Abstract: Disclosed is an approach that uses an overload valve to operate a steam turbine reheat section. In one embodiment, the steam turbine reheat section receives a supply of reheated steam from a reheater at a first steam admission location via a reheat valve. The steam turbine reheat section is further adapted to receive a diverted portion of the reheated steam from the reheater at a second steam admission location via the overload valve.

Abstract: A method of integrating a supplemental steam source into a combined cycle plant comprising a gas turbine engine, generator and heat recovery steam generator (HRSG) by providing a solar steam generation subsystem that captures and transfers heat using solar radiation to produce supplemental superheated steam; providing a steam turbine operatively connected to the gas turbine; and injecting a portion of the steam formed by solar radiation into one or more intermediate stages of the high pressure section of the steam turbine. The exemplary method uses steam produced by the HRSG (having one, two or three pressure levels and with or without reheat), as well as steam produced by a solar steam generation subsystem when the plant is operating at full capacity. Significantly, the throttle pressure of the high pressure steam turbine remains substantially the same when the solar steam generation is either active or inactive.

Abstract: Systems and methods for actively controlling the temperature in at least portions of a steam path associated with a steam turbine are disclosed. An active temperature control unit is configured to activate one or more attemperators to maintain temperatures in at least a portion of the steam path below a pre-determined threshold. By maintaining the temperature, those portions of the steam path may use less expensive materials.

Abstract: A system that controls temperature in a heat recovery steam generator (HRSG). One heat recovery steam generator system may include a first exhaust path. The heat recovery steam generator system also may include a second exhaust path. The heat recovery steam generator system may include a first damper configured to selectively allow a portion of an exhaust to flow through the second exhaust path.

Abstract: A combined cycle power plant in which a gas turbine engine generates power, a heat recovery steam generator (HRSG) produces steam from high energy fluids produced from the generation of power in the gas turbine engine and a steam turbine engine generates additional power from the steam produced in the HRSG. The combined cycle power plant includes a heating element fluidly interposed between the steam turbine engine and the HRSG to heat fluid output from the steam turbine engine, which is to be fed to the HRSG and a control system to control an amount the fluid output from the steam turbine engine is heated by the heating element based on differences between HRSG and ambient temperatures.