Mitigating inter-area oscillation of an interconnected power system considering time varying delay

A wide area damping controller to mitigate the frequency deviation of interconnected power system is designed in this paper. The test system considered here is a two area power system. Each area in the test system has two generators. A linear matrix inequality (LMI) based state feedback control law is designed with the help of Lyapunov-Krasovskii functional. A thyristor controlled series capacitor (TCSC) is used to provide sufficient damping in the interconnected power system. A supplementary damping controller (SDC) is also used with the TCSC. The effect of time delay in the control signal is also considered in this paper for the two area four machine power system.