Run-up of a combined power station by determining a load gradient of a gas turbine from parameters of a steam turbine

摘要

A combined power station 30 comprises at least one gas turbine 11 and one steam turbine 13, live steam for operating the steam turbine 13 being generated by means of the hot exhaust gases of the gas turbine 11 in a waste-heat boiler 16 and being fed to the steam turbine 13 and surplus live steam being guided via a controllable bypass line 24 and bypass valve 25 past the steam turbine 13 directly to a condenser 26. A cost-effective and environmentally friendly start-up method of operation is achieved if, in order to reduce the surplus steam flowing via the bypass, the gas turbine is initially run up to its minimum load, and if the gas turbine is subsequently run up with a load gradient (PSBGT/SB, fig 3) which is determined by parameter/parameters of the steam cycle, such as live steam temperature, bypass steam pressure, steam turbine flange temperature and/or bypass valve lifting measurement.