本文提出雙變壓器主動箝位零電壓切換順向式與返馳式轉換器，其架構以單晶(單開關)主動箝位零電壓切換順向式轉換器或主動箝位零電壓切換返馳式轉換器為基礎，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。另外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 paper presents a two-transformer active-clamping zero-voltage-switching (ZVS) forward converter and a two-transformer active-clamping zero-voltage-switching flyback converter. Each 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 readily implemented while retaining the merits of a conventional single-transformer topology. Only two switches are required. The circuit complexity and cost are thus reduced. The leakage inductance of the transformer or an additional resonant inductance is employed to achieve ZVS during the dead times, and therefore the converter efficiency are improved. Like 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 and the load variation are not affected.

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