Enhancement of Damping of Power System Oscillations through UPFC Placement based on Residue Factor and Critical Modes

In this research, placement of UPFC is presented on dynamic stability by using the residue factor and critical modes of power system. The placement by using critical modes determines the requirement number of UPFC to enhance damping of power system oscillations. The supplementary controller is used to control UPFC The input signal for this controller is selected based on the participation of the generators speed state variables in the critical modes of power system. The effectiveness of UPFC in power system stability enhancement are demonstrated on IEEE 9-BUS system by drawing the speed and angle deviations curve of generators, the system poles locations and Bode diagram.