The class-E converter with soft-switching has been widely used in high-frequency wireless power transfer (WPT) system. However, the high voltage stress on the switch limits its application. In this article, a compound voltage-clamped class-E converter, consisting of an auxiliary clamped circuit and class-E converter, is proposed in the WPT system to solve the issue. Through impedance analysis, SP (series–parallel) resonance network is employed for the proposed converter to reach high transfer efficiency. Meanwhile, based on the analysis of voltage stress on the switches and the boundary condition for zero-voltage-switch (ZVS) operation, the optimal operation region could be obtained, leading to a reduced voltage stress and switching loss together. Moreover, as the conduction duty-cycle becomes a controllable freedom in the proposed converter, the relationship between conduction duty cycle and output power is given out, which makes power transfer more flexible while maintaining ZVS operation synchronously. Finally, a prototype was built to verify the performance of the proposed topology, and the experiments agreed well with the calculation.

中文翻译：

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适用于 WPT 系统的具有 ZVS 和灵活功率传输的复合电压钳位 E 类转换器

具有软开关的 E 类转换器已广泛应用于高频无线电力传输 (WPT) 系统。然而，开关上的高压应力限制了它​​的应用。本文在WPT系统中提出了一种由辅助钳位电路和E类转换器组成的复合电压钳位E类转换器来解决该问题。通过阻抗分析，所提出的转换器采用 SP（串并联）谐振网络以达到高传输效率。同时，基于对开关上的电压应力和零电压开关（ZVS）工作边界条件的分析，可以获得最佳工作区域，从而降低电压应力和开关损耗。此外，由于导通占空比在所提出的转换器中成为可控的自由度，给出了导通占空比与输出功率的关系，在保持ZVS同步运行的同时，使功率传输更加灵活。最后，搭建了一个原型来验证所提出的拓扑结构的性能，实验结果与计算结果吻合良好。