Design of high-current converters with Inter-cell Transformer

The coils power supplies employed for nuclear fusion energy reactors are built with a parallel connection of several power electronics converters to satisfy the very large current demand (≈30-50 kA). Such a parallel connection to the load is usually operated by inductors, whose size is quite critical since it is subject to the same converter current rating. To reduce the power supply volume, the paper proposes a comparison between inductors and inter-cell transformers. With reference to the specifications of coil power supplies under development for the Divertor Tokamak Test facility, this paper illustrates the modeling and the performance of the converter including inductor and two categories of inter-cell transformers. A volume comparison between the traditional solution and alternative options, including intercell transformers, is provided, having considered the same dynamic performance. The presented results are further validated through a Hardware-in-the-loop test facility.