主動箝位返馳式轉換器的優點有架構簡單、柔性切換特性等，然而，對於主動箝位返馳式轉換器拓樸而言，在輕載條件下，開關元件難以實現零電壓切換操作。本論文旨在研究於前級功率因數修正電路利用偵測負載電流的方法，在輕載條件下將前級PFC關閉以減少電路整體損耗、提高轉換效率。

An active-clamp flyback converter features simple structure and soft switching operations. However, the ZVS is difficult to achieve under light load condition. This thesis aims to study and implement an active-clamp flyback converter with a front-stage power factor corrector (PFC). Also a PFC turn-off function at light load is fulfilled by detecting the load current to improve the light-load conversion efficiency.

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