Low Frequency Oscillations Damping by UPFC with a Multi Stage Fuzzy and Supplementary Controllers

Low frequency electromechanical oscillations are inevitable characteristics of power system which affect the transmission line transfer capability and the system stability. In this work, a new POD controller with DC-voltage regulator based on genetic algorithm is proposed for the UPFC for damping low frequency oscillations. The construction and implementation of this controller is fairly easy, which can be useful in real world power system. The effectiveness of the proposed controller has been tested on a SMIB power system in comparison with conventional UPFC controllers, GAMSF DC-voltage regulator and PSOMSF DC-voltage regulator under different operating conditions.