Optimized design of medium frequency transformers with high isolation requirements

For future DC electric power systems, high-power DC-DC converters will play a major role as they will substitute today´s bulky 50/60Hz transformers. One key component within this DC-DC converters is the medium frequency transformer that provides the isolation level and the step up/down of the different voltage levels. As a consequence, an optimized design methodology that considers this high isolation requirements is needed. This paper presents a step-by-step design for medium frequency transformers with high isolation requirements. Each step in the design is carefully discussed and the required design considerations, such as flux density limits, isolation and thermal management, are explained in detail. The proposed design procedure is applied to a core-type transformer analyzing the outcome of the optimization process.