Implementation of coordinated multiple facts controllers for damping oscillations

A linear optimal controller is designed to implement multiple Variable Series Compensations (VSCs) devices in transmission network of interconnected power systems. The proposed controller is utilized to damp inter-area oscillations and enhance power system damping during large disturbances. The effectiveness of the linear optimal controller to properly control such devices is demonstrated for a two-machine power system. Results from (i) digital simulation studies using a PSCAD/EMTDC software package, and (ii) real-time digital simulation studies using a PSCAD/RTDS, are discussed. The simulation results show that the controller contributes significantly to the damping of inter-area oscillations and the enhancement of power system damping. Moreover, the results of these different simulation studies agree quite well showing little discrepancies between them.