Modern soft-switching topology for galvanic insulated railways auxiliary converter

A high-efficiency high-frequency link inverter design with bi-directional power flow, using a zero-voltage-switching (ZVS) technique is proposed. The considered configuration includes a HF full-bridge inverter, a HF transformer, a 3-phase cycloconverter; Required bidirectional switches have been composed by anti-series IGBT connection. Main advantages of the topology are weight and size reduction, by elimination of intermediate filter and reduction of number of stages. A novel digital control strategy is presented, and performances are evaluated by means of numerical simulation, showing its effectiveness.