Adaptive Symbiotic Organism Search Algorithm Optimized 3DOF-PID Controller for Load Frequency Control of Hybrid Power System

This work investigates the dynamic performance of a hybrid energy distributed power system (HEDPS) against constant and variable load perturbations. The HEDPS comprises renewable energy resources coordinated with a multi-unit hydrothermal power plant. To alleviate the frequency and power deviation against intermittent outputs of renewable energy resources, 3 degree-of-freedom (3-DOF) proportional-integral-derivative (PID) has been proposed. The results obtained with 3DOF-PID controller are compared with 2DOF-PID, PID, and PI controllers to quantify the effectiveness of the same. Symbiotic organism search (SOS) algorithm is applied to search the controller gains mentioned above. An adaption scheme in the generation of benefit factors has been considered to ensure balance between exploration and exploitation phases of SOS algorithm. The tuning competence of the adaptive SOS has been shown over SOS and other swarm intelligence algorithms. The inspection of the results demonstrates that adaptive-SOS tuned 3DOF-PID controller delivers comparatively better result than its other counterpart. Finally, sensitivity analysis is performed to affirm robustness of the developed controller by varying system parameters and loading condition.