本論文提出「高效率二次側磁重置順向轉換器」之架構。其電路係利用一電容器與耦合電感於變壓器二次側來完成磁重置，且將磁化能量傳送至輸出端，藉以提昇轉換器效率。由變壓器二次側完成磁重置，可減少重置繞組所佔之繞線窗空間，達到有效利用繞線窗之目的。本論文中，首先逐一介紹順向式轉換器之發展，並討論各類順向式轉換器之優缺點，再對所提出之轉換器做動作原理敘述及穩態分析。最後實際實作一輸入電壓為200V、輸出電壓為48V、輸出功率為144W之「高效率二次側磁重置順向轉換器」，以驗證理論之可行性。

In this thesis, a high efficiency forward converter with secondary resetting magnetization is proposed. The capacitor and coupled inductor connect with the secondary winding of the transformer for the magnetizing reset. The efficiency of the proposed circuit is improved. Because magnetized energy is sent to the output load. In addition, the transformer winding is reduced due to the discharged magnetizing current from secondary winding. Therefore, the efficiency of winding area is improved. At first, the related topologies of forward converter are reviewed and the characteristics of these topologies are expressed. Secondly, the operating principles of the proposed converter are presented, and the steady-state analysis is also explained in this thesis. Finally, a laboratory prototype with 200V input and 48V/144W output is implemented to verify the theoretical analysis.

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