Patent Publication Number: US-2022235703-A1

Title: Gas turbine and control method thereof, and combined cycle plant

Description:
FIELD 
     The present invention relates to a gas turbine, a control method of the gas turbine, and a combined cycle plant including the gas turbine. 
     BACKGROUND 
     A gas turbine includes a compressor, a combustor, and a turbine. The compressor compresses air taken from an air intake to produce high-temperature and high-pressure compressed air. The combustor supplies fuel to the compressed air and combusts the mixture to generate high-temperature and high-pressure combustion gas. The turbine is driven by the combustion gas to drive a generator coaxially coupled to the turbine. 
     In a power-generating plant using a gas turbine, it is desired to enable high-efficiency operation not only in rated load operation but also in partial load operation. The output characteristics of the gas turbine fluctuate depending on an intake temperature. Therefore, in a case in which an output of the gas turbine is required to be reduced, the output can be reduced by an increase in the intake temperature without operating the gas turbine with a partial load. In addition, in the gas turbine operated with a partial load, fuel consumption can be minimized while complying with discharge regulations by a turndown range being widened. Examples of intake heating devices for such a gas turbine are described in the following Patent Literatures. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: Japanese Patent Application Laid-open No. 2013-160227 
     Patent Literature 2: Japanese Patent Application Laid-open No. 2017-155736 
     SUMMARY 
     Technical Problem 
     The compressor compresses air taken into the compressor to generate compressed air. The intake heating device of the conventional gas turbine described above increases the temperature of air to be taken into the compressor by heating the air with steam or the like generated by a heat recovery steam generator. In this case, the air to be taken into the compressor fluctuates depending on weather and seasons. Therefore, the temperature of the air to be taken into the compressor varies, and it is difficult to adjust the output of the gas turbine to a desired output. 
     The present invention is to solve the above-described problems, and an object of the present invention is to provide a gas turbine capable of adjusting an output of the gas turbine with high accuracy and a control method thereof, and a combined cycle plant. 
     Solution to Problem 
     In order to achieve the object described above, a gas turbine according to the present invention includes a compressor that compresses air; a combustor that mixes and combusts the compressed air compressed by the compressor and fuel; a turbine that obtains rotational power using combustion gas generated by the combustor; a compressed air cooling heat exchanger that cools the compressed air to produce air for heat exchange; an air temperature adjusting heat exchanger that exchanges heat between the compressed air and the air to be supplied to the compressor; a heat exchange amount adjusting device that adjusts a heat exchange amount of each of the compressed air cooling heat exchanger and the air temperature adjusting heat exchanger; and a control device that controls the heat exchange amount adjusting device. The control device controls the heat exchange amount adjusting device based on a temperature of the air to be taken into the compressor. 
     Therefore, the air temperature adjusting heat exchanger exchanges heat between the air and the compressed air, so that the air is heated with the compressed air, and the air whose temperature has increased by heating is taken into the compressor. In this case, the control device adjusts the heat exchange amount of the air temperature adjusting heat exchanger by the heat exchange amount adjusting device based on the temperature of the air to be taken into the compressor. That is, in a case in which the heat exchange amount of the air temperature adjusting heat exchanger is adjusted, a temperature of the air heated with the compressed air is adjusted. Here, since an output of the gas turbine changes depending on the temperature of the air to be taken into the compressor, the output of the gas turbine can be adjusted to a target output with high accuracy regardless of a load of the gas turbine. 
     In the gas turbine according to the present invention, a first temperature sensor that measures a temperature of the air heat-exchanged by the air temperature adjusting heat exchanger is provided, and the control device controls the heat exchange amount in the air temperature adjusting heat exchanger by the heat exchange amount adjusting device so that the temperature of the air measured by the first temperature sensor approaches a target temperature. 
     Therefore, since the control device controls the heat exchange amount in the air temperature adjusting heat exchanger by the heat exchange amount adjusting device so that the temperature of the air heat-exchanged by the air temperature adjusting heat exchanger approaches the target temperature, the temperature of the air to be taken into the compressor can be controlled with high accuracy. 
     In the gas turbine according to the present invention, a second temperature sensor that measures a temperature of the compressed air cooled by the compressed air cooling heat exchanger is provided, and the control device controls the heat exchange amount in the compressed air cooling heat exchanger by the heat exchange amount adjusting device so that the temperature of the compressed air measured by the second temperature sensor is maintained at a target temperature. 
     Therefore, since the control device controls the heat exchange amount in the compressed air cooling heat exchanger by the heat exchange amount adjusting device so that the temperature of the compressed air cooled with the compressed air cooling heat exchanger is maintained at a target temperature, the temperature of the air for heat exchange to be supplied to the turbine can be controlled with high accuracy. 
     In the gas turbine according to the present invention, the air temperature adjusting heat exchanger includes a first heat exchanger that exchanges heat between the air and a first medium, and a second heat exchanger that exchanges heat between the compressed air and the first medium, and the heat exchange amount adjusting device adjusts a heat exchange amount in the second heat exchanger. 
     Therefore, the second heat exchanger exchanges heat between the compressed air and the first medium to heat the first medium with the compressed air, the first heat exchanger exchanges heat between the air and the first medium to heat the air with the first medium, and the air whose temperature has increased by heating is taken into the compressor. In this case, the control device controls the heat exchange amount adjusting device based on the temperature of the air to be taken into the compressor to adjust the heat exchange amount in the second heat exchanger. That is, the amount of heat of the compressed air is adjusted to increase the temperature of the air through the first medium, and the temperature of the air to be taken into the compressor can be controlled with high accuracy. 
     In the gas turbine according to the present invention, a first cooling air supply line and a second cooling air supply line that supply the compressed air compressed by the compressor to the turbine as cooling air are provided in parallel, the second heat exchanger is provided in the first cooling air supply line, the compressed air cooling heat exchanger that exchanges heat between the compressed air and a second medium is provided in the second cooling air supply line, and a flow rate adjusting valve is provided as the heat exchange amount adjusting device in at least one of the first cooling air supply line and the second cooling air supply line. 
     Therefore, an opening degree of the flow rate adjusting valve is adjusted to adjust a flow rate of the compressed air flowing through the first cooling air supply line, so that the amount of heat supplied from the compressed air to the first medium can be adjusted by the second heat exchanger provided in the first cooling air supply line, and the temperature of the air to be taken into the compressor can be adjusted by the first medium with high accuracy. 
     In the gas turbine according to the present invention, a cooling air supply line that supplies the compressed air compressed by the compressor to the turbine as cooling air is provided, the second heat exchanger and the compressed air cooling heat exchanger that exchanges heat between the compressed air and a second medium are provided in the cooling air supply line in series, and a flow rate adjusting valve is provided as the heat exchange amount adjusting device in a first medium circulation line through which the first medium circulates between the first heat exchanger and the second heat exchanger. 
     Therefore, an opening degree of the flow rate adjusting valve is adjusted to adjust a flow rate of the first medium flowing through the first medium circulation line, so that the amount of heat supplied from the compressed air to the first medium can be adjusted by the second heat exchanger provided in the cooling air supply line, and the temperature of the air to be taken into the compressor can be adjusted by the first medium with high accuracy. 
     In the has turbine according to the present invention, the second medium is air or water. 
     Therefore, since air or water is used as the second medium and a material existing in the vicinity is used, it is possible to shorten a length of a pipe to be used, achieve the miniaturization of equipment, and suppress the increase in cost. 
     In the gas turbine according to the present invention, the compressed air cooling heat exchanger is provided in a first medium circulation line through which the first medium circulates between the first heat exchanger and the second heat exchanger. 
     Therefore, the compressed air cooling heat exchanger is provided in the first medium circulation line, so that the compressed air cooling heat exchanger, the first heat exchanger, and the second heat exchanger are disposed in the first medium circulation line, which enables the device to be compact. 
     In the gas turbine according to the present invention, the compressed air cooling heat exchanger is a cooling tower. 
     Therefore, the compressed air cooling heat exchanger is used as the cooling tower, so that the structure can be simplified. 
     In the has turbine according to the present invention, the heat exchange amount adjusting device includes an air bypass line that bypasses the air temperature adjusting heat exchanger to supply the air to the compressor, and a flow rate adjusting valve provided in the air bypass line. 
     Therefore, in a case in which it is not necessary to adjust the temperature of the air to be taken into the compressor, the air can be supplied from the air bypass line to the compressor by the flow rate adjusting valve without the air passing through the air temperature adjusting heat exchanger. 
     In the gas turbine according to the present invention, the air temperature adjusting heat exchanger includes a first heat exchanger that exchanges heat between the air and the compressed air, and a second heat exchanger that exchanges heat between the compressed air and a third medium, and the heat exchange amount adjusting device adjusts a heat exchange amount in the second heat exchanger. 
     Therefore, the second heat exchanger exchanges heat between the compressed air and the third medium to adjust the temperature of the compressed air by the third medium, the first heat exchanger exchanges heat between the air and the compressed air to heat the air with the compressed air, and the air whose temperature has increased by heating is taken into the compressor. At this time, the control device controls the heat exchange amount adjusting device based on the temperature of the air to be taken into the compressor to adjust the heat exchange amount in the second heat exchanger. That is, the amount of heat of the compressed air is adjusted, so that the temperature of the air to be taken into the compressor can be controlled with high accuracy. 
     Further, a control method according to the present invention is of a gas turbine that includes a compressor that compresses air, a combustor that mixes and combusts the compressed air compressed by the compressor and fuel, and a turbine that obtains rotational power using combustion gas generated by the combustor. The control method includes the steps of: cooing the compressed air; increasing a temperature of the air by an amount of heat recovered by cooling the compressed air; and adjusting the amount of heat of the compressed air that increases a temperature of the air based on a temperature of the air to be taken into the compressor. 
     Therefore, in a case in which the amount of heat of the compressed air is adjusted, a temperature of the air heated with the compressed air is adjusted. Here, since an output of the gas turbine changes depending on the temperature of the air to be taken into the compressor, the output of the gas turbine can be adjusted to a target output with high accuracy regardless of a load of the gas turbine. 
     Further, a combined cycle plant according to the present invention includes the above-mentioned gas turbine; a heat recovery steam generator that generates steam by exhausted heat of flue gas discharged from the gas turbine; and a steam turbine including a turbine driven by steam generated by the heat recovery steam generator. 
     Therefore, since an output of the gas turbine charges depending on the temperature of the air to be taken into the compressor, the output of the gas turbine can be adjusted to a target output with high accuracy regardless of a load of the gas turbine, and an operation region in the combined cycle plant can be expanded. 
     Advantageous Effects of Invention 
     According to the gas turbine and the control method thereof, and the combined cycle plant of the present invention, the output of the gas turbine can be adjusted with high accuracy. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic configuration diagram illustrating a gas turbine of a first embodiment. 
         FIG. 2  is a graph illustrating a as turbine output with respect to an intake temperature of the gas turbine. 
         FIG. 3  is a schematic configuration diagram illustrating a combined plant of a second embodiment. 
         FIG. 4  is a schematic configuration diagram illustrating a combined plant of a third embodiment. 
         FIG. 5  is a schematic configuration diagram illustrating a gas turbine of a fourth embodiment. 
         FIG. 6  is a schematic configuration diagram illustrating a combined plant of a fifth embodiment. 
         FIG. 7  is a schematic configuration diagram illustrating a gas turbine of a sixth embodiment. 
         FIG. 8  is a schematic configuration diagram illustrating a gas turbine of a seventh embodiment. 
         FIG. 9  is a schematic configuration diagram illustrating a gas turbine of an eighth embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinafter, preferred embodiments of a gas turbine and a control method thereof, and a combined cycle plant according to the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to this embodiment, and in a case in which there are a plurality of embodiments, the present invention also includes configurations in which the embodiments are combined with each other. 
     First Embodiment 
       FIG. 1  is a schematic configuration diagram illustrating a gas turbine of a first embodiment. 
     In the first embodiment, as illustrated in  FIG. 1 , a gas turbine  10  includes a compressor  11 , a combustor  12 , a turbine  13 , and a control device  14 . 
     The compressor  11  and the turbine  13  are integrally rotatably coupled with a rotating shaft  21 , and a generator  22  is coupled to the rotating shaft  21 . The compressor  11  compresses air A flowing from an air intake line L 1 . The combustor  12  mixes and combusts compressed air CA supplied from the compressor  11  through a compressed air supply line L 2  and fuel F supplied from a fuel gas supply line L 3 . The turbine  13  is rotationally driven by combustion gas CG supplied from the combustor  12  through a combustion gas supply line L 4 . The generator  22  is driven by a rotational power transmitted by the rotation of the turbine  13 . In addition, a flue gas discharge line L 5  that discharges flue gas EG is coupled to the turbine  13 . 
     Therefore, during the operation of the gas turbine  10 , the compressor  11  compresses the air A, and the combustor  12  mixes and combusts the supplied compressed air CA and the fuel F. The turbine  13  is rotationally driven by the combustion gas CG supplied from the combustor  12 , and the generator  22  generates electricity. The gas turbine  10  (turbine  13 ) discharges the flue gas EG. 
     In addition, the gas turbine  10  includes a first heat exchanger (for example, an intake air heater)  31 , a second heat exchanger  32 , a third heat exchanger  33 , a first flow rate adjusting valve (heat exchange amount adjusting device)  34 , and a second flow rate adjusting valve (heat exchange amount adjusting device)  35 . In the first embodiment, the first heat exchanger  31  and the second heat exchanger  32  correspond to the air temperature adjusting heat exchanger of the present invention, and the third heat exchanger  33  corresponds to the compressed air cooling heat exchanger. In the first embodiment, heat is indirectly exchanged between the air A to be taken into the compressor  11  and the compressed air CA generated by the compressor  11  through a first medium. 
     The first heat exchanger  31  is provided in the air intake line L 1 . The first heat exchanger  31  exchanges heat between the air A taken from the air intake line L 1  and the first medium (for example, hot water) HW. That is, the air A flowing through the air intake line L 1  is heated with the first medium (for example, water) HW by the first heat exchanger  31  and then taken into the compressor  11 . 
     A first cooling air supply line L 11  and a second cooling air supply line L 12  are provided in parallel between the compressor  11  and the turbine  13 . The first cooling air supply line L 11  and the second cooling air supply line L 12  supplies part of the compressed air CA compressed by the compressor  11  to the turbine  13  as cooling air. One end portion of the first cooling air supply line L 11  and one end portion of the second cooling air supply line L 12  are joined together and coupled to a combustor casing chamber (not illustrated) of the compressor  11 . The other end portions thereof are joined together and coupled to a high temperature portion of the turbine  13 . 
     The second heat exchanger  32  is provided in the first cooling air supply line L 11 , and the third heat exchanger  33  is provided in the second cooling air supply line L 12 . In addition, a first flow rate adjusting valve  34  is provided on an upstream side of the second heat exchanger  32  in the first cooling air supply line L 11 . A second flow rate adjusting valve  35  is provided on an upstream side of the third heat exchanger  33  in the second cooling air supply line L 12 . 
     A first medium circulation line L 13  is provided between the first heat exchanger  31  and the second heat exchanger  32 . A circulation pump  41  is provided in the first medium circulation line L 13 . Therefore, the circulation pump  41  can be driven to circulate the first medium HW between the first heat exchanger  31  and the second heat exchanger  32  through the first medium circulation line L 13 . Then, the first medium HW circulating through the first medium circulation line L 13  is heated with the compressed air CA 1  in the second heat exchanger  32 , which flows through the first cooling air supply line L 11 , to heat the air A in the first heat exchanger  31 , which flows through the air intake line L 1 . Here, the second heat exchanger  32  is, for example, a turbine cooling air (TCA) cooler. The compressed air CA 1  flowing through the first cooling air supply line L 11  is cooled in the second heat exchanger  32  with the first medium HW circulating through the first medium circulation line L 13 . 
     The third heat exchanger  33  is provided in a second medium supply line L 14 . A supply pump  42  is provided in the second medium supply line L 14 . Here, the third heat exchanger  33  is, for example, a TCA cooler and may be a cooling tower. Therefore, the supply pump  42  is driven to cause a second medium (for example, air) A 1  to flow through the second medium supply line L 14 . Then, compressed air CA 2  flowing through the second cooling air supply line L 12  is cooled in the third heat exchanger  33  with the second medium A 1  flowing through the second medium supply line L 14 . 
     The first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  function as heat exchange amount adjusting devices that adjust the amount of heat of the compressed air CA 1  to be supplied to the second heat exchanger  32 . That is, the compressed air CA compressed by the compressor  11  is partially supplied through the first cooling air supply line L 11  and the second cooling air supply line L 12  to the turbine  13  as cooling air. In a case in which an opening degree of the first flow rate adjusting valve  34  is increased and an opening degree of the second flow rate adjusting valve  35  is decreased, a large amount of the compressed air CA flows to the first cooling air supply line L 11  side. Then, the amount of heat of the compressed air CA 1  in the first cooling air supply line L 11  increases, and the first medium HW circulating through the first medium circulation line L 13  is heated in the second heat exchanger  32 , so that the temperature is higher than before changing the opening degrees of the flow rate adjusting valves  34  and  36 . As a result, the air A in the air intake line L 1  is heated by the first heat exchanger  31  with the first medium HW that circulates through the first medium circulation line L 13  and has a high temperature, so that the temperature of the air A is higher than before changing the opening degrees. 
     On the other hand, in a case in which the opening degree of the first flow rate adjusting valve  34  is decreased and the opening degree of the second flow rate adjusting valve  35  is increased, a large amount of the compressed air CA flows to the second cooling air supply line L 12  side. Then, the amount of heat of the compressed air CA 1  in the first cooling air supply line L 11  decreases, and the first medium HW circulating through the first medium circulation line L 13  is heated by the second heat exchanger  32 , but the temperature is lower than before chancing the opening degrees of the flow rate adjusting valves  34  and  36 . As a result, although the air A in the air intake line L 1  is heated in the first heat exchanger  31  with the first medium HW that circulates through the first medium circulation line L 13  and has a low temperature, the temperature of the air A is lower than before changing the opening degrees. 
     The control device  14  controls the first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  as the heat exchange amount adjusting devices based on the temperature of the air A to be taken into the compressor  11 . A first temperature sensor  43  is provided on a downstream side of the first heat exchanger  31  in the air intake line L 1 . The first temperature sensor  43  measures the temperature of the air A that flows through the air intake line L 1  and is heated in the first heat exchanger  31 , and outputs the measured temperature to the control device  14 . The control device  14  adjusts the opening degrees of the first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  so that the temperature of the air A measured by the first temperature sensor  43  reaches a target temperature. 
     In addition, the control device  14  controls the supply pump  42  based on a temperature of the compressed air CA (CA 1 +CA 2 ) as cooling air to be supplied to the turbine  13 . A second temperature sensor  44  is provided in he joined line on a downstream side of the second heat exchanger  32  and the third heat exchanger  33  in the cooling air supply lines L 11  and L 12 . The second temperature sensor  44  measures the temperature of the compressed air CA (CA 1 +CA 2 ) that flows through the cooling air supply lines L 11  and L 12  and is supplied to the turbine  13 , and outputs the measured temperature to the control device  14 . The control device  14  adjusts a rotation speed of the supply pump  42  so that the temperature of the compressed air CA (CA 1 +CA 2 ) measured by the second temperature sensor  44  reaches a target temperature. 
     The compressed air CA (CA 1 +CA 2 ) supplied from the cooling air supply lines L 11  and L 12  to the turbine  13  is used to cool rotors and rotor blades, which are not illustrated. Therefore, it is necessary to maintain the temperature of the compressed air CA (CA 1 +CA 2 ) to be supplied to the turbine  13  at a predetermined cooling temperature required for cooling. That is, the rotation speed of the supply pump  42  is adjusted so that the temperature of the compressed air CA (CA 1 +CA 2 ) to be supplied to the turbine  13  is cooled to the predetermined cooling temperature, and the amount of heat removed from the compressed air CA 2  flowing through the second cooling air supply line L 12  is adjusted. 
     Here, the control method of the gas turbine  10  will be described.  FIG. 2  is a graph illustrating a gas turbine output with respect to an intake temperature of the gas turbine. 
     As illustrated in  FIG. 2 , the gas turbine output tends to be reduced as the intake temperature of the gas turbine is increased. Here, the intake temperature of the gas turbine is a temperature of the air to be taken into the compressor  11 , and is a temperature measured by the first temperature sensor  43 . The gas turbine output is the amount of power generated by the generator  22  coupled to the gas turbine  10 . 
     In general, in the gas turbine  10 , an operable region with respect to the gas turbine output is set, an upper limit value is a load of 100%, and a lower limit value is a load of La %. In a case in which the supplying amount of the fuel F to the combustor  12  is reduced, the gas turbine output is reduced. In a case in which the supplying amount of the fuel F is reduced, a combustion temperature decreases, and the amount of hazardous substances (for example, NOx) generated increases. The load of La % as the lower limit value is set based on the regulated amount of the hazardous substances. 
     For example, in a case in which the intake temperature of the gas turbine is 15° C. and the gas turbine output at the load of 100% is 100 MW, the load of La % is 50 MW (La 15). In this case, in a case in which the air A to be taken into the compressor  11  is heated by the first heat exchanger  31 , the intake temperature of the gas turbine increases to 20° C. Then, the gas turbine output at the load of La % is 45 MW (La 20). The gas turbine output 45 MW (La 20) at this load of La % is the same as the gas turbine output 45 MW (Lb 15) at a load of Lb % in a case in which the intake temperature of the gas turbine is 15° C. Therefore, the lower limit value in the operable region of the gas turbine  10  is reduced from the load of La % to the load Lb %, the operable region can be expanded within a range from the load of 100% (100 MW) to the load of Lb % (45 MW). 
     The gas turbine of the first embodiment includes the compressor  11  that compresses the air A, the combustor  12  that mixes and combusts the compressed air CA compressed by the compressor  11  and the fuel F, the turbine  13  that obtains rotational power using the combustion gas CG generated by the combustor  12 , the compressed air cooling heat exchanger (the third heat exchanger  33 ) that cools the compressed air CA to produce cooling air for the turbine, the air temperature adjusting heat exchangers (the first and second heat exchangers  31  and  32 ) that exchange heat between the air A and the compressed air CA, the heat exchange amount adjusting device that adjusts the heat exchange amount of each of the compressed air cooling heat exchanger and the air temperature adjusting heat exchangers, and the control device  14  that controls the heat exchange amount adjusting device, in which the control device  14  controls the heat exchange amount adjusting device based on a temperature of the air A to be taken into the compressor  11 . 
     Therefore, the air temperature adjusting heat exchanger exchanges heat between the air A and the compressed air CA, so that the air A is heated with the compressed air CA, and the air A whose temperature has increased by heating is taken into the compressor  11 . In this case, the control device  14  adjusts the heat exchange amount of the air temperature adjusting heat exchanger by the heat exchange amount adjusting device based on the temperature of the air A to be taken into the compressor  11 . That is, in a case in which the heat exchange amount of the air temperature adjusting heat exchanger is adjusted, a temperature of the air A heated with the compressed air CA is adjusted. Here, since an output of the gas turbine  10  changes depending on the temperature of the air A to be taken into the compressor  11 , the output of the gas turbine  10  can be adjusted to a target output with high accuracy regardless of a load of the gas turbine  10 , and an operation region can be expanded by the single gas turbine  10 . 
     In addition, in the first embodiment, the air A to be taken into the compressor  11  is heated with the compressed air CA that is compressed by the compressor  11  and used as cooling air for the turbine  13 . In this case, the compressed air CA that has heated the air A is cooled with the air A and transmitted to the turbine  13 , so that the compressed air CA is not discarded. Therefore, the heat of the compressed air CA that is used as the cooling air for the turbine  13  can be efficiently recovered by the air A. 
     In the gas turbine of the first embodiment, the first temperature sensor  43  that measures a temperature of the air A heat-exchanged by the air temperature adjusting heat exchanger is provided, and the control device  14  controls the heat exchange amount in the air temperature adjusting heat exchanger by the heat exchange amount adjusting device so that the temperature of the air A measured by the first temperature sensor  43  approaches a target temperature. Therefore, the temperature of the air A to be taken into the compressor  11  can be controlled with high accuracy. 
     In the gas turbine of the first embodiment, the second temperature sensor  44  that measures a temperature of the compressed air CA cooled by the third heat exchanger  33  is provided, and the control device  14  controls the heat exchange amount in the third heat exchanger  33  by the heat exchange amount adjusting device so that the temperature of the compressed air CA measured by the second temperature sensor  44  is maintained at a target temperature. Therefore, the temperature of the compressed air CA as cooling air to be supplied to the turbine  13  can be controlled with high accuracy. 
     In the gas turbine of the first embodiment, the air temperature adjusting heat exchanger includes the first heat exchanger  31  that exchanges heat between the air A and the first medium HW, and the second heat exchanger  32  that exchanges heat between the compressed air CA and the first medium HW, and the heat exchange amount adjusting device adjusts a heat exchange amount in the second heat exchanger. Therefore, the second heat exchanger  32  exchanges heat between the compressed air CA and the first medium HW to heat the first medium with the compressed air CA, the first heat exchanger  31  exchanges heat between the air A and the first medium HW to heat the air A with the first medium HW, and the air A whose temperature has increased by heating is taken into the compressor  11 . In this case, the control device  14  adjusts the amount of heat of the compressed air CA to be supplied to the second heat exchanger  32  by the heat exchange amount adjusting device based on the temperature of the air A to be taken into the compressor. That is, the amount of heat of the compressed air CA is adjusted to increase the temperature of the air A through the first medium HW and the temperature of the air A to be taken into the compressor  11  can be controlled with high accuracy. 
     In the gas turbine of the first embodiment, the first cooling air supply line L 11  and the second cooling air supply line L 12  that are used to supply the compressed air CA compressed by the compressor  11  to the turbine  13  as cooling air are provided in parallel, the second heat exchanger  32  is provided in the first cooling air supply line L 11 , the third heat exchanger  33  that exchanges heat between the compressed air CA and the second medium A 1  is provided in the second cooling air supply line L 12 , and the flow rate adjusting valves  34  and  35  are provided as the heat exchange amount adjusting devices in the first cooling air supply line L 11  and the second cooling air supply line L 12 , respectively. Therefore, opening degrees of the flow rate adjusting valves  34  and  35  are adjusted to adjust a flow rate of the compressed air CA flowing through the first cooling air supply line L 11 , so that the amount of heat supplied from the compressed air CA to the first medium HW can be adjusted by the second heat exchanger  32  provided in the first cooling air supply line L 11 , and the temperature of the air A to be taken into the compressor  11  can be adjusted by the first medium HW with high accuracy. 
     In addition, since the third heat exchanger  33  exchanges heat between the compressed air CA and the second medium A 1  such as air, and a, material that exists in the vicinity is used, it is possible to shorten a length of a pipe to be used and contribute the miniaturization of equipment and the decrease in cost. 
     The flow rate adjusting valves  34  and  35  are provided as the heat exchange amount adjusting devices in both the first cooling air supply line L 11  and the second cooling air supply line L 12 , but the flow rate adjusting valves  34  and  35  may be provided in any one of the first cooling air supply line L 11  and the second cooling air supply line L 12 . The flow rate of the compressed air CA flowing through the first cooling air supply line L 11  can be directly adjusted by the flow rate adjusting valve  34  being provided in only the first cooling air supply line L 11 . In addition, the flow rate of the compressed air CA flowing through the second cooling air supply line L 12  is adjusted by the flow rate adjusting valve  35  being provided in only the second cooling air supply line L 12 , so that the flow resistance of the compressed air CA fluctuates. Thus, the flow rate of the compressed air CA flowing through the first cooling air supply line L 11  can be indirectly adjusted. 
     In the gas turbine of the first embodiment, the second medium A 1  is air. Therefore, it is possible to shorten a length of a pipe to be used, achieve the miniaturization of equipment, and suppress the increase in cost by using air that exists in the vicinity. 
     In the gas turbine of the first embodiment, the third heat exchanger  33  is a cooling tower. Therefore, the structure can be simplified. 
     In addition, the control method of the gas turbine of the first embodiment includes a step of cooling the compressed air CA to be supplied to the turbine  13 , a step of increasing a temperature of the air A with the compressed air CA, and a step of adjusting the amount of heat of the compressed air CA, which increases a temperature of the air A based on a temperature of the air A to be taken into the compressor  11 . 
     Therefore, in a case in which the amount of heat of the compressed air CA is adjusted, a temperature of the air A heated with the compressed air is adjusted. Here, since an output of the gas turbine  10  changes depending on the temperature of the air to be taken into the compressor  11 , the output of the gas turbine  10  can be adjusted to a target output with high accuracy regardless of a load of the gas turbine  10 . 
     Second Embodiment 
       FIG. 3  is a schematic configuration diagram illustrating a combined plant of a second embodiment. Members having the same functions as those of the first embodiment described above are designated by the same reference numerals, and detailed descriptions thereof will be omitted. 
     In the second embodiment, as illustrated in  FIG. 3 , a combined cycle plant  50  includes the gas turbine  10 , a heat recovery steam generator (HRSG)  51 , a steam turbine  52 , and a generator  53 . 
     The gas turbine  10  includes the compressor  11 , the combustor  12 , the turbine  13 , and the control device  14 . Since the gas turbine  10  is substantially the same as the first embodiment described above, the descriptions thereof will be omitted. 
     The heat recovery steam generator  51  generates steam (superheated steam) ST by exhausted heat of the flue gas EG discharged from the gas turbine  10  (turbine  13 ) through the flue pas discharge line L 5 . Although not illustrated, the heat recovery steam generator  51  includes a superheater, an evaporator, and an economizer as heat exchangers. The heat recovery steam generator  51  recovers heat in the order of the superheater, the evaporator, and the economizer by passing the flue gas EG from the gas turbine  10  through the inside of the heat recovery steam generator  51  to generate the steam ST. The heat recovery steam generator  51  coupled to a stack  61  through a flue gas discharge line L 6  that discharges the used flue gas EG that has generated the steam ST. 
     The steam turbine  52  is driven by the steam ST generated by the heat recovery steam generator  51 , and includes a turbine  62 . In the turbine  62 , for example, a high-pressure turbine, a medium-pressure turbine, and a low-pressure turbine are integrally rotatably coupled with a rotating shaft. The generator  53  is coupled to the turbine  62  with a rotating shaft  63 . A steam supply line L 7  that is used to supply the steam ST in the heat recovery steam generator  51  to the turbine is provided. In the steam turbine  52 , the turbine  62  is rotated by the steam ST from the heat recovery steam generator  51 , and the generator  53  is driven by rotational power transmitted by the turbine  62  being rotated. 
     The steam turbine  52  is provided with a condenser  64  for cooling the steam ST that drives the turbine  62 . The condenser  64  cools the steam discharged from the turbine  62  with cooling water (for example, seawater) to produce condensed water. The condenser  64  transmits the generated condensed water as a water supply WS to the heat recovery steam generator  51  through a water supply line L 8 . A condensate pump  65  is provided in the water supply line L 8 . In addition, the condenser  64  is provided with a cooling water line L 9  for cooling the steam ST with cooling water. 
     The water supply line L 8  is provided with a water supply circulation line (second medium supply line)  110  that branches from between the condensate pump  65  and the heat recovery steam generator  51 . The water supply circulation line L 10  extends from the water supply line L 8 , passes through the third heat exchanger  33 , and returns to the water supply line L 8 . A flow rate adjusting valve  66  is provided in the water supply line L 8 . Therefore, an opening degree of the flow rate adjusting valve  66  is adjusted to circulate part of the water supply WS flowing in the water supply line L 8  through the water supply circulation line L 10  as a second medium. Then, the compressed air CA 2  flowing through the second cooling air supply line L 12  is cooled in the third heat exchanger  33  by the water supply WS flowing through the water supply circulation line L 10 . It is not limited that the water supply circulation line L 10  extending toward the third heat exchanger  33  is provided with the water supply line L 8  that branches at this position. For example, the water supply circulation line L 10  may be provided to branch from an internal system of the heat recovery steam generator  51 . In addition, a returning destination of the water supply circulation line L 10  is not limited to an upstream side of the heat recovery steam generator  51 , and the water supply circulation line L 10  may return to the internal system of the heat recovery steam generator  51 . 
     Therefore, during the operation of the combined cycle plant  50 , the compressor  11  compresses the air A in the gas turbine  10 , and the combustor  12  mixes and combusts the compressed air CA supplied and the fuel F. The turbine  13  is rotationally driven by the combustion gas CG supplied from the combustor  12 , and the generator  22  generates electricity. In addition, the flue gas EG discharged from the gas turbine  10  (turbine  13 ) is transmitted to the heat recovery steam generator  51 , the heat recovery steam generator  51  generates the steam ST, and the steam ST is transmitted to the steam turbine  52 . In the steam turbine  52 , the turbine  62  rotationally driven by the steam ST, and the generator  53  generates electricity. The steam ST used in the turbine  62  is cooled by the condenser  64  to be condensed water, and returns to the heat recovery steam generator  51  as the water supply WS. 
     The control device  14  controls the first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  as the heat exchange amount adjusting devices based on the temperature of the air A to be taken into the compressor  11 . That is, the control device  14  adjusts opening degrees of the first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  so that the temperature of the air A measured by the first temperature sensor  43  reaches a target temperature. 
     In addition, the control device  14  controls the opening degree of the flow rate adjusting valve  66  based on a temperature of the compressed air CA (CA 1 +CA 2 ) as cooling air to be supplied to the turbine  13 . The control device  14  adjusts the opening degree of the flow rate adjusting valve  66  so that the temperature of the compressed air CA (CA 1 +CA 2 ) measured by a second temperature sensor  44  reaches a target temperature, and the amount of heat removed from the compressed air CA 2  flowing through the second cooling air supply line L 12  is adjusted. 
     Here, a control of the gas turbine  10  in the combined cycle plant  50  will be described. 
     In a case in which it is desired to shift the gas turbine  10  in an operating state with a load of 100% (gas turbine output of 100 MW) into an operating state with a partial load (gas turbine output of 45 MW), the control device  14  reduces the amount of the fuel F to be supplied to the combustor  12 . Then, the operating state of the gas turbine  10  is lowered to an operating state (gas turbine output of 50 MW) at a load of La %. 
     The control device  14  increases the intake temperature of the gas turbine. In this case, the temperature of the air A that flows through the air intake line L 1  and is heated by the first heat exchanger  31  is input to the control device  14  from the first temperature sensor  43 , and the opening degrees of the first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  are adjusted so that the temperature measured by the first temperature sensor  43  reaches a target temperature. In a case in which the control device  14  adjusts the opening degrees of the first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  to increase the flow rate of compressed air CA 1  flowing to the first cooling air supply line L 11  side, a temperature of the first medium HW is increased, and the temperature of air A, that is, the intake temperature of the gas turbine is increased to the target temperature. As a result, the output of the gas turbine  10  is reduced to 45 MW at a load of La %. 
     In addition, the control device  14  controls the flow rate adjusting valve  66  based on a temperature of the compressed air CA (CA 1 +CA 2 ) as cooling air to be supplied to the turbine  13 . The control device  14  adjusts the opening degree of the flow rate adjusting valve  66  so that the temperature of the compressed air CA (CA 1 +CA 2 ) measured by the second temperature sensor  44  reaches a target temperature. Then, a flow rate of the water supply WS to be supplied to the third heat exchanger  33  is adjusted, and a temperature of the compressed air CA 2  cooled by the water supply WS is adjusted by the third heat exchanger  33 . As a result, the compressed air CA (CA 1 +CA 2 ) cooled to an appropriate temperature can be supplied to the turbine  13 , and the turbine  13  can be appropriately cooled. 
     As described above, in the gas turbine or the second embodiment, the second heat exchanger  32  is provided in the first cooling air supply line L 11 , the third heat exchanger  33  that exchanges heat between the compressed air CA and the water supply WS is provided in the second cooling air supply line L 12 , and the control device  14  controls the heat exchange amount adjusting devices based on a temperature of the air A to be taken into the compressor  11 . Therefore, an output of the gas turbine  10  can be adjusted to a target output with high accuracy regardless of a load of the gas turbine  10 , and an operation region can be expanded by the single gas turbine  10 . 
     In the gas turbine of the second embodiment, the second medium is used as the water supply WS that returns to the heat recovery steam generator  51 . Therefore, the increase in cost can be suppressed by using the water supply WS existing in the vicinity. 
     In addition, the combined cycle plant of the second embodiment is provided with the gas turbine  10 , the heat recovery steam generator  51  that generates the steam ST by exhausted heat of the flue gas EG discharged from the gas turbine  10 , and the steam turbine  52  that includes the turbine  62  driven by the steam ST generated by the heat recovery steam generator  51 . Therefore, regardless of the load of the gas turbine  10 , an output of the combined cycle plant  50  in which the gas turbine  10  is combined with the steam turbine  52  can be adjusted to a target output. Since a change rate of the steam turbine  52  during heating of the intake air is smaller than a change rate of the output of the gas turbine  10 , the operation region in the combined cycle plant  50  can be expanded by the output adjustment of the gas turbine  10  during the combined cycle operation. 
     Third Embodiment 
       FIG. 4  is a schematic configuration diagram illustrating a combined plant of a third embodiment. Members having the same functions as those of the second embodiment described above are designated by the same reference numerals, and detailed descriptions thereof will be omitted. 
     In the third embodiment, as illustrated in  FIG. 4 , a cooling air supply line L 15  is provided between the compressor  11  and the turbine  13 . The cooling air supply line L 15  is used to supply part of the compressed air CA compressed by the compressor  11  to the turbine  13  as cooling air. One end portion of the cooling air supply line L 15  is coupled to the combustor casing chamber (not illustrated) of the compressor  11 , and the other end portion is coupled to a space formed inside a rotor (not illustrated) of the turbine  13 . 
     The second heat exchanger  32  and the third heat exchanger  33  are provided in the cooling air supply line L 15  in series. The third heat exchanger  33  is provided on an upstream side of the cooling air supply line L 15  in a direction where the compressed air CA flows, and the second heat exchanger  32  is provided on a downstream side. 
     A first medium circulation line L 13  is provided between the first heat exchanger  31  and the second heat exchanger  32 . A circulation pump  41  and a flow rate adjusting valve  45  are provided in the first medium circulation line L 13 . The third heat exchanger  33  is provided in a water supply circulation line L 10 . 
     The control device  14  controls the first flow rate adjusting valve  45  as the heat exchange amount adjusting device based on the temperature of the air A to be taken into the compressor  11 . The control device  14  adjusts the opening degree of the flow rate adjusting valve  45  so that the temperature of the air A measured by the first temperature sensor  43  reaches a target temperature. 
     Here, a control of the gas turbine  10  in the combined cycle plant  50  will be described. 
     In a case in which it is desired to shift the gas turbine  10  in an operating state with a load of 100% (gas turbine output of 100 MW) into an operating state with a partial load (gas turbine output of 45 MW), the control device  14  reduces the amount of the fuel F to be supplied to the combustor  12 . Then, the operating state of the gas turbine  10  is lowered to an operating state (gas turbine output of 50 MW) at a load of La %. 
     The control device  14  increases the intake temperature of the gas turbine. In this case, the temperature of the air A that flows through the air intake line L 1  and is heated by the first heat exchanger  31  is input to the control device  14  from the first temperature sensor  43 , and the opening degree of the flow rate adjusting valve  45  is adjusted so that the temperature measured by the first temperature sensor  43  reaches a target temperature. In a case in which the control device  14  adjusts the opening degree of the flow rate adjusting valve  45  to increase the flow rate of the first medium HW flowing through the first medium circulation line L 13 , the heat exchange amount from the first medium HW to the air A is increased by the first heat exchanger  31  to increase the temperature, and the temperature of air A, that is, the intake temperature of the gas turbine is increased to a target temperature. As a result, the output of the gas turbine  10  is reduced to 45 MW at a load of La %. 
     In addition, the control device  14  controls the flow rate adjusting valve  66  based on the temperature of the compressed air CA as cooling air to be supplied to the turbine  13 . The control device  14  adjusts the opening degree of the flow rate adjusting valve  66  so that the temperature of the compressed air CA measured by the second temperature sensor  44  reaches a target temperature. Then, a flow rate of the water supply WS to be supplied to the third heat exchanger  33  is adjusted, and a temperature of the compressed air CA cooled by the water supply WS is adjusted by the third heat exchanger  33 . As a result, the compressed air CA at an appropriate temperature can be supplied to the turbine  13 , and the turbine  13  can be appropriately cooled. 
     As described above, in the gas turbine of the third embodiment, the cooling air supply line L 15  that is used to supply the compressed air CA compressed by the compressor  11  to the turbine  13  as cooling air is provided, the second heat exchanger  32  and the third heat exchanger  33  are provided in the cooling air supply line L 15  in series, and the flow rate adjusting valve  45  is provided as the heat exchange amount adjusting device in the first medium circulation line L 13  through which the first medium HW circulates between the first heat exchanger  31  and the second heat exchanger  32 . 
     Therefore, the opening degree of the flow rate adjusting valve  45  is adjusted to adjust a flow rate of the first medium HW flowing through the first medium circulation line L 13 , so that the amount of heat supplied from the compressed air CA to the first medium HW can be adjusted by the second heat exchanger  32  provided in the cooling air supply line L 15 , and the temperature of the air A to be taken into the compressor  11  can be adjusted by the first medium HW with high accuracy. 
     Here, in the second and third embodiments described above, the third heat exchanger  33  is, for example, a TCA cooler and may be a cooling tower. 
     Fourth Embodiment 
       FIG. 5  is a schematic configuration diagram illustrating a gas turbine of a fourth embodiment. Members having the same functions as those of the embodiments described above are designated by the same reference numerals, and detailed descriptions thereof will be omitted. 
     In the fourth embodiment, as illustrated in  FIG. 5 , the gas turbine  10  includes the first heat exchanger  31 , the third heat exchanger  33 , the first flow rate adjusting valve  34 , and the second flow rate adjusting valve  35 . In the fourth embodiment, the first heat exchanger  31  corresponds to the air temperature adjusting heat exchanger of the present invention, and directly exchanges heat between the air A to be taken into the compressor  11  and the compressed air CA generated by the compressor  11 . 
     The first heat exchanger  31  is provided in the air intake line L 1 . A first cooling air supply line L 11  and a second cooling air supply line L 12  are provided in parallel between the compressor  11  and the turbine  13 . The first heat exchanger  31  is provided in the first cooling air supply line L 11 , and the third heat exchanger  33  is provided in the second cooling air supply line L 12 . Therefore, the air A flowing through the air intake line L 1  is heated with the compressed air CA 1  flowing through the first cooling air supply line L 11  by the first heat exchanger  31 , and the compressed air CA 1  is cooled. 
     The first flow rate adjusting valve  34  is provided on an upstream side of the first heat exchanger  31  in the first cooling air supply line L 11 . A second flow rate adjusting valve  35  is provided on an upstream side of the third heat exchanger  33  in the second cooling air supply line L 12 . The first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  function as heat exchange amount adjusting devices that adjust the amount of heat of the compressed air CA 1  to be supplied to the first heat exchanger  31 . The control device  14  controls the first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  as the heat exchange amount adjusting devices based on the temperature of the air A to be taken into the compressor  11 . The first temperature sensor  43  measures the temperature of the air A that flows through the air intake line L 1  and is heated by the first heat exchanger  31 , and the control device  14  adjusts the opening degrees of the first flow rate adjusting valve  34  and the second flow rate adjusting valve  35  so that the temperature of the air A measured by the first temperature sensor  43  reaches a target temperature. 
     As described above, the gas turbine of the fourth embodiment includes the first heat exchanger  31  that directly exchanges heat between the air A and the compressed air CA, the heat exchange amount adjusting devices that adjust the amount of heat of the compressed air CA to be supplied to the first heat exchanger  31 , and the control device  14  that controls the heat exchange amount adjusting devices based on a temperature of the air A to be taken into the compressor  1 . 
     Here, since an output of the gas turbine  10  changes depending on the temperature of the air A to be taken into the compressor  11 , the output of the gas turbine  10  can be adjusted to a target output regardless of a load of the gas turbine  10 , and an operation region can be expanded by the single gas turbine  10 . In addition, since heat exchange is directly carried out between the air A to be taken into the compressor  11  and the compressed air CA generated by the compressor  11 , the system can be simplified. 
     Fifth Embodiment 
       FIG. 6  is a schematic configuration diagram illustrating a combined plant of a fifth embodiment. Members having the same functions as those of the embodiments described above are designated by the same reference numerals, and detailed descriptions thereof will be omitted. 
     In the fifth embodiment, as illustrated in  FIG. 6 , the gas turbine  10  includes the first heat exchanger  31 , the third heat exchanger  33 , and the heat exchange amount adjusting devices. In the fifth embodiment, the first heat exchanger  31  corresponds to the air temperature adjusting heat exchanger of the present invention, and directly exchanges heat between the air A to be taken into the compressor  11  and the compressed air CA generated by the compressor  11 . 
     The cooling air supply line L 15  is provided between the compressor  11  and the turbine  13 . The first heat exchanger  31  and the third heat exchanger  33  are provided in the cooling air supply line L 15  in series. That is, the first heat exchanger  31  is provided in the cooling air supply line L 15 , and the third heat exchanger  33  is provided on an upstream side. The third heat exchanger  33  is provided in the water supply circulation line L 10 , and the flow rate adjusting valve  66  is provided in the water supply circulation line L 10 . In addition, as the heat exchange amount adjusting devices, an air bypass line L 16  and a flow rate adjusting valve  71  are provided. One end portion of the air bypass line L 16  is coupled to an upstream side of the first heat exchanger  31  in the air intake line L 1 , and the other end portion is coupled to a downstream side of the first heat exchanger  31  in the air intake line L 1 . The flow rate adjusting valve  71  is provided in the air bypass line L 16 . 
     The control device  14  controls the first flow rate adjusting valves  66  and  71  as the heat exchange amount adjusting devices based on the temperature of the air A to be taken into the compressor  11 . The control device  14  adjusts the opening degrees of the flow rate adjusting valves  66  and  71  so that the temperature of the air A measured by the first temperature sensor  43  reaches a target temperature. That is, in a case in which it not necessary to adjust the temperature of the air A to be taken into the compressor  11 , the control device  14  causes the air A to be supplied from the air bypass line L 16  to the compressor  11  by the flow rate adjusting valve  71  being opened without the air A passing through the first heat exchanger  31 . 
     As described above, in the gas turbine of the fifth embodiment, the first heat exchanger  31  and the third heat exchanger  33  are provided in the cooling air supply line L 15  in series, and the flow rate adjusting valve  66  is provided as the heat exchange amount adjusting device in the water supply circulation line L 10  as the second medium supply line through which the water supply WS circulates as the second medium in the third heat exchanger  33 . 
     Therefore, the opening degree of the flow rate adjusting valve  66  is adjusted to adjust a flow rate of the water supply WS flowing through the water supply circulation line L 10 , so that the amount of heat supplied from the compressed air CA to the water supply WS can be adjusted by the third heat exchanger  33  provided in the cooling air supply line L 15 , and the temperature of the air A to be taken into the compressor  11  can be adjusted by the compressed air CA with high accuracy. 
     In the gas turbine of the fifth embodiment, as the heat exchange amount adjusting devices, the air bypass line L 16  that bypasses the first heat exchanger  31  and supplies the air A to the compressor  11 , and the flow rate adjusting valve  71  provided in the air bypass line L 16  are provided. Therefore, in a case in which it is not necessary to adjust the temperature of the air A to be taken into the compressor  11 , the air A can be supplied from the air bypass line L 16  to the compressor  11  by the flow rate adjusting valve  71  without the air passing through the first exchanger  31 . Here, in the fifth embodiment described above, the third heat exchanger  33  is, for example, a TCA cooler and may be a cooling tower. 
     Sixth Embodiment 
       FIG. 7  is a schematic configuration diagram illustrating a gas turbine of a sixth embodiment. Members having the same functions as those of each embodiment described above are designated by the same reference numerals, and detailed descriptions thereof will be omitted. 
     In the sixth embodiment, as illustrated in  FIG. 7 , the gas turbine  10  includes the first heat exchanger  31 , the second heat exchanger  32 , the third heat exchanger  33 , and the heat exchange amount adjusting device. 
     The first heat exchanger  31  is provided in the air intake line L 1 . A cooling air supply line L 17  is provided between the compressor  11  and the cooling subject member  80 . The cooling air supply line L 17  is used to supply part of the compressed air CA compressed by the compressor  11  to the cooling subject member  80  as cooling air. 
     The second heat exchanger  32  is provided in the cooling air supply line L 17 . A first medium circulation line L 13  is provided between the first heat exchanger  31  and the second heat exchanger  32 . A circulation pump  41  and a flow rate adjusting valve  45  are provided in the first medium circulation line L 13 . Therefore, the circulation pump  41  can be driven to circulate the first medium HW between the first heat exchanger  31  and the second heat exchanger  32  through the first medium circulation line L 13 . 
     The third heat exchanger  33  is provided in the first medium circulation line L 13 . The circulation pump  41  and the flow rate adjusting valve  45  are provided on one side of the first medium circulation line L 13  where the first medium HW flows from the first heat exchanger  31  to the second heat exchanger  32 , and the third heat exchanger  33  is provided on the other side of the first medium circulation line L 13  where the first medium HW flows from the second heat exchanger  32  to the first heat exchanger  31 . The third heat exchanger  33  is provided in the second medium supply line L 14 , and the supply pump  42  is provided in the second medium supply line L 14 . The second medium supply line L 14  causes the second medium (for example, air) A 1  to flow through the second medium supply line L 14 . The circulation pump  41  and the flow rate adjusting valve  45  may be provided the other side of the first medium circulation line L 13  where the first medium HW flows from the second heat exchanger  32  to the first heat exchanger  31 , and the third heat exchanger  33  may be provided on one side of the first medium circulation line L 13  where the first medium HW flows from the first heat exchanger  31  to the second heat exchanger  32 . 
     The control device  14  controls the supply pump  42  as the heat exchange amount adjusting device based on the temperature of the air A to be taken into the compressor  11 . The control device  14  adjusts a rotation speed of the supply pump  42  so that the temperature of the air A measured by the first temperature sensor  43  reaches a target temperature. In addition, a third temperature sensor  46  that measures a temperature of the compressed air CA between the second heat exchanger  32  and the cooling subject member  80  is provided in the cooling air supply line L 17 . The control device  14  controls the flow rate adjusting valve  45  based on the temperature of the compressed air CA cooled by the second heat exchanger  32 . The control device  14  adjusts the opening degree of the flow rate adjusting valve  45  so that the temperature of the compressed air CA measured by the third temperature sensor  46  reaches a target temperature. 
     As described above, in the gas turbine of the sixth embodiment, while heat exchange is carried out between part of the compressed air CA bled from the compressor  11  and the first medium HW by the second heat exchanger  32  to supply the cooled compressed air CA to the cooling subject member  80 , heat exchange is carried out between the heated first medium HW and the air A by the first heat exchanger  31 , and the control device  14  controls the supply pump  42  so that the temperature of the air A reaches a target temperature. 
     Therefore, an output of the as turbine  10  can be adjusted to a target output with high accuracy regardless of a load of the gas turbine  10 , and an operation region can be expanded by the single gas turbine  10 . 
     In the gas turbine of the present embodiment, the third heat exchanger  33  as the compressed air cooling heat exchanger is provided in the first medium circulation line L 13  that circulates the first medium HW between the first heat exchanger  31  and the second heat exchanger  32 . Therefore, the first heat exchanger  31 , the second heat exchanger  32 , and the third heat exchanger  33  can be disposed in the first medium circulation line L 13 , which enables the device to be compact. 
     Seventh Embodiment 
       FIG. 8  is a schematic configuration diagram illustrating a gas turbine of a seventh embodiment. Members having the same functions as those of the sixth embodiment described above are designated by the same reference numerals, and detailed descriptions thereof will be omitted. 
     In the seventh embodiment, as illustrated in  FIG. 8 , the gas turbine  10  includes the first heat exchanger  31 , the second heat exchanger  32 , the third heat exchanger  33 , and the heat exchange amount adjusting device. 
     The first heat exchanger  31  is provided in the air intake line L 1 . The cooling air supply line L 17  is provided between the compressor  11  and the cooling subject member  80 . The second heat exchanger  32  is provided in the cooling air supply line L 17 . A first medium circulation line L 13  is provided between the first heat exchanger  31  and the second heat exchanger  32 . The circulation pump  41 , the flow rate adjusting valve  45 , and the third heat exchanger  33  are provided in the first medium circulation line L 13 . The circulation pump  41 , the flow rate adjusting valve  45 , and the third heat exchanger  33  are provided on one side of the first medium circulation line L 13  where the first medium HW flows from the first heat exchanger  31  to the second heat exchanger  32 . The circulation pump  41 , the flow rate adjusting valve  45 , and the third heat exchanger  33  may be provided on the other side of the first medium circulation line L 13  where the first medium HW flows from the second heat exchanger  32  to the first heat exchanger  31 . 
     The control device  14  controls the first flow rate adjusting valve  45  as the heat exchange amount adjusting device based on the temperature of the air A to be taken into the compressor  11 . The control device  14  adjusts the opening degree of the flow rate adjusting valve  45  so that the temperature of the air A measured by the first temperature sensor  43  reaches a target temperature. In addition, the control device  14  controls the supply pump  42  based on the temperature of the compressed air CA cooled by the second heat exchanger  32 . The control device  14  adjusts a rotation speed of the supply pump  42  so that the temperature of the compressed air CA measured by the third temperature sensor  46  reaches a target temperature. 
     As described above, in the gas turbine of the seventh embodiment, while heat exchange is carried out between part of the compressed air CA bled from the compressor  11  and the first medium HW by the second heat exchanger  32  to supply the cooled compressed air CA to the cooling subject member  80 , heat exchange is carried out between the heated first medium HW and the air A by the first heat exchanger  31 , and the control device  14  controls the flow rate adjusting valve  45  so that the temperature of the air A reaches a target temperature. 
     Therefore, an output of the as turbine  10  can be adjusted to a target output with high accuracy regardless of a load of the gas turbine  10 , and an operation region can be expanded by the single gas turbine  10 . 
     Eighth Embodiment 
       FIG. 9  is a schematic configuration diagram illustrating a gas turbine of an eighth embodiment. Members having the same functions as those of the embodiments described above are designated by the same reference numerals, and detailed descriptions thereof will be omitted. 
     In the eighth embodiment, as illustrated in  FIG. 9 , the gas turbine  10  includes the first heat exchanger  31 , the second heat exchanger  32 , the third heat exchanger  33 , and the heat exchange amount adjusting device. 
     The first heat exchanger  31  is provided in the air intake line L 1 . The cooling air supply line L 17  is provided between the compressor  11  and the cooling subject member  80 . The second heat exchanger  32 , the first heat exchanger  31 , and the third heat exchanger  33  are provided from an upstream side of the cooling air supply line L 17  in a direction where the compressed air CA flows, in this order. In addition, in the cooling air supply line L 17 , a supply pump  91  is provided between the first heat exchanger  31  and the third heat exchanger  33 . 
     The second heat exchanger  32  is provided in a third medium supply line L 18 , and a supply pump  92  is provided in the third medium supply line L 18 . The third medium supply line L 18  causes a third medium (for example, air) A 2  to flow through the third medium supply line L 18 . The third heat exchanger  33  is provided in the second medium supply line L 14 , and the supply pump  42  is provided in the second medium supply line L 14 . 
     The control device  14  controls the supply pump  92  as the heat exchange amount adjusting device based on the temperature of the air A to be taken into the compressor  11 . The control device  14  adjusts a rotation speed of the supply pump  92  so that the temperature of the air A measured by the first temperature sensor  43  reaches a target temperature. In addition, the control device  14  controls the supply pump  42  based on the temperature of the compressed air CA cooled by the third heat exchanger  33 . The control device  14  adjusts a rotation speed of the supply pump  42  so that the temperature of the compressed air CA measured by the third temperature sensor  46  reaches a target temperature. 
     As described above, in the gas turbine of the eighth embodiment, heat exchange is carried out between part of the compressed air CA bled from the compressor  11  and the third medium A 2  by the second heat exchanger  32 , heat exchange is carried out between the compressed air CA whose temperature is adjusted and the air A by the first heat exchanger  31 , and the cooled compressed air CA is supplied to the cooling subject member  80 . On the other hand, the control device  14  controls the supply pump  92  so that the temperature of the air A reaches a target temperature. 
     Therefore, an output of the gas turbine  10  can be adjusted to a target output with high accuracy regardless of a load of the gas turbine  10 , and an operation region can be expanded by the single gas turbine  10 . 
     The configurations of the air bypass line L 16  and the flow rate adjusting valve  71  in the fifth embodiment may be used in the first to fourth embodiments and the sixth to eighth embodiments. In that case, the entire system may be used as a single gas turbine or a combined plant. 
     For example, in a case in which the configuration of the air bypass line L 16  and the flow rate adjusting valve  71  is applied to the first, second, and fourth embodiments, the control performed by the flow rate adjusting valves  34  and  35  may be stopped. In a case in which the configuration of the air bypass line L 16  and the flow rate adjusting valve  71  is applied to the third embodiment, the control performed by the flow rate adjusting valves  45  and  66  may be stopped. In addition, in a case in which the configuration of the air bypass line  116  and the flow rate adjusting valve  71  is applied to the sixth to eighth embodiments, the control performed by the flow rate adjusting valve  45 , and the supply pumps  42  and  92  may be stopped. 
     In addition, in the above-described embodiments, the temperature of the air A to be taken into the compressor  11  is measured by the first temperature sensor  43  provided in the air intake line L 11 , but the present invention is not limited to this configuration. For example, the temperature of the air to be taken into the compressor may be set to an outside air temperature, or a temperature set according to seasons, weather, time, or the like may be used. 
     In addition, in the above-described embodiments, the turbine  13  and the cooling subject member  80  are applied as members subjected to temperature adjustment, and the air for heat exchange is used as the cooling air, so that the turbine  13  and the cooling subject member  80  are cooled with the cooling air, but the present invention is not limited to this configuration. For example, a configuration in which a heating subject member is applied as a member subjected to temperature adjustment, the air for heat exchange is used as heating air, and the heating subject member is heated with the heating air may be adopted. 
     In addition, the single gas turbine or the combined plant of the present invention is applied in the above-described first to eighth embodiments, but the present invention in which the single gas turbine is applied can be applied to the combined plant. Conversely, the present invention in which the combined plant is applied can also be applied to the single gas turbine. In addition, a plurality of the heat exchange amount adjusting devices applied in individual embodiments can be applied in combination. 
     REFERENCE SIGNS LIST 
       10  Gas turbine 
       11  Compressor 
       12  Combustor 
       13  Turbine 
       14  Control device 
       21  Rotating shaft 
       22  Generator 
       31  First heat exchanger (air temperature adjusting heat exchanger) 
       32  Second heat exchanger (air temperature adjusting heat exchanger) 
       33  Third heat exchanger (compressed air cooling heat exchanger) 
       34  First flow rate adjusting valve (heat exchange amount adjusting device) 
       35  Second flow rate adjusting valve (heat exchange amount adjusting device) 
       41  Circulation pump 
       42  Supply pump 
       43  First temperature sensor 
       44  Second temperature sensor 
       45  Flow rate adjusting valve (heat exchange amount adjusting device) 
       46  Third temperature sensor 
       50  Combined cycle plant 
       51  Heat recovery steam generator 
       52  Steam turbine 
       53  Generator 
       61  Stack 
       62  Turbine 
       63  Rotating shaft 
       64  Condenser 
       65  Condensate pump 
       66  Flow rate adjusting valve (heat exchange amount adjusting device) 
       71  Flow rate adjusting valve (heat exchange amount adjusting device) 
       80  Cooling subject member 
       91  Supply pump 
       92  Supply pump 
     L 1  Air intake line 
     L 2  Compressed air supply line 
     L 3  Fuel gas supply line 
     L 4  Combustion gas supply line 
     L 5  Flue gas discharge line 
     L 6  Flue gas discharge line 
     L 7  Steam supply line 
     L 8  Water supply line 
     L 9  Cooling water line 
     L 10  Water supply circulation line (second medium supply line) 
     L 11  First cooling air supply line 
     L 12  Second cooling air supply line 
     L 13  First medium circulation line 
     L 14  Second medium supply line 
     L 15  Cooling air supply line 
     L 16  Bypass line 
     L 17  Cooling air supply line 
     L 18  Third medium supply line 
     A Air 
     A 1  Second medium 
     A 2  Third medium 
     CA, CA 1 , CA 2  Compressed air 
     CC Combustion gas 
     EG Flue gas 
     F Fuel 
     HW First medium 
     ST Steam 
     WS Water supply