Stator Blade Heating System, Steam Turbine Having Stator Blade Heating System, Stator Blade Segment, and Stator Blade Heating Method
A stator blade heating system is to heat a hollow stator blade of a steam turbine, and includes: an electromagnetic coil disposed within a hollow portion of the stator blade; and a heating device electrically connected to the electromagnetic coil and capable of supplying an alternating current to the electromagnetic coil. A core wound with the electromagnetic coil is disposed within the hollow portion of the stator blade. The stator blade heating system further includes a regulator that regulates output of the alternating current of the heating device, and a temperature sensor that detects temperature of the stator blade. The regulator regulates the output of the heating device on the basis of the temperature detected by the temperature sensor.
1 . A stator blade heating system for heating a hollow stator blade of a steam turbine, the stator blade heating system comprising:
an electromagnetic coil disposed within a hollow portion of the stator blade; and
a heating device electrically connected to the electromagnetic coil and capable of supplying an alternating current to the electromagnetic coil.
2 . The stator blade heating system according to claim 1 , further comprising:
a core disposed within the hollow portion of the stator blade and wound with the electromagnetic coil.
3 . The stator blade heating system according to claim 2 , wherein the core is disposed at a position of an outer end portion in a radial direction of the steam turbine in the stator blade.
4 . The stator blade heating system according to claim 1 , further comprising:
a regulator that regulates output of the alternating current of the heating device; and
a temperature sensor that detects a temperature of the stator blade, wherein
the regulator is configured to regulate the output of the heating device on a basis of the temperature detected by the temperature sensor.
5 . The stator blade heating system according to claim 4 , wherein
the regulator is configured to perform feedback control of the output of the heating device such that the temperature detected by the temperature sensor is within a predetermined range.
6 . The stator blade heating system according to claim 4 , wherein
the regulator is configured to stop the output of the heating device when the temperature detected by the temperature sensor exceeds a threshold value set in advance.
7 . The stator blade heating system according to claim 4 , wherein
the temperature sensor is a thermocouple, the thermocouple being attached on an inner surface of the stator blade.
8 . A steam turbine comprising the stator blade heating system according to claim 1 .
9 . A stator blade segment being one of a plurality of structures into which an annular nozzle diaphragm is divided in the circumferential direction, the annular nozzle diaphragm being formed by coupling a plurality of hollow stator blades arranged in a circumferential direction, the stator blade segment comprising:
an electromagnetic coil disposed within a hollow portion of the stator blade, the electromagnetic coil being electrically connectable to a heating device configured to output an alternating current.
10 . The stator blade segment according to claim 9 , wherein
a core wound with the electromagnetic coil is disposed within the hollow portion of the stator blade.
11 . The stator blade segment according to claim 10 , wherein
the core is disposed at a position of an outer circumferential side end portion in the stator blade.
12 . A stator blade heating method of heating a hollow stator blade of a steam turbine, the stator blade heating method comprising:
supplying an alternating current to an electromagnetic coil disposed within a hollow portion of the stator blade;
detecting a temperature of the stator blade; and
regulating output of the alternating current to the electromagnetic coil on a basis of the detected temperature.
13 . The stator blade heating method according to claim 12 , wherein
the output of the alternating current to the electromagnetic coil is regulated such that the detected temperature is within a predetermined range.
14 . The stator blade heating method according to claim 12 , wherein
the supply of the alternating current to the electromagnetic coil is stopped when the detected temperature exceeds a threshold value set in advance.