Zero-voltage zero-current switching full bridge PWM converter with reduced filter size

An improved zero-voltage zero-current switching (ZVZCS) full bridge PWM converter is proposed in this paper. The proposed converter consists of two full bridge inverters in the primary side and two rectifiers in the secondary side and total power is equally distributed to each inverters and rectifiers. Also a primary current of transformer winding is naturally reset by input source. Therefore, zero-voltage switching for the leading leg switches and zero-current switching for the lagging leg switches are achieved without requiring any additional components and distributed total power increases reliability of the system. Furthermore, multi-level voltages shown at output filter reduce the filter size. The operational principle and analysis of the proposed converter are presented and verified by 700W prototype.