Analysis of Thyristor-Controlled Shunt SSR Countermeasures

This paper presents the results of a study to compare the effectiveness of three SSR countermeasures. Both frequency and time domain techniques were used to insure the integrity of the investigation. Reactive power modulation with generator speed feedback will damp all SSR modes if phase lags associated with thyristor firing controls are compensated. It was also found that Graetz bridge devices can damp SSR oscillations in addition to their primary functions.