Abstract: A control device selects and executes any of normal control of outputting a fuel flow rate command value through feedback control based on a deviation between a target output and an actual output of a gas turbine and load decreasing control of outputting the fuel flow rate command value for reducing an output of the gas turbine to a predetermined target output during a predetermined first time without performing feedback control, and performs control of reducing a flow rate of air flowing into a compressor of the gas turbine such that an air-fuel ratio settles within a predetermined range, in parallel with execution of the load decreasing control when the load decreasing control is selected.

Abstract: An IGV opening command value is corrected to calculate an actual opening equivalent value that indicates an approximate value of an actual opening. A temperature estimation value, for a case where a mixture of fuel and in-flowing air is combusted, is calculated using the actual opening equivalent value, atmospheric conditions, and an output from a gas turbine. A fuel distribution command value that indicates distribution of fuel output from a plurality of fuel supply systems is calculated on the basis of the temperature estimation value. The fuel distribution command value and a fuel control signal command value that indicates the total flow rate of fuel to be output to the plurality of fuel supply systems are acquired, and respective valve openings of fuel flow rate regulating valves of the fuel supply systems are calculated on the basis of the fuel distribution command value and the fuel control signal command value.

Abstract: An IGV opening command value is corrected to calculate an actual opening equivalent value that indicates an approximate value of an actual opening. A temperature estimation value, for a case where a mixture of fuel and in-flowing air is combusted, is calculated using the actual opening equivalent value, atmospheric conditions, and an output from a gas turbine. A fuel distribution command value that indicates distribution of fuel output from a plurality of fuel supply systems is calculated on the basis of the temperature estimation value. The fuel distribution command value and a fuel control signal command value that indicates the total flow rate of fuel to be output to the plurality of fuel supply systems are acquired, and respective valve openings of fuel flow rate regulating valves of the fuel supply systems are calculated on the basis of the fuel distribution command value and the fuel control signal command value.

Abstract: A combustor includes: a pilot burner; a plurality of main burners, each of which is provided radially and outwardly along a circumferential direction about the pilot burner, and including a main nozzle disposed in a main burner cylinder; and an extension tube provided to extend toward a downstream side from the main burner cylinder of each of the main burners. The extension tube has a circular inlet communicating with the main burner cylinder, and an outlet at the downstream side comprising two radial edges parallel to the radial direction and two circumferential edges formed along the circumferential direction so as to connect both ends of the radial edges. The combustor further includes an air passage formed outside of the main burner cylinder; and an inner communication hole (formed at the side of the inlet of the extension tube and at a position corresponding to the radially and inwardly circumferential edge for allowing communication between the air passage and the inside of the extension tube.

Abstract: A combustor according to the invention includes a combustor basket to which air A is supplied from the outside, a plurality of first nozzles that are annularly provided along the inner periphery of the combustor basket and that supply premixed gas M of the air and fuel to the inside of the combustor basket, and a transition piece in which the combustor basket is connected to a base end thereof and which burns the premixed gas supplied from the first nozzles, thereby forming a flame front spread to the outer periphery side toward the leading end in an axial direction, wherein each first nozzle supplies the premixed gas with fuel concentration changed around the center axis of the first nozzle such that the flame front has a uniform temperature in the axial direction.

Abstract: A combustor includes a combustor external cylinder, a tubular combustor basket installed in the combustor external cylinder, a compressed air channel defined between the combustor external cylinder and the combustor basket, and a plurality of fuel nozzles installed in the combustor basket. Compressed air flowing along the compressed air channel is approximately reversed in the flow direction at an end of the combustor basket, and is introduced into the plurality of fuel nozzles. Fuel injection pegs made up of an upstream side fuel injection peg injecting upstream side fuel and a downstream side fuel injection peg injecting downstream side fuel, are installed in the compressed air channel. Concentration fluctuation of the upstream side fuel caused by pressure fluctuation in the combustor is configured so as to reduce a peak of concentration fluctuation of the downstream side fuel at a combustion start position of the combustor.

Abstract: A combustor includes a combustion chamber and an acoustic liner, wherein through-holes through are formed in a wall of the combustion chamber, a plurality of rows of the through-holes is arranged in a lengthwise direction of the combustor, the through-holes of a first through-hole row are shifted with respect to the through-holes of a second through-hole row so that centers of the through-holes of the first and second through-hole rows adjacent each other are staggered in the circumferential direction, cooling grooves are formed so as to avoid the through-holes inside that is sandwiched between the outer peripheral surface and the inner peripheral surface of the combustion chamber, and the cooling grooves include transverse cooling grooves extending in the circumferential direction between rows of the through-holes, and longitudinal cooling grooves extending in the lengthwise direction between the through-holes and connecting the transverse cooling grooves adjacent to each other.

Abstract: A combustor of the present invention includes: a pilot burner; a plurality of main burners (36), each of which is provided radially and outwardly along a circumferential direction about the pilot burner, and including a main nozzle (36a) disposed in a main burner cylinder (36A); an extension tube (36B) provided to extend toward a downstream side from the main burner cylinder of each of the main burners, the extension tube having a circular inlet (36Ba) communicating with the main burner cylinder, and an outlet (36Bb) at the downstream side comprising two radial edges (36Bc) parallel to the radial direction and two circumferential edges (36Bd) formed along the circumferential direction so as to connect both ends of the radial edges; an air passage (36E) formed outside of the main burner cylinder; and an inner communication hole (H1).

Abstract: The combustor of the present invention is provided with a combustor basket to which air A is supplied from outside, first nozzles which are installed in a plural number annularly along an inner circumference of the combustor basket to individually supply premixed gas M of the air (A) with a fuel (f) into the combustor basket, and a transition piece, a base end of which is connected to the combustor basket, and which burns the premixed gas (M) supplied from the first nozzles to form a flame front (F) which spreads to an outer circumference toward the leading end in an axial direction. Each of the first nozzles supplies the premixed gas (M) by changing the fuel concentration around the center axis of the first nozzle so that the flame front (F) is made uniform in temperature in the axial direction.