Abstract: A method for recording the magnitude and phase of electrical voltage in an electrical three-phase supply network for a fundamental and at least one harmonic is provided. The method includes measuring an electrical three-phase voltage of the supply network, transforming the measured voltage values into polar coordinates using a rotating voltage phasor for the fundamental as a measured reference phasor, and respectively observing values of at least one voltage phasor for the fundamental and of at least one voltage phasor for at least one harmonic to be recorded with the aid of a state observer, and tracking the observed values on the basis of the measured reference phasor.

Abstract: The invention concerns a wind power installation comprising a pod, a rotor, a first and/or second microwave technology and/or radar technology measuring unit for emitting microwaves and/or radar waves and for detecting the reflections of the microwaves and/or radar waves to acquire wind data and/or meteorological data or information in respect of a wind field in front of and/or behind the wind power installation, and a control means of the wind power installation, which controls operation of the wind power installation in dependence on the data detected by the first and/or second measuring unit.