SSA optimized PID controller for Three Area hybrid System for Load frequency control

In the present work, a Squirrel Search Algorithm-based PID controller is suggested for load frequency control of three area hybrid power systems consisting of thermal and hydro unit in area-l, wind and thermal unit in area-2, and diesel and thermal in area-3. Proportional integral and derivative (PID) controllers installed in each area have been optimally tuned to maintain the variation in frequency and tie-line power deviation within the schedule limits considering the effect of generation rate constraints. Two different cases have been investigated, in case-l GRC effect has not been considered and in case 2, the GRC effect has been included. Three intelligent optimization techniques named Squirrel search algorithm (SSA), Firefly algorithm, and Gravitational Search algorithm (GSA) have been implemented to obtain the optimazied gains of the PID controllers.