ZVS-ZCS Bidirectional Full-Bridge DC-DC Converter

A bidirectional zero-voltage-switching (ZVS) and zero-current-switching (ZCS) full-bridge dc-dc converter is proposed in this paper. The proposed full-bridge converter topology with low ripple input current, which converts the energy from battery to DC bus (or load) and vice versa. In order to improve the overall efficiency, the proposed bidirectional converter uses the leakage inductance of the transformer and a capacitor to achieve circuit resonance. The resonant frequency is operated in about double frequencies of the primary switch. In this paper, the main switches and output synchronous rectifiers are operated in ZVS and ZCS when being switched on and switched off. Converter description and operating principles of the proposed converter are discussed in this paper. Finally, a laboratory prototype with output power 250W in both buck/charge operation mode and boost/discharge operation mode is implemented to validate the theoretical analysis.