本論文主旨為固態變壓器之探討與研製。首先討論傳統交流-交流轉換器的基本動作原理及優缺點，並針對架構本身漏感大小對電路架構的電壓增益產生的影響加以討論，為了維持良好的電壓增益，本論文提出全橋交流-交流串聯諧振式轉換器，將其電路操作於諧振頻率點，藉此改善輸出電壓受影響的程度，並分析其電路動作原理及狀態分析。
論文中將詳盡介紹電路動作模式以及分析各個動作區間之等效電路，並推導整體電路增益等校模型，最後以規格輸出功率 1 kW、輸入電壓110 Vrms、輸出電壓110 Vrms之單相交流-交流全橋串聯諧振式轉換器實現，接續說明電路硬體設計、諧振槽設計及變壓器設計，將實測結果和理論及模擬相互印證，實測結果不僅顯現電路符合其動作狀態，並且全域效率轉換都達90％以上，最後並研擬未來研究方向。

This thesis focuses on the study and development of solid-state transformers. First, the basics of AC-AC converters is discussed. Specifically, the effect of leakage inductance on output voltage is analyzed. Hence in this thesis, a AC-AC full-bridge series resonant converter is applied to maintain output voltage. The circuit is operated close to the series resonant frequency to improve the output voltage regulation. The state analysis and basic operating principles of the proposed converter are discussed in detail.
Finally, a prototype AC-AC full-bridge series resonant converter with an input/output voltage of 110 Vrms, output power 1 kW is implement and tested. The efficiency can be higher than 94.04% at full load condition. The theoretical analysis is positively agreed with the experimental results.

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