Abstract: A method for detecting an accretion of ice on a rotor blade of a rotor of a wind turbine is provided. The can be operated at a variable rotational speed. The method includes recording a wind speed of a wind acting upon the rotor, recording an operating variable that is dependent on the wind speed and comparing the recorded operating variable or the recorded wind speed with a reference variable of a characteristic wind-speed-dependent operating-variable curve of the wind turbine. The characteristic operating-variable curve indicates an operating variable assumed to be optimal in dependence on the wind speed. The method includes detecting an accretion of ice on the rotor blade if the recorded operating variable or the recorded wind speed, deviates from the reference variable by at least a predetermined minimum deviation specified in dependence on the wind speed.

Abstract: A method for detecting an accretion of ice on a rotor blade of a rotor of a wind turbine is provided. The can be operated at a variable rotational speed. The method includes recording a wind speed of a wind acting upon the rotor, recording an operating variable that is dependent on the wind speed and comparing the recorded operating variable or the recorded wind speed with a reference variable of a characteristic wind-speed-dependent operating-variable curve of the wind turbine. The characteristic operating-variable curve indicates an operating variable assumed to be optimal in dependence on the wind speed. The method includes detecting an accretion of ice on the rotor blade if the recorded operating variable or the recorded wind speed, deviates from the reference variable by at least a predetermined minimum deviation specified in dependence on the wind speed.

Abstract: A method of controlling a wind power plant for generating electrical power from wind is provided. The plant comprises a rotor having rotor blades with adjustable blade angles and the rotor can be operated at a variable rotational speed. The method includes controlling the plant in a partial load mode when wind speed is below a nominal speed and, controlling the plant in a storm mode when the wind speed is above a storm commencement speed. An output power of the plant in the partial load mode and storm mode is adjusted according to an operating characteristic curve that determines a relationship between the rotational speed and the output power. A partial load characteristic curve is used as the operating characteristic curve for controlling the power plant in partial load mode, and a storm mode characteristic curve is used as the operating characteristic curve for controlling the plant in storm mode.

Abstract: A method of controlling a wind power plant for generating electrical power from wind is provided. The plant comprises a rotor having rotor blades with adjustable blade angles and the rotor can be operated at a variable rotational speed. The method includes controlling the plant in a partial load mode when wind speed is below a nominal speed and, controlling the plant in a storm mode when the wind speed is above a storm commencement speed. An output power of the plant in the partial load mode and storm mode is adjusted according to an operating characteristic curve that determines a relationship between the rotational speed and the output power. A partial load characteristic curve is used as the operating characteristic curve for controlling the power plant in partial load mode, and a storm mode characteristic curve is used as the operating characteristic curve for controlling the plant in storm mode.