Stabilization of inter-area modes by controllable phase shifter

This paper presents an application of a fast, fully controllable phase shifter (CPS) for stabilizing unstable or poorly damped inter-area oscillatory modes in an interconnected system. The study is based on eigenvalue analysis of a linearized interconnected system model. Inter-area modes are first identified for an oscillation incident and then stabilization of these modes using a CPS is obtained. The best location for installing a CPS is determined by analyzing the mode controllability. A decentralized control scheme using tie line power deviation as the feedback signal for the CPS control system is shown to be effective in damping inter-area modes of oscillation. Computer simulation of an interconnected study system is used to validate the proposed CPS controller