Date Added: Feb 2011
UPFC devices are used to improve real power, reactive power, improve bus voltage and eliminate line loses in ac systems. An additional task of UPFC is to enhance transmission capacity as result of power oscillation damping. This paper use Relative Gain Array (RGA) for analyzing the interactions among the UPFC inputs/ output signals. RGA analyses for UPFC inputs with power oscillation damping controller and without POD controller are treated based on the Multi-Input Multi-Output (MIMO) transfer function matrix. With the help singular value and RGA, the dynamic input-output interactions are also analyzed. Then, the input signals for supplementary controller for oscillations damping is selected. A two area four machine power system with different operational conditions is simulated for the validations of the proposed approach.