GOA-Optimized Hybrid PDN (α+PI) Controller for Load Frequency Control in a Three-Area Power System with EVs

The increasing integration of renewable energy sources (RES) has intensified frequency fluctuations in interconnected power systems, requiring robust and reliable Load Frequency Control (LFC) strategies. This work introduces a new controller structure, referred to as the filtered PD cascaded with α-scaled PI control (PDN (α+PI)), whose parameters are optimized using the Grasshopper Optimization Algorithm (GOA). Its performance is evaluated against three benchmark techniques: the GWO-based PI PD controller, the ARA-based PID controller, and the COA-based PIDN controller. Simulation results for a three-area system demonstrate that the proposed GOA: FPN (α+PI) controller achieves superior dynamic performance across all load disturbances. In Area 1, it limits the peak frequency deviation to approximately 0.003 Hz, compared with 0.015 Hz, 0.23 Hz, and 0.25 Hz obtained using GWO, ARA, and COA, respectively. Tie-line power deviations are similarly minimized to about 0.5×10-6 pu, significantly lower than those produced by the other methods. The proposed controller consistently demonstrates faster settling times, reduced overshoot and undershoot levels, and enhanced robustness, making it a promising solution for frequency regulation in renewable-rich multi-area power systems..