Design and Implementation of an Isolated Bidirectional Phase-Shift Full-Bridge Converter With High Transformation Ratio

In this paper, a bidirectional full-bridge phase-shift converter with high transformation ratio scheme is proposed. The main architecture of this converter is dual active full-bridge circuit. By using phase-shift modulation, the energy can be transmitted between high-voltage-side and low-voltage-side, and also can make the power switches have the function of soft-switching. This converter is designed with the transmission power of 1kW and the digital signal processor TMS320F28335 is utilized as the main system controller core. Finally, it realizes the bidirectional power conversion mechanism between battery 50
$\text{V}_{\mathrm {dc}}$
and DC grid 400
$\text{V}_{\mathrm {dc}}$
. The experimental results show that the maximum conversion efficiency of this converter when operating in the forward charging mode (G2V mode) is up to 92.25 %, and in the reverse discharging mode (V2G mode), the maximum conversion efficiency is up to 93.02 %. In comparison with the related studies for dual active full-bridge converters, the conventional transformation ratio is lower or equal to 4. This study with high transformation ratio can reach 8 for practical high-low voltage bidirectional applications. After the validation for both modes, the proposed concept is practical in the high transformation scenarios.