本論文之研究內容為分析一主動箝位返馳式轉換器，以與傳統使用被動緩振電路之返馳式轉換器作比較。本論文所研製之主動箝位返馳式轉換器，主要是利用變壓器之漏電感與開關之寄生電容產生諧振，利用此一諧振特性達到開關之零電壓切換，藉此提升電路之效率及消除開關之電壓突波，並作電路之損耗分析。最後實作輸出規格為24V/8A/200W之電源供應器，實驗結果之波形與理論和模擬結果十分相符。

This thesis aims at the analysis of an active-clamping flyback converter. The comparisons between the active-clamping flyback converter and the conventional flyback converters adopting passive snubbers are made. The resonant tank of the active-clamping flyback converter consists of the leakage inductance of the transformer and the parasitic capacitance of the switch. The zero-voltage swtiching can be achieved by adequately design the circuit parameters. The conversion efficiency can thus be raised and the voltage spike on the switch can be reduced. Also the loss distribution is derived. An active-clamping flyback converter with an output rating of 24V/8A/200W is implemented in the lab. The experimental results are closely conformed to the theoretical analysis and the simulations.

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