Apparatus for controlling turbine blade tip clearance and gas turbine including the same

A gas turbine comprising:

• a compressor configured to compress outside air;
• a combustor configured to mix fuel with the air compressed by the compressor to burn a mixture thereof;
• a turbine comprising a plurality of turbine blades in a turbine casing rotated by combustion gas discharged from the combustor to generate power;
• and
• an apparatus for controlling tip clearance between the turbine casing and the turbine blade, wherein the apparatus for controlling tip clearance comprises:
• a casing surrounding the turbine blade;
• a cooling plate installed in a groove of the turbine casing and formed in a circumferential direction in the casing, the cooling plate being contacted by cold air supplied thereto;
• an upper plate mounted in the groove of the turbine casing radially outside the cooling plate and having a plurality of cold air holes formed therein;
• a cylinder integrally extending radially inwardly from an inner peripheral surface of the upper plate and having a plurality of cooling holes formed on a side thereof;
• and
• a ring segment mounted radially inside the cooling plate.