Abstract

This paper presents the application of UPFC to enhance damping of Low Frequency Oscillations at a Single-Machine Infinite-Bus (SMIB) power system installed with UPFC. Since UPFC is considered to mitigate Low Frequency Oscillations (LFO), therefore a supplementary stabilizer controller based UPFC like power system stabilizer is designed to reach the defined purpose. Artificial intelligence methods such as Fuzzy logic schemes and Genetic Algorithms (GA) optimization are considered to design UPFC supplementary stabilizer controller. To show effectiveness and also comparing these two methods, the proposed methods are applied and simulated. Several linear time-domain simulation tests visibly show the validity of proposed methods in damping of power system oscillations. Also simulation results emphasis on the better performance of Fuzzy method compare to GA method. Simulations are carried out in MATLAB software.

Key words: Flexible AC transmission systems, unified power flow controller, damping power system oscillations, fuzzy logic, genetic algorithms.