A first steam turbine and a second steam turbine of a combined cycle plant are connected by a reheat steam line via a reheat section of an exhaust heat recovery boiler. The reheat steam line and a condenser are connected by a second bypass line. A control device includes: a determination unit that determines whether or not the flow rate of first steam flowing into the first steam turbine has reached a stipulated flow rate; a command output unit that, upon determining that the flow rate of the first steam flowing into the first steam turbine has reached the stipulated flow rate, outputs a close command to close a ventilator valve that is provided in the second bypass line and is open; and a threshold alteration unit that alters the threshold with which the determination unit determines whether or not the stipulated flow rate has been reached, the threshold being positively correlated with a temperature of the first steam.

A dual trip manifold assembly (TMA) includes an isolation valve assembly having a first valve configured to receive a flow of fluid from a hydraulic system fluid supply. The first valve is configured to channel the flow of fluid to at least one hydraulic circuit. The isolation valve assembly also includes a second valve configured to receive the flow of fluid from the at least one hydraulic circuit of the at least two hydraulic circuits. The second valve is further configured to channel the fluid flow to a trip header and to receive the fluid flow from the trip header. The first valve and the second valve are synchronized to each other such that rotation of one of said first and second valves causes a substantially similar rotation in the other of said first and second valves header.

A closed loop thermal cycle expander bypass flow control is described. An expander is positioned within and surrounded by a housing to receive a working fluid and rotate in response to expansion of the working fluid flowing through the expander. A bypass channel is positioned within and surrounded by the housing to define a fluid flow path that bypasses the expander. A fluid flow control sub-assembly is fluidically coupled to the expander and the bypass channel, and attached to the housing. The fluid flow control sub-assembly can receive the working fluid at a housing inlet and either flow the working fluid through the expander and block the working fluid from flowing through the bypass channel, or flow the working fluid through the housing bypassing the expander, flow the working fluid out via a housing outlet, and block the working fluid from flowing through the expander.

In one embodiment, an exhaust chamber cooling apparatus measures output of a generator driven by a steam turbine, a temperature in an exhaust chamber of the turbine, and a pressure in a condenser that changes steam from the turbine back to water. The apparatus further outputs a first signal when it is detected that a measurement value of the output is larger than a first setting value and a measurement value of the temperature is larger than a second setting value, and a second signal when it is detected that the measurement value of the output is smaller than the first setting value and a measurement value of the pressure or a calculation value obtained from the measurement value of the pressure is larger than a third setting value. The apparatus further controls supply of a cooling fluid into the chamber, based on the first or second signal.

A solar thermal power generation system includes a solar heat collection system that generates superheated steam by solar heat, a main power generation system that performs power generation by part of the superheated steam generated by the solar heat collection system, a solar heat storage/release system that stores heat in a heat storage medium or releases the heat stored in the heat storage medium, and a secondary power generation system that performs power generation by saturated steam generated by the heat storage or the heat release in the solar heat storage/release system. The solar heat storage/release system includes a heat storage heater for exchanging heat between the rest of the superheated steam generated by the solar heat collection system and the heat storage medium to store heat in the heat storage medium and to generate saturated steam, a low-temperature tank for containing the heat storage medium to be supplied to the heat storage heater, and a high-temperature tank for containing the heat storage medium after the heat storage in the heat storage heater. The secondary power generation system includes a saturated steam turbine into which the saturated steam generated by the heat storage heater can be introduced.

A system for the generation of electrical power using a solar collector that heats water using solar energy. The heated water is stored in a first tank. A vessel is connected to the first tank through a pipe and includes a headspace within which the heated water is sprayed to thereby generate steam. The headspace pressure is lower than atmospheric pressure and the water not converted to steam is collected in a pool at the bottom of the vessel to be fed back into the first tank. The steam is fed to a partial admission turbine that drives an electrical generator.

The present invention provides a generalized frequency conversion system for a steam turbine generator unit. The system comprises at least a steam turbine (T) with an adjustable rotating speed, a water feeding pump (BFP), a generator (G), a speed increasing gearbox (GB), a variable frequency bus (a, c) and an auxiliary machine connected thereto. With a change in load of the unit, parameters of steam entering the steam turbine (T) and an extracted steam amount are correspondingly adjusted (changed), so that the rotating speed of the steam turbine (T) changes correspondingly; and thus the rotating speed of the water feeding pump (BFP) is changed through the speed increasing gearbox (GB) on the one hand, and the frequency of an alternating current outputted by the generator (G) is changed on the other hand. Other types of frequency converters do not need to be additionally provided. The system is simple, reliable, low in cost, and high in efficiency.

In an operation method of a multi-shaft combined cycle plant, a low-load mode in which an output of the multi-shaft combined cycle plant is adjusted by adjustment of only an output of a gas turbine and a high-load mode in which the output of the multi-shaft combined cycle plant is adjustable by adjustment of the output of the gas turbine and adjustment of an output of a steam turbine are switched according to a demanded load. In the low-load mode, steam at a standby flow rate at which the steam turbine is capable of maintaining a predetermined initial load is supplied to the steam turbine, and the initial load is applied to the steam turbine.

In one embodiment, a plant control apparatus controls a power plant that includes a combustor to burn fuel with oxygen introduced from an inlet guide vane to generate gas, a gas turbine driven by the gas from the combustor, a heat recovery steam generator to generate steam using heat of an exhaust gas from the gas turbine, and a steam turbine driven by the steam from the heat recovery steam generator. The apparatus controls an angle of the inlet guide vane before a start of the steam turbine to a first angle, controls the angle of the inlet guide vane after the start of the steam turbine to a second angle larger than the first angle, and reduce the angle of the inlet guide vane from the second angle to the first angle or more during the predetermined period.

A system includes an HRSG that includes a plurality of heat exchanger sections fluidly coupled to each other. The plurality of heat exchanger sections comprises at least one economizer, at least one evaporator, at least one reheater, and at least one superheater. In addition, the HRSG includes an additional heat exchanger section coupled to two different heat exchanger sections of the plurality of heat exchanger sections. Further, the HRSG includes a controller programmed to selectively fluidly couple the additional heat exchanger section to one of the two different heat exchanger sections to alter a heat duty for the selected heat exchanger section fluidly coupled to the additional heat exchanger.