Improvement power system stability using Unified Power Flow Controller based on hybrid Fuzzy Logic-PID tuning In SMIB system

The paper presents hybrid fuzzy logic - PID tuning controller for damping low frequency oscillations using Unified Power Flow Controller (UPFC) applied on a single-machine infinite-bus (SMIB) system. The intention of the Fuzzy Logic based UPFC controller is to damp power system oscillations. UPFC controller depend upon amplitude modulation index of shunt converter (exciter) mE. So this index has been considered. System response with Damped-UPFC controller without fuzzy logic and PID-fuzzy logic (using mamdani-type inference) based UPFC controller is compared at various conditions of power system. Relevant models have been developed and simulated in Matlab/Simulink R2013a. The hybrid PID-Fuzzy Logic based UPFC controller is designed by selecting appropriate controller parameters based on the facts of the power system performance. All studies show that the PID-fuzzy logic controller has an excellent capability in damping low frequency oscillations.