Application of PSS and FACTS devices for damping low frequency oscillations in power systems

Abstract

Stability of power systems has been and it will continue to be the major concern in power system operations due to power system oscillations caused by complex interconnections. Efforts have been attracted towards damping the power system oscillations for enhancing stability in power systems. The instability that has been affected by the complex interconnections is the small signal stability. Power system stabilizers (PSS) are promising in damping small signal stability. Although, PSS are confronted with some drawbacks of serious variation in the voltage profiles and it may also results in leading power factor operations which may cause reduction of system stability under heavy disturbances. In large multimachine power systems, the application of only conventional PSS may cease to provide adequate damping for inter-area oscillations and effect of variation in voltage profile. However, power electronic device known as Flexible Alternating Current Transmission System (FACTS) devices are effective in damping the inter-area oscillations and capable of handling the variations in voltage profile. Therefore this paper presents a comprehensive review and evaluation of PSS and FACTS power oscillation damping (POD) controllers in mitigating low frequency oscillations based on computational intelligence methods. Technical paper publications on design, optimal location and optimal parameter tuning associated with PSS and FACTS based controllers are highlighted. Finally the potential future research directions for novel PSS and FACTS devices is proposed as a reference for interested researchers