Determination of the capacity of grid connection points by grid impedance measurement

This contribution deals with the determination of the capacity of grid connection points in order to connect potentially more e.g. wind energy converters (WEC) to the grid. At first the determination of the short-circuit power at the fundamental frequency is outlined. Then the frequency characteristic of the grid impedance is analyzed. The focus lies on the identification of the grid impedance by measurement with a novel measurement container for the medium-voltage level. This grid impedance measurement container can be used to assess the capacity of points of common coupling (PCC) and also the harmonic emission of WEC.