Torsional interaction between an SSSC and a PSS in a series compensated power system

The extent and nature of control interaction between a power system stabiliser and a static synchronous series compensator (SSSC) has been studied. Countermeasures are suggested to reduce such interactions. The study system considered is the IEEE first benchmark model for subsynchronous resonance. The SSSC is used as a fixed compensator and the DC-link voltage of the SSSC is regulated by a simple PI controller. Stability of the system is determined from eigenvalue analysis. Nonlinear simulations are performed to verify the results of eigenvalue analysis.