Adaptive self-tuning PID fuzzy sliding mode control for mitigating power system oscillations

In this paper, an adaptive self-tuning PID fuzzy sliding mode controller (ASPFSM) with a PID switching surface is proposed to damp power system oscillations. To overcome the problems in the design of a sliding-mode controller, which are the supposition of known uncertainty bounds and the chattering phenomenon in the control effort, an adaptive self-tuning PID based Lyapunov theory is studied. An adaption law is obtained from the Lyapunov stability theory, so the stability of the closed-loop system can be guaranteed. Then, the effectiveness of the ASPFSM is studied under different situations of a two-area four-machine power system. The simulation results confirm that performance of ASPFSM is much better than conventional power system stabilizer (CPSS).