Efficient Self-Tuned Fuzzy Logic Based Power System Stabilizer

Abstract

A mechanism for efficient self-tuning of a fuzzy logic-based PSS in real-time is presented. The proposed controller with a self-tuning mechanism can reduce low-frequency oscillations regardless of magnitude or type of disturbance, whether sudden or gradual. It is not necessary to set the initialization or learning factor for each disturbance and its implementation is simple. Speed deviation and its derivative are used as fuzzy controller inputs. The main idea, based on the properties of the conventional PID controller, is to use a fuzzy controller similar to a PID controller but for the nonlinear power system. Since the objective is implementation on a physical system, nonlinearity without any simplification of the system is very important. Therefore, in this mechanism, the full order machine model is considered. The optimal performance is obtained by determining in real-time the appropriate gains for each input. Tests for a wide range of disturbances show the robustness of the controller. The proposed approach has fewer fuzzy rules than similar methods. Therefore, its hardware implementation can be simpler and will require less computation time. Very good damping of all types of disturbances is a prominent feature of this method.