Transformer Inrush Currents in a NPC Based Converter System for Cold Ironing Applications

In this paper, the effects of the transformer inrush currents in a real plant for Cold Ironing, with a power equal to 11 MVA, based on a conversion system using 4 NPC converters in parallel is presented. The first part describes the plant and the related problems, while in the second part two possible solutions are presented with the support of real measured data.