Design considerations of medium-frequency power transformers in HVDC applications

Abstract

High-power isolated DC-DC converters are likely to provide solutions for many technical challenges associated with power density, efficiency and reliability in potential applications such as offshore wind farms, inter-connection of DC grids and in future solid-state transformer applications. The medium-frequency power transformer (MFPT) is one of the key elements of such a converter to realize the voltage adoption, isolation requirements, as well as high-power density. This paper presents an overview of the most important design and optimization considerations of MFPTs taking into account the high-frequency magnetic losses and thermal management.