Control of a wind turbine having adjustable rotor blades

A method for controlling a wind turbine having rotor blades with adjustable blade angles, the method comprising:

• operating the wind turbine in a partial load mode for wind velocities up to a nominal wind velocity, wherein in the partial load mode:
• a first partial load angle is provided for the adjustable blade angle, and
• starting from a predetermined operating state, the adjustable blade angle is reduced as compared with the first partial load angle, and
• operating the wind turbine in a full load mode for wind velocities above the nominal wind velocity, wherein in the full load mode the adjustable blade angle is enlarged with increasing wind velocity and has values above the first partial load angle,
• wherein in the partial load mode, a power is set as a function of the rotational speed of a rotor of the wind turbine, and, starting from at least one of a predetermined rotational speed and a predetermined power, the adjustable blade angle is adjusted as compared with the first partial load angle, and wherein the adjustable blade angle is reset to the first partial load angle before the full load mode is reached, wherein sensors are provided to detect torsion of at least one of the rotor blades about its longitudinal axis, wherein the detected torsion is used as a criterion for adjusting the adjustable blade angle, and wherein the adjustable blade angle is adjusted to have a sharper rise as a value of the detected torsion increases.