Design of a Fuzzy Logic Controller to Enhance Power System Small Signal Stability

A reliable and continuous supply of electric energy is essential for efficient functioning of the modern sophisticated society. Due to a combination of burgeoning energy consumption and impediments to increasing generation and transmission capacity, utilities are forced to operate the power systems ever closer to system stability limits. This in turn necessitates use of special control aids to improve damping of low frequency electromechanical oscillations. This paper presents development of a fuzzy logic based power system stabilizer to maintain stability and enhance closed-loop performance of a power system under disturbances. The proposed fuzzy controller is trained with an optimal controller designed by the current researchers. The effectiveness of the proposed fuzzy controller in a single machine infinite bus power system is demonstrated under a wide range of system and test conditions. Its performance is compared with that of a conventional lead-lag power system stabilizer and the designed optimal controller. Computer simulation studies show that the proposed fuzzy controller outperforms and improves the system damping compared to the conventional and optimal controllers