US Patent 7400055 Wind turbine generator

A wind turbine generator includes: a tower; a rotor supported by the tower to rotate around a rotational axis which is not parallel with an axis direction of the tower by wind power; a generator driven by a rotational force of the rotor; a sensor that detects vibration component in a direction perpendicular to the rotational axis of the rotor; and a control device that controls the rotor so that fluctuation of the rotor is caused to suppress the vibration component.