This article proposes a highly efficient quasi-single-stage ac–dc converter that incorporates a bidirectional switch at the secondary side of the circuit. Its attractiveness is that the proposed ac–dc converter achieves almost ZVS turn-off at high instantaneous power and low-voltage turn-off at low instantaneous power. Moreover, the secondary-side switching reduces the loss at the main switch, and thereby more than offsets the losses that occur at the main switch and the clamp switch in a conventional ac–dc converter. An additional benefit of this converter is that the voltages across the primary-side capacitors and secondary-side capacitors are well balanced because the duty cycle at the primary-side switch is fixed at 0.5. Experimental results show that the proposed ac–dc converter is effective and more efficient than a conventional solution.

中文翻译：

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采用双向开关的高效准单级 AC-DC 转换器

本文提出了一种高效准单级 AC-DC 转换器，该转换器在电路的次级侧集成了一个双向开关。其吸引力在于，所提出的交流-直流转换器在高瞬时功率下实现了几乎 ZVS 关断，在低瞬时功率下实现了低压关断。此外，次级侧开关降低了主开关的损耗，从而大大抵消了传统交流-直流转换器中主开关和钳位开关处的损耗。该转换器的另一个好处是初级侧电容器和次级侧电容器两端的电压非常平衡，因为初级侧开关的占空比固定为 0.5。实验结果表明，所提出的交流-直流转换器比传统解决方案有效且效率更高。