Robust Pitch-Angle Control of Floating Offshore Wind Turbines Using Optimized Active Disturbance Rejection Control

This paper presents a robust pitch-angle control strategy for a floating offshore wind turbine (FOWT) based on an optimized active disturbance rejection controller (OADRC). The suggested controller uses the Red-Tailed Hawk (RTH) optimization algorithm to automatically adjust the ADRC parameters. This makes the system better at rejecting disturbances and more robust overall. The optimization process minimizes a multi-objective cost function that combines generator-speed and power-tracking errors with fatigue-load indices on the tower and mooring lines. A high-fidelity nonlinear simulation environment was established by coupling OpenFAST with MATLAB/Simulink to evaluate the controller performance. When compared to a standard ADRC and a gain-scheduled proportional–integral (GSPI) controller, the proposed OADRC shows big improvements. It cuts generator-speed fluctuations by 82.9%, torque error by 56.1%, and tower damage-equivalent load by about 19%. The results confirm that the optimized ADRC provides an effective and model-free solution for achieving robust power regulation and structural-load mitigation in floating offshore wind turbines.