Abstract: A twin-shaft gas turbine can be used for 50 and 60 Hz power generation without using a reducer. A gas generator includes a compressor that generates compressed air, a burner that burns a fuel mixed with the compressed air received from the compressor so as to generate combustion gas, and a high-pressure turbine that is rotationally driven by the combustion gas received from the burner and generates driving force for the compressor. An output turbine includes a low-pressure turbine that is driven by exhaust gas received from the high-pressure turbine and a power generator that is driven by the low-pressure turbine. A control device reduces opening degree of IGV of the compressor and thereby reduces power of the compressor, and the rotational frequency of the gas generator is increased in a full-speed no-load operating state of the power generator.

Abstract: It is an object of the present invention to provide a compressor that has a simple structure, produces a damping effect and improves aerodynamic performance. In a compressor including stator blades 4 circumferentially mounted to an inner circumferential surface side of a casing 6 forming a annular path; and an inner barrel 7 supported by the casing and arranged on the radially inside of the stator blade as a partition wall on the radial side of the annular path; the stator blade includes an outer shroud 10 mounted to an inner circumferential surface of the casing at a position facing the inner barrel, and an inner shroud 11 supporting a blade portion at an inner diameter side, the inner shroud being disposed in an annular groove formed in an outer circumferential surface of the inner barrel facing the inner shroud. The stator blade including the outer shroud 10, the inner shroud 11 and the blade portions 9 are formed in a monolithic structure by milling.

Abstract: A two-shaft gas turbine is capable of starting premixed combustion without extinguishing a flame. The two-shaft gas turbine includes a combustor and a gas generator controller. The combustor has a premix burner that includes combustion regions in which premixed combustion is to be carried out individually. The gas generator controller controls the combustor. In a method for starting the premixed combustion in the combustor, the gas generator controller selects at least one of the combustion regions in which the premixed combustion is to be carried out, on the basis of a fuel-air ratio, and starts premix combustion in the selected combustion region or separately in each of the selected combustion regions. Further, as the fuel-air ratio is increased, the controller increases the number of the selected region in which the premixed combustion is carried out.

Abstract: A gas turbine is provided that can suppress an increase in the supplied amount of cooling air in clearance adjustment through casing cooling. The gas turbine 101 includes a turbine casing 19 enclosing a turbine shaft 105, the turbine casing 19 including a cooling air header 21 and a cooling passage 24; and an exhaust diffuser 113 connected to the exhaust side of the casing 19, the exhaust diffuser 113 including an exhaust diffuser cooling passage 26. A plate 22 formed with a plurality of impingement cooling holes 28 is installed inside the cooling air header, and a route is formed which allows cooling air introduced from the impingement cooling holes to flow from the casing cooling passage to the diffuser cooling passage.

Abstract: An airfoil profile is formed such that a passage width ratio, represented in a dimensionless manner, of an inter-blade passage width of vane root cross-section to an outlet throat width substantially monotonously decreases from a blade inlet toward a blade outlet. The blade has a blade airfoil profile shape in an envelope within a range of ±2.0 mm in a direction normal to any surface location of an airfoil profile portion. The airfoil profile portion has a reference airfoil contour represented in Cartesian coordinates, wherein Z is a distance representing a sectional height from a root of the airfoil profile portion. The contours represented by X and Y at each section Z are joined smoothly with one another in a blade height direction to form a complete shape of the airfoil profile portion.

Abstract: A twin-shaft gas turbine, which has a gas generator including a compressor, a combustor, and a high-pressure turbine, is configured to make a first control mode and a second control mode selectively useable for control of the gas generator. In addition, in the first control mode, an IGV angle in the compressor is controlled in accordance with a corrected shaft rotation speed of the gas generator, and in the second control mode, the IGV angle is controlled to maintain a constant gas generator shaft rotation speed. Furthermore, the first control mode is used to start, to stop, and to operate the turbine under fixed or lower load conditions, and that the second control mode is used under operational states other than those to which the first control mode is applied.

Abstract: An airfoil profile is formed such that a passage width ratio, represented in a dimensionless manner, of an inter-blade passage width of vane root cross-section to an outlet throat width substantially monotonously decreases from a blade inlet toward a blade outlet. The blade has a blade airfoil profile shape in an envelope within a range of .+?.2.0 mm in a direction normal to any surface location of an airfoil profile portion. The airfoil profile portion has a reference airfoil contour represented in Cartesian coordinates wherein Z is a distance representing a sectional height from a root of the airfoil profile portion. The contours represented by X and Y at each section Z are joined smoothly with one another in a blade height direction to form a complete shape of the airfoil profile portion.

Abstract: A twin-shaft gas turbine 1, which has a gas generator 2 including a compressor 7, a combustor 8, and a high-pressure turbine 9, is configured to make a first control mode and a second control mode selectively useable for control of the gas generator. In addition, in the first control mode, an IGV angle in the compressor is controlled in accordance with a corrected shaft rotation speed of the gas generator, and in the second control mode, the IGV angle is controlled to maintain a constant gas generator shaft rotation speed. Furthermore, the first control mode is used to start, to stop, and to operate the turbine under fixed or lower load conditions, and that the second control mode is used under operational states other than those to which the first control mode is applied.

Abstract: A combustor includes two upstream parts of fuel supply system supplying gaseous fuels of two types having different heating values from each other, a three-way fuel transfer valve merging the two upstream parts of fuel supply system with each other, a plurality of gaseous fuel supply subsystems supplying a combustion chamber with the gaseous fuels supplied through the three-way fuel transfer valve and branched, and a plurality of burners injecting, corresponding to each of the gaseous fuel supply subsystems, the gaseous fuel supplied from the gaseous fuel supply subsystem into the combustion chamber.

Abstract: A twin-shaft gas turbine 1, which has a gas generator 2 including a compressor 7, a combustor 8, and a high-pressure turbine 9, is configured to make a first control mode and a second control mode selectively usable for control of the gas generator. In addition, in the first control mode, an IGV angle in the compressor is controlled in accordance with a corrected shaft rotation speed of the gas generator, and in the second control mode, the IGV angle is controlled to maintain a constant gas generator shaft rotation speed. Furthermore, the first control mode is used to start, to stop, and to operate the turbine under fixed or lower load conditions, and that the second control mode is used under operational states other than those to which the first control mode is applied.

Abstract: The temperature rise of a wheel space between a high-pressure turbine and a low-pressure turbine is suppressed. Cooling air is led from outside a casing 17 to a wheel space via a low-pressure turbine initial stage stator blade 5 and a diaphragm 11. An upstream side space seal portion 41 is adapted to restrict and divide the upstream side space into an outer circumferential portion 25 and an inner circumferential portion 27 and to allow cooling air to the upstream side space outer circumferential portion 27 to blow out into the upstream side space outer circumferential portion 25. Also, a downstream side space seal portion 42 is adapted to restrict and divide the downstream side space into an outer circumferential portion 26 and an inner circumferential portion 28 and to allow cooling air to blow out into the downstream side space outer circumferential portion 26.

Abstract: It is an object of the present invention to provide a compressor that has a simple structure, produces a damping effect and improves aerodynamic performance. In a compressor including stator blades 4 circumferentially mounted to an inner circumferential surface side of a casing 6 forming a annular path; and an inner barrel 7 supported by the casing and arranged on the radially inside of the stator blade as a partition wall on the radial side of the annular path; the stator blade includes an outer shroud 10 mounted to an inner circumferential surface of the casing at a position facing the inner barrel, and an inner shroud 11 supporting a blade portion at an inner diameter side, the inner shroud being disposed in an annular groove formed in an outer circumferential surface of the inner barrel facing the inner shroud. The stator blade including the outer shroud 10, the inner shroud 11 and the blade portions 9 are formed in a monolithic structure by milling.

Abstract: A two-shaft gas turbine is capable of starting premixed combustion without extinguishing a flame. The two-shaft gas turbine includes a combustor and a gas generator controller. The combustor has a premix burner that includes combustion regions in which premixed combustion is to be carried out individually. The gas generator controller controls the combustor. In a method for starting the premixed combustion in the combustor, the gas generator controller selects at least one of the combustion regions in which the premixed combustion is to be carried out, on the basis of a fuel-air ratio, and starts premix combustion in the selected combustion region or separately in each of the selected combustion regions. Further, as the fuel-air ratio is increased, the controller increases the number of the selected region in which the premixed combustion is carried out.

Abstract: A twin-shaft gas turbine 1, which has a gas generator 2 including a compressor 7, a combustor 8, and a high-pressure turbine 9, is configured to make a first control mode and a second control mode selectively useable for control of the gas generator. In addition, in the first control mode, an IGV angle in the compressor is controlled in accordance with a corrected shaft rotation speed of the gas generator, and in the second control mode, the IGV angle is controlled to maintain a constant gas generator shaft rotation speed. Furthermore, the first control mode is used to start, to stop, and to operate the turbine under fixed or lower load conditions, and that the second control mode is used under operational states other than those to which the first control mode is applied.

Abstract: A two-shaft gas turbine is capable of starting premixed combustion without extinguishing a flame. The two-shaft gas turbine includes a combustor and a gas generator controller. The combustor has a premix burner that includes combustion regions in which premixed combustion is to be carried out individually. The gas generator controller controls the combustor. In a method for starting the premixed combustion in the combustor, the gas generator controller selects at least one of the combustion regions in which the premixed combustion is to be carried out, on the basis of a fuel-air ratio, and starts premix combustion in the selected combustion region or separately in each of the selected combustion regions. Further, as the fuel-air ratio is increased, the controller increases the number of the selected region in which the premixed combustion is carried out.

Abstract: A twin-shaft gas turbine 1, which has a gas generator 2 including a compressor 7, a combustor 8, and a high-pressure turbine 9, is configured to make a first control mode and a second control mode selectively usable for control of the gas generator. In addition, in the first control mode, an IGV angle in the compressor is controlled in accordance with a corrected shaft rotation speed of the gas generator, and in the second control mode, the IGV angle is controlled to maintain a constant gas generator shaft rotation speed. Furthermore, the first control mode is used to start, to stop, and to operate the turbine under fixed or lower load conditions, and that the second control mode is used under operational states other than those to which the first control mode is applied.

Abstract: The temperature rise of a wheel space between a high-pressure turbine and a low-pressure turbine is suppressed. Cooling air is led from outside a casing 17 to a wheel space via a low-pressure turbine initial stage stator blade 5 and a diaphragm 11. An upstream side space seal portion 41 is adapted to restrict and divide the upstream side space into an outer circumferential portion 25 and an inner circumferential portion 27 and to allow cooling air to the upstream side space outer circumferential portion 27 to blow out into the upstream side space outer circumferential portion 25. Also, a downstream side space seal portion 42 is adapted to restrict and divide the downstream side space into an outer circumferential portion 26 and an inner circumferential portion 28 and to allow cooling air to blow out into the downstream side space outer circumferential portion 26.

Abstract: A combustor includes two upstream parts of fuel supply system supplying gaseous fuels of two types having different heating values from each other, a three-way fuel transfer valve merging the two upstream parts of fuel supply system with each other, a plurality of gaseous fuel supply subsystems supplying a combustion chamber with the gaseous fuels supplied through the three-way fuel transfer valve and branched, and a plurality of burners injecting, corresponding to each of the gaseous fuel supply subsystems, the gaseous fuel supplied from the gaseous fuel supply subsystem into the combustion chamber.

Abstract: An airfoil profile is formed such that a passage width ratio, represented in a dimensionless manner, of an inter-blade passage width of vain root cross-section to an outlet throat width substantially monotonously decreases from a blade inlet toward a blade outlet. The blade has a blade airfoil profile shape in an envelope within a range of ±2.0 mm in a direction normal to any surface location of an airfoil profile portion. The airfoil profile portion has a reference airfoil contour represented in Cartesian coordinates wherein Z is a distance representing a sectional height from a root of the airfoil profile portion. The contours represented by X and Y at each section Z are joined smoothly with one another in a blade height direction to form a complete shape of the airfoil profile portion.

Abstract: To provide a plant facility which requires no transmission such as reduction gear and speed up gear, thus increasing the plant efficiency. The plant facility has a turbine which rotates at a frequency higher than the electrical power supply frequency, a generator which is directly connected to the turbine and rotates at the same rotating speed with that of the turbine, and an electrical motor which is directly connected to a load apparatus and driven by electricity at a frequency higher than the electrical power supply frequency generated from the generator. The load apparatus is driven at the same rotating speed with that of the electrical motor.