Method for starting a combined cycle power plant

摘要

A method for starting a combined cycle power plant (1) includes loading the gas turbine unit (2), providing a starting temperature (Tstart) for the steam supplied to the steam turbine (5), while the control valve (7) is regulated controlling the temperature of the steam at a temperature substantially equal to the starting temperature (Tstart) at a position (P2) downstream of the control valve (7) and upstream of the rotor (8), when the control valve (7) is substantially fully open, supplying steam to the steam turbine (5) at the starting temperature (Tstart). The steam temperature is controlled by controlling the steam temperature upstream of the control valve (7) in accordance with the temperature drop caused by the control valve (7) when the steam passes through it.

主权项

1. A method for starting a combined cycle power plant having a gas turbine unit and a steam turbine unit, the steam turbine unit having a steam turbine with a rotor and a control valve upstream of the rotor, the method comprising:
loading the gas turbine unit; determining a starting temperature (Tstart) for the steam supplied to the steam turbine; regulating the control valve from a closed position to an open position to admit steam into the steam turbine; controlling, via a control unit, the temperature of the steam during said regulating to a temperature higher than the starting temperature (Tstart) at a position (P1) upstream of the control valve, and a temperature substantially equal to the starting temperature (Tstart) at a position (P2) downstream of the control valve and upstream of the rotor; and regulating, via the control unit, a steam attemperator based on at least the steam temperature at the position downstream of the control valve and upstream of the rotor.