Intelligent power system stabilizers using fuzzy logic technique and sliding mode control strategy

Abstract

Each electric power grid should be equipped with a power system stabilizer (PSS) to ensure the network stability during operation and distribution. The major function of a PSS is to provide an appropriate control signal to the synchronous generator system, making its rotational speed stabilization against disturbances. This paper investigates three control strategies to design such an efficient PSS for the power network, including a PID-based PSS, a fuzzy logic – based PSS (FLC), a fuzzy logic-integrated sliding mode control – based PSS (SMC). With the rapid development of fuzzy logic technique considered to be an intelligent and successful control tool, the PSS controllers applying this control strategy are able to obtain good control performances, satisfying high requirements of the smart grids. Through a number of numerical simulations implemented in MATLAB/Simulink package for a single synchronous generator connected to an infinite bus, this work verifies the feasibility and success of the studied control strategies in designing an efficient PSS controller. Two case studies with load change and without load change will also be carried out in this paper to demonstrate the broad stability range of the proposed PSS controllers. Simulation results reveal that the FLC and the SMC are much better than the conventional PID-based PSS controllers and these two intelligent regulators can be selected for successfully solving the stabilization problem of an electric power grid in practice.