not deviate from the summary of this invention about the connection form etc. of a compressor and a turbine.

1 is a schematic diagram showing a gas turbine according to a first embodiment of the present invention. It is a schematic block diagram which shows the structural example of a gas turbine. It is explanatory drawing of the turbine cooling medium flow path provided in the stationary system components of a turbine. It is the schematic which shows the 1st modification based on 1st Embodiment shown in FIG. It is the schematic which shows the 2nd modification which concerns on 1st Embodiment shown in FIG. It is the schematic which shows the gas turbine which concerns on the 2nd Embodiment of this invention. It is explanatory drawing of an ACC system, (a) is the relationship between time and rotation speed / load, (b) is the relationship between time and temperature, (c) is the relationship between time and elongation, (d) is time and The relationship with clearance is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Gas turbine 11 Compressor 12 Combustor 13 Turbine 20 Turbine casing 21 Stator blade 22 Moving blade 28 Compressed air supply flow path 29 Discharge flow path 31 Blade ring 40 Booster device 42 Branch flow path 43 Temperature adjustment medium supply flow path 44 Temperature Adjustment medium return flow path 50 Turbine cooling medium flow path 61, 64 Exhaust flow path

Claims (7)

In a gas turbine configured to obtain rotational power by supplying fuel to a compressed air compressed by a compressor and burning it by a combustor and supplying the generated combustion gas to the turbine,
A booster connected to a branch channel branched from the discharge-side channel of the compressor and capable of operating independently from the compressor for boosting pressure by introducing a temperature adjusting medium, and a boosted temperature boosted by the booster A temperature adjustment medium supply flow path that guides the adjustment medium to a turbine cooling medium flow path provided in a stationary system component of the turbine, and a discharge side flow path that passes the boosted temperature adjustment medium that has passed through the turbine cooling medium flow path A temperature adjusting medium return flow path that is led to join and
A gas turbine characterized in that a ventilation cooling system is provided that operates the pressure-increasing means when the gas turbine is stopped and discharges the high-temperature gas remaining in the turbine.   The ventilation cooling system includes an exhaust passage that is branched from the temperature adjustment medium supply passage and provided with a passage opening and closing means, and the temperature adjustment medium supply passage that is downstream from the branch position of the exhaust passage. The gas turbine according to claim 1, further comprising a flow path opening / closing means provided.   2. The gas turbine according to claim 1, wherein the ventilation cooling system includes an exhaust flow path exhaust flow path branched from the branch flow path and provided with flow path opening / closing means. In a gas turbine configured to obtain rotational power by supplying fuel to a compressed air compressed by a compressor and burning it by a combustor and supplying the generated combustion gas to the turbine,
A booster connected to a branch channel branched from the discharge-side channel of the compressor and capable of operating independently from the compressor for boosting pressure by introducing a temperature adjusting medium, and a boosted temperature boosted by the booster A temperature adjustment medium supply flow path that guides the adjustment medium to a turbine cooling medium flow path provided in a stationary system component of the turbine, and a discharge side flow path that passes the boosted temperature adjustment medium that has passed through the turbine cooling medium flow path A temperature adjusting medium return flow path that is led to join and
A gas turbine characterized in that the pressure-increasing means is operated when the gas turbine is stopped, and the pressure-rising temperature adjusting medium is caused to flow in the turbine cooling medium flow path. This is a gas turbine stop operation method configured to obtain rotational power by supplying fuel to compressed air compressed by a compressor and burning it with a combustor and supplying the generated combustion gas to the turbine. And
When the gas turbine stops
A process in which a pressure increasing means connected to a branch flow path branched from the discharge side flow path of the compressor and capable of operating independently from the compressor introduces a temperature adjusting medium to increase the pressure;
A process in which the boosted temperature adjusting medium boosted by the boosting means returns to the discharge-side flow path via a temperature adjusting medium supply flow path, a turbine cooling medium flow path, and a temperature adjustment medium return flow path;
And a process of exhausting the combustor and the turbine from the discharge side passage to the atmosphere. This is a gas turbine stop operation method configured to obtain rotational power by supplying fuel to compressed air compressed by a compressor and burning it with a combustor and supplying the generated combustion gas to the turbine. And
When the gas turbine stops
A process in which a pressure increasing means connected to a branch flow path branched from the discharge side flow path of the compressor and capable of operating independently from the compressor introduces a temperature adjusting medium to increase the pressure;
A process in which the boosted temperature adjusting medium boosted by the boosting means returns to the discharge-side flow path via a temperature adjusting medium supply flow path, a turbine cooling medium flow path, and a temperature adjustment medium return flow path;
And a step of sucking into the pressure-increasing means from the discharge side passage through the branch passage. This is a gas turbine stop operation method configured to obtain rotational power by supplying fuel to compressed air compressed by a compressor and burning it with a combustor and supplying the generated combustion gas to the turbine. And
When the gas turbine is stopped, when the gas turbine stop period is long, the stop operation method according to claim 5 is selected, and when the gas turbine stop period is short, the stop operation method according to claim 6 is selected. The operation method when the gas turbine is stopped.

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