Mitsubishi Hitachi Power Systems, Ltd.

Mitsubishi Power, Ltd.

Takuya Takeda

Ryo Kawai

Chihiro Myoren

Hidefumi Araki

Shinichi Higuchi

Yasuo Takahashi

Kenji Nanataki

Ryou Akiyama

Ichiro Miyoshi

Yasunori Kimura

Yasushi Iwai

Tetsuya Nakamura

The invention aims to shorten the time required for start-up and prevent excessive increases in the heat loads on turbine blades. A humid air turbine includes a compressor; a combustor; a turbine; an exhaust heat recovery unit for recovering the heat of turbine exhaust gas to generate high-temperature moisture; a fuel supply system having a fuel flow rate control valve; an exhaust temperature acquiring unit for acquiring a temperature of the exhaust discharged while the turbine is driven; a combustion gas moisture ratio calculating section for calculating a ratio of moisture contained in combustion gas; an exhaust temperature upper limit calculating section for setting an exhaust temperature upper limit based on the combustion gas moisture ratio and the pressure ratio; an exhaust temperature difference calculating section for calculating the difference between the exhaust temperature upper limit and the exhaust temperature; a fuel flow rate command value calculating section for calculating a fuel flow rate command value using the exhaust temperature difference; and a control command value output section for outputting a command signal to the fuel flow rate control valve based on the command value selected by a fuel flow rate command value selecting section.

Humid air turbine

A two-shaft gas turbine control system and method are provided that can enhance the efficiency and reliability thereof by controlling the amount of intake air spray and the rotational speed of a high-pressure turbine in accordance with the aperture of an inlet guide vane in a state where a two-shaft gas turbine is being operated with the efficiency of its compressor reduced. The control system includes a droplet spray device for spraying droplets to intake air for the compressor and a controller. The controller includes a fuel control section for adjusting a flow rate of the fuel to be supplied to the combustor, a spray flow rate control section for adjusting a flow rate of spray water to be supplied to the droplet spray device, an inlet guide vane aperture control section for adjusting the aperture of the inlet guide vane, and an efficiency improvement control section for outputting a command signal for bringing a balance between driving force for the compressor and power output of the high-pressure turbine to the fuel control section, the spray flow rate control section and the inlet guide aperture control section. In response to the commands from the improvement control section, the controller reduces the rotational speed of the high-pressure turbine and controls the inlet guide vane so as to be more open, thereby appropriately controlling the flow rate of the spray water.

System and method of controlling a two-shaft gas turbine

A turbine blade includes cooling passages formed inside the blade and extending in a blade height direction, blade surfaces on a suction side and a pressure side being covered with thermal barrier coating, a design point on a suction side being set on the blade surface on the suction side of each blade section perpendicular to the blade height direction within a range from a position on a back side of and including a throat position, and to a position in front of and not including a tailing end of a final cooling passage. Thickness distribution of the thermal barrier coating on the suction side of each blade section is configured such that a thickness of the thermal barrier coating is uniform from a blade leading edge to the design point and gradually reduces from the design point toward the back side up to the blade trailing edge.

Turbine blade

An exhaust frame includes: an inner casing; an inner diffuser which defines, between the inner diffuser and the inner casing, an annular inner cooling passage connected to a final-stage wheel space; an outer diffuser which defines an exhaust passage between the outer diffuser and the inner diffuser; an outer casing which defines an annular outer cooling passage between the outer casing and the outer diffuser; a strut which connects the inner casing and the outer casing to each other while crossing the exhaust passage; a strut cover which connects the inner diffuser and the outer diffuser to each other, and defines, between the strut cover and the strut, an annular connection passage connecting the inner cooling passage and the outer cooling passage to each other; and a communication hole provided in a wall of the outer cooling passage at a position on the downstream side of a center line of the strut in the flow direction of a combustion gas.

Exhaust frame

Growing community of inventors

Yokohama, Japan

Takuya Takeda