Wind Energy Conversion Systems as active filters under unbalanced load conditions

The present paper investigates the performance of a Wind Energy Conversion System controlled to operate as an Active Filter when unbalanced loads are supplied by the same feeder. The control strategy named `compensation by means of Combined Modulation´ is applied. This control methodology has been designed to sink the harmonic currents injected by balanced Non-Linear Load, and the connection of unbalanced loads to the PCC results in additional harmonic current flows within the WECS components and other detrimental effects. This paper is intended to analyze these effects and to determine the unbalanced load conditions that can be withstood by the WECS without compromising the components´ integrity.