High step-up current-fed ZVS dual half-bridge DC-DC converter for high-voltage applications

Abstract

In this study, a new high step-up current-fed zero voltage switching (ZVS) dual half-bridge DC-DC converter is proposed. The presented topology is composed of two paralleled boost half-bridge converters. In this converter, only two switches are efficiently utilised such that the adopted scheme has a simpler control circuit, lower losses and lower cost. It is very noteworthy that over the whole range of load and input voltage variations, the switches keep ZVS operation and the output diodes operate in zero current switching (ZCS) condition leading to high overall efficiency. Also, taking the advantage of voltage-doubler circuits, transformers with lower turn-ratio and diodes with lower reverse voltage can be used to build the desired high output voltage. Regarding the mentioned characteristics, the proposed converter can be well nominated for distributed generation systems. In-depth analysis, design and performance comparison of this new converter are illustrated; then for verification purpose, experimental results with an output voltage of 400 V and output current of 2.5 A are presented.