Zero-voltage and Zero-current Switching (ZVZCS) Full-Bridge Three-Level DC/DC Converter

This paper proposes a new zero-voltage and zero-current switching (ZVZCS) full-bridge (FB) three-level DC/DC converter (TLDC) with the corresponding modulation strategy for the high-input-voltage and high-power applications. The merits of the proposed converter with the corresponding modulation strategy are concluded as follows. In comparison with the conventional zero-voltage switching (ZVS) FB TLDC, 1) only one blocking capacitor is added to realize ZVZCS; 2) the primary circulating current and duty cycle loss can be effectively reduced. In addition, the wide input voltage range can be satisfied because the proposed corresponding modulation strategy is composed of two working patterns. More significantly, the conduction losses of the primary power devices can be greatly reduced due to removing the primary blocking diode in comparison with other ZVZCS FB TLDCs. Finally, the simulation and experimental results are presented to verify the proposed converter with the corresponding modulation strategy.