Background: Automatic Generation Control (AGC) of multi-area nonlinear power system
integrated with wind energy based Renewable Energy Conversion System (RECS).
Methods: A fuzzy PID controller has been proposed for AGC of a three equal area thermal system
integrated with RECS. Different physical nonlinear constraints like Governor Dead Band (GDB) and
boiler dynamics are introduced in the model for realization of non linear and realistic of proposed
multi area power system. To determine the optimum gain parameter, a Modified Symbiotic Organism
Search (M-SOS) algorithm has been used along with a fitness function which based on Integral
of Time Multiplied Absolute Error (ITAE).
Results: For performance analysis, the performance of proposed M-SOS optimized fuzzy-PID controller
is compared with PI, PID and fuzzy PI controllers. For technique comparison, performance of
proposed M-SOS technique is compared with original SOS and conventional PSO algorithms. Robustness
of proposed controller has also been verified by varying applied load and system parameters.
Conclusion: It is observed that M-SOS technique exhibits improved performance over original SOS
and PSO algorithms. It is also observed that proposed Fuzzy-PID controller provides better system
performance than PI, PID and fuzzy PI controllers. It has been observed that the proposed M-SOS
tuned fuzzy PID controller improves settling time of frequency response in area 1 by 11.30%, 15%
and 17.75% compared to M-SOS tuned fuzzy PI, PID and PI controllers respectively. Significant
improvements in settling time, peak overshoot and peak undershoot of the frequency response in
area 2 and tie line power are observed with the implementation this proposed approach.