Application of SOS in fuzzy based PID controller for AGC of multi-area power system

This article presents an innovative idea to design a system based on fuzzy logic with PID controller for Automatic generation control (AGC) of a three equal area and each area having one thermal unit with reheat type turbine and a Generation Rate Constraint (GRC) of 3% per min is taken for each area. Various controllers like PI, PID and fuzzy-PID are used to improvise the change in frequency and tie-line power constancy of interconnected power system. The controller parameters are tuned by applying an interactive relationship between natural organism based optimization technique named Symbiotic Organism Search algorithm (SOS) technique and for this the required objective function ITAE. The variation step load by 1% is considered for area one only while other area doesn't have any load variation for this analysis. The deviation in system frequency and tie-line power signals of above said controllers are compared and it is seen that SOS technique based fuzzy-PID controller having excellent performance over other in regards for settling time, peak overshoot and undershoot with reduced oscillation.