EID Estimator-Based Adaptive Periodic Event-Triggered Load Frequency Control for Hybrid Power System

Frequency deviations from nominal values can cause grid stress and overvoltage issues. To address this, this study proposes a filtered fractional-order PID controller (FOPIDn) for load frequency control (LFC) in networked power systems with renewable energy integration. System robustness is enhanced using an equivalent-input-disturbance (EID) estimator to suppress both periodic and aperiodic disturbances, while an adaptive periodic event-triggered mechanism (APETM) is employed to limit communication and energy consumption. The controller parameters are optimized using the Grey Wolf Optimization algorithm. Simulation and comparative results confirm that the proposed FOPIDn-EID-based LFC with APETM achieves superior frequency regulation, with minimal settling time and overshoot, outperforming COA-PI, COA-PIDn, and ABC-PIDn schemes. In addition, the APETM reduces triggering events to 33 compared with 42 for PETM, demonstrating improved communication efficiency.