| ZCT (Zero Current Transition) full-bridge DC/DC converter, realizes the ZCS of leading-legs and the ZCS of lagging-legs and overcomes some disadvantages of phase-shifted full-bridge zero-voltage and zero-current-switching (ZVZCS) converter,which has improved the condition of soft switch, has been attracted more and more attentions.A novel ZCT PWM full-bridge DC/DC converter is proposed in this paper .The principle of the novel converter is analyzed, and the foundations of parameter-design are presented. Futhermore, parameter calculation formulas at different modes are deduced. A simulation is performed successfully to analyze the converter's working characteristics using Pspice9.2. One 1.5KW ZCT soft-switching power supply based on this topology is developed, and the design process of main circuit, control circuit, protection circuit and high-frequency transformer are presented, and experimental results are also included in this paper.The novel ZCT PWM full-bridge DC/DC converter, Compared with the previously proposed topologies, a simple auxiliary circuit that consists of active switchings is used. The proposed converter not only achieves zero current switching for the main switches and auxiliary switch in the load ranges,but it also keeps the voltage stress less and realizes soft commution of the secondary rectifier diodes. Diode of auxiliary circuit is softly commutated and it's of reverse recovery is minimized. Furthermore,the transition has low conduction and switch loss, which guarantees high efficiency over wide load range.
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