A MULTIPHASE SERIES-RESONANT CONVERTER WITH A NEW TOPOLOGY AND A REDUCED NUMBER OF THYRISTORS

Multiphase series-resonant (SR) power converters provide a flexible wa y to transform power between a utility grid and a multiphase load or s ource. The current implementations all suffer from a high component co unt, which makes the use of these converters unattractive from an econ omical point of view. A new topology for multiphase SR converters has been proposed in the literature in a simulation context. This topology uses half the number of power semiconductors compared to the existing multiphase SR converters. The present paper addresses the implementat ion of the new topology in a prototype converter. The old and new topo logies are presented. The operation of the new topology is explained. In the new topology the resonant circuit is grounded at one side, whic h compared to the old topology imposes a restriction on the operation. The paper shows both simulation data and measured waveforms. It is ex plained that the economical gain due to the reduction in component cou nt is offset by a lower power rating. The paper finishes with conclusi ons and acknowledgments.