Steam turbine-generator operation and maintenance

THE Southern California Edison Company, with approximately 2,187 megawatts (mw) of effective operating capacity, 52 per cent of which is steam driven, is a participant in the 8,800-mw Pacific Southwest power area. In this operating area, the load changes on the systems and interchange of power across the interconnecting ties will on occasion impose rate-of-generation changes of 25 to 30 mw per minute, for periods of relatively short duration. The control of the tie line load and combined system frequency is maintained by automatic load- and frequency-control equipment, with one system regulating frequency, and the remaining systems controlling their ties with the regulating system.