A survey of harmonic emissions of a commercial operated wind farm

In this paper, harmonic voltage and current measurements performed at the point of common coupling (PCC) of a commercially operated wind farm comprising of 40 variable speed wind turbines are analyzed, and their most important characteristics are presented. Important issues under consideration are characteristics of measured harmonic spectrum; the effect of the application of grouping calculation method, according to IEC 61000–4–7; the inter-harmonic problems; and the probability distribution of harmonic magnitude. In addition, an investigation of the separation for wind farm and grid contributions of the harmonic distortion at the PCC is included. Finally, the dependence of harmonic emission on wind farm output power is addressed.