Combined cycle power plant having supercritical steam turbine

摘要

A combine cycle power plant is presented. The combine cycle power plant includes a gas turbine, a heat recovery steam generator, a main steam turbine and a supercritical steam turbine. The supercritical steam turbine may be operated as a separate steam turbine that may be not a single steam turboset with the main steam turbine. The supercritical steam turbine receives supercritical steam generated in the heat recovery steam generator to produce power output. Exiting steam from the supercritical steam turbine may be routed to the main steam turbine. The supercritical steam turbine may be operated at a rotational speed that is higher than a grid frequency. The rotational speed of the supercritical steam turbine may be reduced to the grid frequency via a gearbox.