Performance of power system stabilizers in a fixed series capacitor compensated system

In this paper, the performance of two IEEE-type power system stabilizers (PSS), i.e., a slip-signal PSS and a Delta-P-Omega PSS are studied in a fixed series capacitor compensated system employing the IEEE first benchmark system. An eigenvalue analysis of the well-known slip-signal-torsional interaction showed that the slip-signal-interactions occur only when the degree of line compensation is above a certain level depending on the loading condition. The time-domain verifications of the eigen-predictions are carried out through modal speed plots instead of a confusing participation factor-based method. Further, the swing-mode damping performances of PSS are analyzed for different levels of series compensation. This study not only validated the poor swing-mode damping performances of a slip-signal PSS, but also demonstrated that a Delta-P-Omega PSS does not worsen the damping of swing-mode even at higher levels of series compensation which permits a straight forward PSS design.