本論文首先介紹傳統半橋串聯諧振式轉換器(Half-Bridge Series Resonant Converter，HB-SRC)以及LLC形式半橋串聯諧振式轉換器(LLC HB-SRC)，並分析兩種形式之半橋串聯諧振轉換器在各個區間的動作原理以及等效模型推導。接著針對本論文所提出之雙變壓器雙諧振槽半橋串聯諧振轉換器進行電路動作分析及等效模型之推導，並使用Mathcad數學軟體模擬不同品質因數Q、K因子、特性阻抗Zo與變壓器圈數比(NP/NS)對電壓增益頻率響應之影響。
雙變壓器雙諧振槽半橋串聯諧振轉換器之優點為變壓器可均分輸出負載電流，減少變壓器銅損與輸出整流二極體之導通損，提高轉換器效率，分散變壓器體積，實現切換式電源供應器高功率密度之要求。本論文實作一台輸出電壓48 V、輸出瓦數800 W之雙變壓器雙諧振槽半橋串聯諧振轉換器，諧振頻率為74 kHz，並計算各個元件之損耗，比較實測結果和理論分析是否相符，最後提出未來可繼續研究之方向。

This thesis introduces a traditional half-bridge series resonant converter (HB-SRC) and an LLC-type half-bridge series resonant converter (LLC HB-SRC). Then the operating principles are analyzed and the equations of equivalent models are derived. Next, the operating principles and the equivalent circuit models of the proposed half-bridge SRC with dual transformers and resonant tanks are discussed in detail. The Mathcad software is applied to simulate the influences of the quality factor (Q), K factor, characteristics impedance (Zo), and the transformer turn-ratio (Np/Ns) on the frequency response of the voltage gain.
The advantages of the proposed converter is that the two transformers can share the output current to reduce the copper losses and the output diode conduction losses. By utilizing two transformers, the presented converter can achieve high efficiency and high power density. Experimental results are recorded for a prototype with an output voltage of 48 V, a rated output power of 800 W, and a resonant frequency of 74 kHz to verify the theoretical analysis. Future works for this research are also included.

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