A Comparison of Zero-Voltage and Zero-Current Switching Phase-Shifted PWM DC-DC Converters

This paper presents a comparative study between an improved full-bridge (FB) zero-voltage and zero-current switching (ZVZCS) phase-shifted pulsewidth modulation (PS-PWM) DC-DC converter and an improved three-level (TL) ZVZCS PS-PWM DC-DC converter. Both converters operate at fixed frequency and achieve zero-voltage-switching on the leading leg of FB or outer switches of TL, and also achieve zero-current-switching on lagging leg of FB or inner switches of TL. To compare the improved FB-ZVZCS-PS-PWM DC-DC converter, the improved TL-ZVZCS-PS-PWM DC-DC converter is that the voltage across the switches is the half of the input voltage. In addition, the operational intervals and analysis are presented. Both prototypes operating at 30 kHz, rated at 300 V input voltage of FB and at 600 V input voltage of TL, and 1 kW output power at 42 V rated output voltage, have been constructed and tested in laboratory