Gas turbine apparatus and manufacturing method for the same, and operation method for gas turbine apparatus

1. A gas turbine apparatus, comprising:

a turbine configured to be driven by a combustion gas from a combustor;

an exhaust passage configured to allow exhaust air from the turbine to flow;

an extraction line configured to extract a fluid from a combustor casing;

a cooling part disposed in the extraction line and configured to cool the fluid;

a return line for returning the fluid from the cooling part to an inside of the combustor casing, the return line being connected to the extraction line downstream of the cooling part;

a bypass line for introducing the fluid from the cooling part to the exhaust passage by bypassing the turbine, the bypass line branching from the return line; and

at least one valve capable of controlling at least one of a communication state between the extraction line and the combustor casing via the return line, or a communication state between the extraction line and the exhaust passage via the bypass line,

wherein the at least one valve is configured to:

during an operation of the gas turbine apparatus at a first load, cause the extraction line and the combustor casing to communicate with each other via the return line, and shut off communication between the extraction line and the exhaust passage via the bypass line; and

during an operation of the gas turbine apparatus at a second load which is lower than the first load, shut off communication between the extraction line and the combustor casing via the return line, and cause the extraction line and the exhaust passage to communicate with each other via the bypass line,

wherein the gas turbine apparatus comprises a filter part for collecting foreign substances included in the fluid from the combustor casing, the filter part being disposed in the extraction line downstream of the cooling part,

wherein the extraction line communicates with a cooling target part of the turbine downstream of the filter part and is configured such that the fluid having foreign substances removed by the filter part is introduced to the extraction line downstream of the filter part, and

wherein the return line is connected to a foreign substance collection space of the filter part disposed in the extraction line and is configured such that the fluid containing the foreign substances collected in the foreign substance collection space is introduced to the return line.

2. The gas turbine apparatus according to claim 1 , comprising a control device for controlling opening and closing of the at least one valve,

wherein the at least one valve includes:

a return valve disposed downstream of a branch position of the bypass line in the return line, the return valve being capable of switching the communication state between the extraction line and the combustor casing via the return line; and

a bypass valve disposed in the bypass line, and capable of switching the communication state between the extraction line and the exhaust passage via the bypass line, and

wherein the control device is configured to:

during the operation of the gas turbine apparatus at the first load, open the return valve and close the bypass valve; and

during the operation of the gas turbine apparatus at the second load, close the return valve and open the bypass valve.

3. The gas turbine apparatus according to claim 1 ,

wherein the at least one valve includes a three-way valve disposed at a branch position of the bypass line in the return line, the three-way valve being capable of switching the communication state between the extraction line and the combustor casing via the return line, and the communication state between the extraction line and the exhaust passage via the bypass line.

4. The gas turbine apparatus according to claim 1 , further comprising a discharge line for introducing the fluid from the cooling part to the exhaust passage by bypassing the turbine, the discharge line branching from the return line or the bypass line.

5. The gas turbine apparatus according to claim 4 ,

wherein a diameter of a pipe forming the bypass line is larger than a diameter of a pipe forming the discharge line.

6. The gas turbine apparatus according to claim 1 ,

wherein the at least one valve is configured to, at a time of a transition from the operation at the first load to the operation at the second load, shut off the communication between the extraction line and the combustor casing via the return line, and then to cause the extraction line and the exhaust passage to communicate with each other via the bypass line.

7. The gas turbine apparatus according to claim 1 , comprising a control device for controlling the operation of the gas turbine apparatus,

wherein the control device is configured to, during the operation of the gas turbine apparatus at the first load, if an abnormality occurs such that it is impossible to cause the extraction line and the combustor casing to communicate with each other via the return line, control opening and closing of the at least one valve so as to cause the extraction line and the exhaust passage to communicate with each other via the bypass line and to cause the gas turbine apparatus to transition to the operation at the second load.

8. The gas turbine apparatus according to claim 1 , comprising a control device for controlling the operation of the gas turbine apparatus,

wherein the control device is configured to, during the operation of the gas turbine apparatus at the first load, if an abnormality occurs such that it is impossible to shut off the communication between the extraction line and the exhaust passage via the bypass line, cause the gas turbine apparatus to transition to the operation at the second load.

9. The gas turbine apparatus according to claim 1 , comprising a control device for controlling the operation of the gas turbine apparatus,

wherein the control device is configured to, during the operation of the gas turbine apparatus at the second load, if an abnormality occurs such that it is impossible to shut off the communication between the extraction line and the combustor casing via the return line, output a warning signal.

10. The gas turbine apparatus according to claim 1 , comprising a control device for controlling the operation of the gas turbine apparatus,

wherein the control device is configured to, during the operation of the gas turbine apparatus at the second load, if an abnormality occurs such that it is impossible to cause the extraction line and the exhaust passage to communicate with each other via the bypass line, control opening and closing of the at least one valve so as to cause the extraction line and the combustor casing to communicate with each other via the return line and to output a warning signal.

11. The gas turbine apparatus according to claim 1 , further comprising a compressor for generating a compressed fluid to be supplied to the combustor,

wherein the gas turbine apparatus is configured to, during the operation of the gas turbine apparatus at the second load, decrease an opening degree of an inlet guide vane of the compressor, as compared with during the operation at the first load.

12. An operation method for the gas turbine apparatus according to claim 1 ,

the method comprising:

during the operation of the gas turbine apparatus at the first load, a step of operating the gas turbine apparatus in the communication state in which the extraction line and the combustor casing are caused to communicate with each other via the return line, and the communication between the extraction line and the exhaust passage via the bypass line is shut off; and

a step of shutting off the communication between the extraction line and the combustor casing via the return line, and causing the extraction line and the exhaust passage to communicate with each other via the bypass line, at a time of switching from the operation of the gas turbine apparatus at the first load to the operation at the second load which is lower than the first load.

13. A manufacturing method for a gas turbine apparatus including:

a turbine configured to be driven by a combustion gas from a combustor;

an exhaust passage configured to allow exhaust air from the turbine to flow;

an extraction line configured to extract a fluid from a combustor casing;

a cooling part disposed in the extraction line and configured to cool the fluid;

a return line for returning the fluid from the cooling part to an inside of the combustor casing, the return line being connected to the extraction line downstream of the cooling part;

a bypass line for introducing the fluid from the cooling part to the exhaust passage by bypassing the turbine, the bypass line branching from the return line;

at least one valve capable of controlling at least one of a communication state between the extraction line and the combustor casing via the return line, or a communication state between the extraction line and the exhaust passage via the bypass line; and

a filter part for collecting foreign substances included in the fluid from the combustor casing, the filter part being disposed in the extraction line downstream of the cooling part,

wherein the extraction line communicates with a cooling target part of the turbine downstream of the filter part and is configured such that the fluid having foreign substances removed by the filter part is introduced to the extraction line downstream of the filter part, and

wherein the return line is connected to a foreign substance collection space of the filter part disposed in the extraction line and is configured such that the fluid containing the foreign substances collected in the foreign substance collection space is introduced to the return line,

the method comprising a step of connecting an upstream end of the bypass line to the return line or another line communicating with the return line to form the bypass line.