High sampling rate digital excitation system controller with integral PSS control strategy

The author gives an overview of a digital excitation control system (ECS) and of some aspects of its recent application on 660 MW generators arising from modernising in a main line power station. The digital ECS in question is a dual channel automatic system with manual standby (open loop) mode. It performs all the tasks available in the analogue ECS it replaces in a single cycle of the complete program. The program includes as standard the system stabilising function which in case of the analogue ECS in UK practice was regarded as a supplementary control and was provided on request