Cuckoo search algorithm based two degree of freedom controller for multi-area thermal system

Two-degree-of-freedom based Proportional plus Integral plus Double Derivative (2-DOF-PIDD) controller is designed and presented to solve the load frequency control (LFC) problem of a three unequal area thermal system. All the areas are equipped with single stage of reheat turbines and appropriate generation rate constraints (GRC). The performances of the proposed 2-DOF-PIDD controller are compared with the commonly used classical controllers such as I, PI and PID controller to assess the best supplementary controller for LFC. Selection of the optimum parameter of the several controllers and speed regulation (R) parameters are done by a new metaheuristic optimization algorithm called Cuckoo Search algorithm (CSA). The main advantage associated with CSA is that it has only two controllable parameters that make the algorithm less complex and thus potentially more generic. Numerous simulation results clearly show that proposed controller guarantees better performance over others in terms of settling time, peak overshoots and reduced oscillations. Further, robustness of CSA optimized 2-DOF-PIDD controller is tested against different position of perturbation. Proposed 2-DOF-PIDD controller also provides better performances when subjected to higher degree of perturbation.