Analysis and Design Consideration of a Current-Fed ZVZCS Phase-Shifted Full-Bridge Converter

A new current-fed rectifier based phase-shifted full-bridge (PSFB) converter is proposed in this paper to be suitable for the electrical vehicle application, where the load range is wide and high output voltage is required. The converter can achieve effectively zero-voltage switching (ZVS) for the leading arm and zero-voltage zero-current switching (ZVZCS) for the lagging arm in the whole load range. Compared with the conventional PSFB converter, the presented converter can eliminate the voltage spikes and reverse recovery losses across the output-diodes. It has many remarkable advantages such as simple auxiliary circuit, no duty cycle loss and no energy snubber circuit at secondary side. The operational principle and analysis of the proposed converter are presented and optimum design considerations for some key parameters are also given. To validate the feasibility of the presented topology, a 1kW/300V, 100kHz prototype is implemented and tested.