High voltage Auxiliary Power Supply with the simplified power circuit topology for the DC trains

The paper proposes a simplified power circuit topology for the auxiliary power supplies (APS) with output powers up to 50 kW to be used in 3.0 kV DC commuter trains. Focus is on the implementation of 6.5 kV IGBTs to improve power density, system integrity as well as the reliability of the APS. For instance, a topology proposal, an analysis and a comparison with other types is presented. Some problems of converter control and protection as well as hardware design considerations are discussed. Efficiency estimation of the new topology and some recommendations of loss minimization are given.