A Compact DC-DC Converter for Offshore Wind Farm Application

Abstract

A DC-DC converter suitable for the grid integration of windfarms through a DC grid is presented. The operation is based on the Marx principle where charged capacitors are connected in series and parallel in turn to achieve the voltage transformation. The two inductors at the two ends of the converter are designed to resonate with the capacitors to create resonance forcing current zeros to enable zero current switching thereby reducing switching losses. The design of a 50 MW, 6kV/30kV DC-DC converter was carried out by analysis and simulation.