METHOD AND SYSTEM FOR CONTROLLING A DC LINK VOLTAGE OF A POWER CONVERTER CONNECTING AN ELECTRIC GENERATOR OF A WIND TURBINE WITH A POWER GRID

摘要

A method is provided for controlling a DC link voltage of a power converter connecting an electric generator of a wind turbine with a power grid. The method includes determining the rotational speed of a rotor of the electric generator. The method further includes determining a strength of harmonic components of the rotational speed of the rotor, wherein the harmonic components have frequency components being different from a fundamental rotational frequency of the electric generator. The method also includes determining a damping reference signal as a function of the determined strength of the harmonic components, and controlling the DC link voltage of the power converter in response to the determined damping reference signal. A corresponding control system is also provided.