本論文提出整合式雙變壓器主動箝位返馳式轉換器，其架構以兩組主動箝位返馳式轉換器所組成。此轉換器將雙變壓器整合成單一顆變壓器，因此可減少鐵芯損耗，也降低轉換器體積。就開關的元件應力而言，二次側可平均分擔輸出電流，降低輸出側二極體的傳導損耗，同時主開關與輔助開關皆有零電壓切換操作。
本文對整合式雙變壓器主動箝位返馳式轉換器之動作原理做分析與討論，配合軟體POWERSIM作模擬之驗證，實際完成一組輸入電壓為380Vdc，輸出電壓為19V，輸出電流為10A，操作頻率為100 kHz，滿載效率90%以上的電能轉換器。

關鍵字：主動箝位、返馳式轉換器、雙變壓器、零電壓切換、整合式雙變壓器。

Abstract
This thesis studies an active-clamping flyback converter using a integrated transformer. The proposed converter is composed of two active-clamping flyback converter. load current between two secondaries can be equally shared so that the rectifier diode conduction loss can be reduced. Otherwise, the main switch of any converter serves as auxiliary switch for the other one, so that only two switches are required and both can achieve zero-voltage-switching (ZVS) operation. The transformers of converter are integrated into one magnetic core, therefore, the volume and copper loss of transformer can be reduced. Detailed analysis and design of the integrated magnetic active-clamping flyback converter are described. POWERSIM simulation are shown for verification. Experimental results are discussed for a prototype converter with AC input voltage from 380 V, an output voltage of 19 V and an output current of 10 A, operating at a switching frequency of 100 kHz.

Keywords: Active clamping, flyback converter, integrated magnetic, zero-voltage-switching

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