Active Damping Control and Load Mitigation of Wind Turbines Based on State Feedback

With the increasing importance of wind energy in the global power market, more stringent performance requirements are being placed on wind turbines. However, most existing control strategies neglect the active damping effects of blade pitch and generator torque, which may result in increased structural loads and reduced system reliability. In this study, an active damping control strategy is proposed that simultaneously incorporates both pitch and torque contributions. A comprehensive mathematical model is developed, and an <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{H}_{2} / \mathrm{H} \infty$</tex> mixed sensitivity control method is employed. The controller parameters are further optimized using intelligent algorithms. Simulation tests based on the National Renewable Energy Laboratory (NREL) 5-MW reference wind turbine and its open-source (ROSCO) controller demonstrate that the proposed method significantly reduces power and load fluctuations under turbulent wind load conditions, thereby enhancing the dynamic performance and operational reliability of the wind turbine system.