Medium frequency transformer for traction applications making use of multilevel converter: small scale prototype test results

In the domain of electric traction, the demand for medium voltage supply systems of high power, compact size and reduced weight is growing. Thanks to the new semiconductors (HV-IGBT, IGCT) with high voltage capability, the multilevel topologies with medium frequency transformer become very attractive. Several solutions based on this principle were proposed these last years. In this paper a 10 kVA, four stages multilevel converter is presented. This solution seems particularly well adapted to the different requirements (volume, weight, EMC, loss) of the electric traction domain