本文提出雙變壓器主動箝位反逆型SEPIC轉換器，其架構以主動箝位反逆型SEPIC轉換器為基礎，利用共生之方式將兩組單晶電源轉換器組合。此創新架構之優點為變壓器可均分負載電流，以分散變壓器體積，並易於實現電源供應器低高度設計與高功率密度之要求。另外轉換器只需兩個切換開關，因而可降低轉換器成本，並且兩組切換開關皆操作於零電壓切換，可提高轉換器效率。兩個切換開關的責任週期為互補性，與一般主動箝位架構相同，因此輸出電壓或負載的調整範圍不受影響。

This thesis presents a two-transformer active-clamping zero voltage-switching (ZVS) inverse-SEPIC converter. The proposed topology is mainly composed of two active-clamping counterparts. By utilizing two separate transformers, the proposed converter allows a low-profile design to be implemented with the merits of the conventional single-transformer topology. Only two switches are required. The circuit complexity and cost are thus reduced. The transformer leakage inductance or an external resonant inductor is employed to achieve ZVS during the dead times, and therefore the converter efficiency is improved. As the conventional active-clamping converter, the duty cycles of the two switches for the proposed two-transformer topology are complementary. Thus the ranges of the output voltage under load variation are not affected.

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