SSR countermeasure impact on system induction-generator effect

Generalized transmission parameter equations are derived for the induction-generator (IG)-effect constraints on a system to which subsynchronous resonance (SSR) countermeasures of the active type are applied to control a torsional instability at a frequency that coincides with or is close to the synchronous complement of the electrical resonance frequency. The presence of the phenomenon under varying transmission topologies is analyzed, for typical system data, in a study carried out for two leading SSR remedial concepts: the dynamic stabilizer and the NGH scheme. IG-control by modulation phase angle in the stabilizer case and by a discrete capacitor discharge in the NGH scheme is postulated and analyzed