A Grasshopper Optimization Algorithm based Control Strategy for LVRT Capability Enhancement of Grid-Connected DFIG-WECS

This work proposes a novel application of the grasshopper optimization algorithm (GOA) in this research work to enhance the low voltage ride-through (L VRT) capability of the grid-connected doubly fed induction generator (DFIG) based wind energy conversion system (WECS). The GOA is proposed in this article due to its faster convergence speed, low computational burden, and simple design. The proposed GOA update the gains of all proportional-integral (PI) controllers through rapid convergence speed. The optimal PI controllers are designed by the proposed GOA. Four PI controllers are applied in the rotor side converter (RSC), and another four PI controllers are employed in the grid side converter (GSC) under the cascaded structure. The DFIG is integrated into the grid through RSC and GSC with a common dc-link capacitor. The RSC is controlled to minimize the generator power loss and achieve the maximum power output using cascaded structure-based PI controllers, whereas GSC is regulated to maintain the dc-link voltage and grid side reactive power. The validity of the proposed GOA-PI controllers is verified by comparing the results with particle swarm optimization algorithm (PSO) based PI controllers under severe grid disturbances. The L VRT capability is performed using the MATLAB program.