Background harmonic distortion measurement at power networks with wind farms

Abstract

Standard IEC 61400-21 specifies that background voltage distortion must be lower than the threshold limits specified in standards. However, this background distortion information is not used for calculating the real harmonic emission from the wind turbine leading to misleading voltage harmonics assessment from the wind turbine. In this paper a methodology for assessing the real harmonic emission from wind turbines is proposed based on current and voltage measurements where the background harmonic distortion at the Point of Common Coupling is considered.