TIE LINE POWER OSCILLATION CONTROL IN AN INTERCONNECTED SYSTEM USING TWO LAYERS FUZZY LOGIC CONTROLLERS WITH UNIFIED POWER FLOW CONTROL

This paper focuses on systematic approach towards damping the tie - line power oscillations in an interconnected thermal power plant using Unified Power Flow Controller (UPFC) with two layer fuzzy logic controller (FLC). Conventionally, Automatic Generation Control (AGC) is carried out by primary governor control and secondary Proportional - Integral (PI) controller. PI controller helps to damp out tie - line power and frequency oscillations when subjected to unit step load disturbance. UPFC based damping controller helps to stabilize the tie - line power oscillations of power system. The simulation indicates reduced frequency and tie - line power transient with much f aster settling time is obtained by using UPFC along with two layer fuzzy logic controlled.