This paper presents a family of soft-switching DC-DC power converters, which is suitable for high power applications using IGBT's. These converters present the following characteristics: Commutation at zero-current (turn-on and turn-off) for all active switches without overvoltage and overcurrent, commutation at zero-voltage for the free-wheeling diode and PWM operating at constant frequency. Small power rated auxiliary components can be used To verify the feasibility of the proposed family of soft-switching DC-DC power converters, the ZCS-PWM Boost Converter is analyzed. Operating principle, commutation analysis and features are described and verified by experimental results obtained from a prototype operating at 40 kHz, rated at 155 V input voltage and 1.1 kWatts output power. The measured efficiency to full load was about 98%.