ABSTRACT
Wind turbines have control systems whose primary purpose is to keep the turbine operating states, i.e. the rotor speed, aerodynamic torque, generated power etc., at their wind speed dependent design values. However, as the size of wind turbines has increased, the demands on the controller have increased and its design task has become more demanding. For modern multi-MW turbines, the controller objectives now commonly include the reduction of structural loads, specifically, the loads on the tower and blades.
