Comparison of the effectiveness of PSS and SVC in damping of power system oscillations

Power system stabilisers (PSSs) have been employed as the first choice to improve damping and extend system transfer capabilities. However, a problem with a PSS is that its performance is strongly dependent on the power network and its interconnections. Apart from PSS, static VAr compensator (SVC) can be also used for damping improvement. This paper presents analysis performed to compare the effectiveness of PSS and SVC in damping power system oscillations under different system operating conditions. It is concluded that a SVC properly tuned for one operating condition can provide good damping of system oscillations and good voltage control over a wide range of system operating conditions. The results emphasise better effectiveness of a SVC than a PSS in damping power system oscillations and voltage control.