Fuel cell electric vehicles (FCEV) are emerging clean energy vehicles. A new soft switching current buck DC/DC circuit topology for FCEV was proposed. The characteristics and working process of the circuit topology were analyzed. By appending inductor, capacitor, diode in basic buck circuit, the converters main power switch and diode current were working in soft switching status, and the converters EMC and reliability were improved greatly. The circuit was simulated with Orcad software and its switch waveform, efficiency curve of 90kW DC/DC converter developed based on the topology was given. The converter has been used in the domestic fuel cell city buses successfully and proved to operate with reliability.
