Experience with Supplementary Damping Signals for Generator Static Excitation Systems

Virtually all hydraulic generating units installed in Ontario Hydro since 1964 have been equipped with static excitation systems, necessitating supplementary stabilizing signals to suppress power oscillations. This paper reviews the experience gained with alternative types of stabilizing systems at these stations and discusses advantages and disadvantages of each, problems in meeting accuracy requirements, permissible levels of noise content in the signals and the problems in application of stabilizing signals to thermal machines.