Spectral monitoring based fuzzy logic stabilizer for multi-machine power system

Power system stabilizers (PSSs) are used to damp the electromechanical oscillations of the synchronous generators subjected to different types of disturbances. This paper introduces new stabilization technique based on fuzzy logic with gain switching capability. This capability enables the stabilizer to switch its input gains based on the disturbance level, which is determined by means of the power spectral density of oscillatory modes. A multi-machine model has been used to test the proposed switching fuzzy logic stabilizer (SFLS). The simulation results show the efficiency of the proposed stabilizer over a wide range of disturbances. The SFLS provides performance better than a simple fuzzy logic stabilizer for small and large levels of disturbances.