使用高壓開關單元（High-voltage Switch Cell）取代單開關電力轉換器之主開關，可以推導獲得多個雙開關電力轉換器電路架構。由於開關元件電壓應力得以降低，因此可以使用較低電壓規格之MOSFET，而有較低的等效導通電阻RDS(on)，降低導通損失，轉換效率可以獲得改善。本文提出其中之三個不同去磁機制雙開關型順向式轉換器，分別為第三繞組，RCD箝位和主動箝位。除了電路工作原理之介紹，並以輸入範圍40-60V和5V/16A輸出電路規格，共同以開關頻率150 kHz，進行實驗，量測電壓及電流波形，並比較其單、雙開關電路架構的效率。

A high-voltage switch cell is proposed to replace the active switch in the single-switch power converters and two-switch topologies can be derived. Among them, three two-switch forward converters with various reset schemes, two-switch forward converter with tertiary winding, two-switch forward converter with RCD clamped and two-switch forward converter with active clamped are presented in this thesis. Because the voltage stress can be alleviated, low voltage rating MOSFET accompanied with lower equivalent RDS(on) results in the reduction of the conduction losses. Therefore, the efficiency improvement can be obtained.
To demonstrate its feasibility, the operation principles of three two-switch forward topologies with various reset schemes as well as the experimental results with 150 kHz, 40-60V input and 5V/16A output are described in the thesis.

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