Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, a generator, a gearbox, a nacelle, and a rotor including one or more rotor blades. The rotor blades capture kinetic energy from wind using known foil principles and transmit the kinetic energy through rotational energy to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
During operation, the direction of the wind which powers the wind turbine may change. The wind turbine may thus adjust the nacelle through, for example, a yaw adjustment about a longitudinal axis of the tower to maintain alignment with the wind direction. In addition, wind turbines typically use pitch control to maintain rated power in high winds. As wind speeds increase, the blades are “pitched to feather” (i.e. the pitch angle of the rotor blades is increased) to reduce lift and thrust and maintain torque and power of the wind turbine. When the rotor blades pitch excessively in high winds, aerodynamic blade noise can be increased as well, as a result of thickened boundary layers or separated flow on the pressure side surfaces of the rotor blades.
Accordingly, it would be advantageous to limit excessive pitching and avoid an undesired associated noise increase. As such, the present disclosure is directed to systems and methods which actively yaw the nacelle of the wind turbine away from the nominal wind direction at high wind speeds. With the turbine yawed out of the wind, there is less available power and the blades will not be forced to pitch as excessively to maintain rated power.