Conventional current-fed resonant converter suffers from high turn-off loss over wide range of fuel-cell voltage. To alleviate this problem, we propose high voltage gain current-fed resonant converter that achieves almost ZVS turn-off over a wide range of voltage gain. By employing a bidirectional switch across center nodes of the voltage doubler and corresponding modulation, the presented converter achieved almost ZVS at the turn-off instant; this trait significantly increases the power conversion efficiency even under high frequency operation. The inherent boost function of the current doubler, an additional boosting operation using a bidirectional switch, and double boosting of the voltage doubler enable the presented converter to achieve high voltage gain without having to use a transformer that has a high turns-ratio. Moreover, 180 $^\circ$ phase interleaving reduces the input current ripple to zero. The steady-state operation is analyzed comprehensively, and design considerations of the proposed converter are given. Finally, a prototype with input of 48-72 V, output of 380 V, and rated power of 1 kW is developed to validate the effectiveness and feasibility of the proposed converter.

中文翻译：

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用于燃料电池汽车的采用双向开关的高电压增益软开关转换器


传统的电流馈电谐振转换器在燃料电池电压的宽范围内存在高关断损耗的问题。为了缓解这个问题，我们提出了高电压增益电流馈电谐振转换器，该转换器可以在很宽的电压增益范围内实现几乎 ZVS 关断。通过在倍压器的中心节点上采用双向开关以及相应的调制，所提出的转换器在关断瞬间几乎实现了 ZVS；即使在高频操作下，这一特性也能显着提高功率转换效率。电流倍增器的固有升压功能、使用双向开关的附加升压操作以及倍压器的双重升压使得所提出的转换器能够实现高电压增益，而无需使用具有高匝数比的变压器。此外，180 $^\circ$ 相位交错可将输入电流纹波降至零。全面分析了稳态运行，并给出了所提出转换器的设计考虑因素。最后，开发了输入为48-72 V、输出为380 V、额定功率为1 kW的样机，以验证所提出的转换器的有效性和可行性。