This article proposes a novel bidirectional isolated dc–dc converter with high voltage gain and wide input voltage, which can be applied to bidirectional power conversion systems. The proposed topology is composed of a bidirectional buck-boost converter and a forward-flyback converter; it has the advantage of higher voltage gain and has continuous current characteristic of the low-side port in step-up and step-down mode. In addition, the proposed topology also has the function of leakage inductance energy recovery, which can improve the efficiency of the converter, reduce the voltage surges on switches, and have the characteristics of zero voltage switching on certain switches. Finally, this paper implements a 500-W bidirectional dc–dc converter to verify the feasibility of the proposed topology. The low-side voltage of the proposed topology is 24, 48, and 55 V; the maximum efficiency in step-up mode are 94.2%, 95.6% and 96.9%, and the maximum efficiency are 92.6%, 94.2% and 94.5% in the step-down mode, respectively.

中文翻译：

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具有高电压增益和宽输入电压的新型双向隔离式DC-DC转换器

本文提出了一种新颖的双向隔离式DC-DC转换器，该转换器具有高电压增益和宽输入电压，可应用于双向功率转换系统。所提出的拓扑结构由双向降压-升压转换器和前向反激转换器组成。它具有较高的电压增益的优势，并且在升压和降压模式下具有低端端口的连续电流特性。此外，提出的拓扑还具有漏电感能量回收的功能，可以提高转换器的效率，减少开关上的电压浪涌，并具有在某些开关上零电压开关的特性。最后，本文实现了一个500W双向DC-DC转换器，以验证所提出拓扑的可行性。拟议拓扑的低端电压为24，48和55 V；升压模式下的最大效率分别为94.2％，95.6％和96.9％，降压模式下的最大效率分别为92.6％，94.2％和94.5％。