Asymmetrical ZVS-PWM Switched-Capacitor Based Half-Bridge DC-DC
Converter With Switch Peak Voltage of Vin/2
Abstract
This paper presents a new power converter topology
generated by the integration of the asymmetrical ZVS-PWM dcdc converter
with a switched-capacitor ladder-type commutation
cell. Circuit operation and theoretical analysis with emphasis on
the soft-commutation process are included in the paper. The
main advantage of the proposed converter with respect to the
conventional asymmetrical half-bridge dc-dc converter is the
reduction of the voltage stress across the power switches to the
half of the input dc bus voltage, enabling the utilization of lower
voltage rating components. Experiments conducted on a
laboratory prototype with 1.4 kW power-rating, 800 V input
voltage, 48 V output voltage and 100 kHz switching frequency
are included, to verify the theoretical analysis and the design
methodology. The maximum efficiency of the experimental nonoptimized
prototype was 93.6%.
Index Terms - Asymmetrical dc-dc converter, pulse-widthmodulation,
switched-capacitor, zero voltage switching.