Fully Soft-Switched High-Efficient Bidirectional DC-DC Converter for Low-Power Applications

This paper presents a new bidirectional high-efficiency DC-DC converter, which realizes zero-voltage switching (ZVS) conditions for all semiconductors by utilizing an active clamp circuit comprised of two switches, a capacitor, and a small inductor which does not make the converter’s structure complicated. Low switching losses and EMI noise make it suitable for high switching frequency operation, which means high power density, in practice. Notably, the converter’s efficiency remains above $\mathbf{9 1 \%}$ across its entire power range in buck operation mode and exceeds $\mathbf{9 3 \%}$ in boost operation mode. It is notable to mention that the maximum efficiency of the converter reaches approximately $\mathbf{9 8 \%}$ in both buck and boost operation modes. The proposed converter has been simulated at 100 kHz switching frequency over wide operation conditions. Simulation results, clearly show that the proposed converter exhibits high efficiency even over an input voltage of buck operation mode (22-26) and boost operation mode (46-50) and wide load (5-160 W) variation ranges for both buck and boost operation modes.