因應再生能源取之不盡，微型換流器可望成為未來應用趨勢之一。相較一般換流器，微型換流器擁有體積小、安裝簡易、成本低等優點，更適用於一般住宅。因此本篇論文主要研製之交錯式無損耗L-C-D緩振順向-返馳式轉換器，為微型換流器之前級直流/直流轉換器。由於輸入端一般為太陽能電池、燃料電池等，故此轉換器做低壓輸入、高壓輸出之應用。
本文先分析傳統返馳式轉換器以及各式被動緩振器，再者介紹傳統順向式轉換器的工作原理，並比較返馳式及順向式兩電路架構的優缺點，取兩者之優點衍生出變型順向-返馳式轉換器。其次分析順向-返馳式轉換器的工作原理、探討交錯式順向-返馳式轉換器之優點，進而設計電路元件以250 W實現原型電路。規格為輸入電壓37 V、輸出電壓400 V，實現具無損耗L-C-D緩振器之交錯式順向-返馳式轉換器。

Due to its small size, a micro-inverter is especially suitable for household power systems. With the inexhaustible regenerative energies, micro-inverters are expected to find wide applications in the future. This thesis focuses on the study and implementation of interleaved forward-flyback converters with non-dissipative L-C-D snubbers. The studied converter serves as the front-stage DC-DC converter of a micro-inverter system. Generally the inputs of the converter are solar cells and fuel cells, therefore, it is suitable for low input voltage and high output voltage applications.
First, the operations of a conventional flyback converter and various kinds of non-dissipative snubbers are analyzed. Then the working principles of a conventional forward converter are described. The pros and cons of these two topologies are discussed and compared. Featuring the advantages of the above two topologies, a forward-flyback converter is derived. The operations of the presented forward-flyback converter are introduced. Also the advantages of interleaved topologies are listed. Finally, a 250-W laboratory prototype with a 37-V input and a 400-V output is designed and realized.

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