本論文旨在將LLC串聯諧振電路的磁性元件進行整合研製和探討，並提出應用於通信電源的隔離式直流-直流轉換器。由於LLC諧振電路中包含許多磁性元件，即便提高電路的切換頻率縮小了磁性元件體積，多個分離式的磁性元件依然會佔據大量印刷電路板上的空間。因此本文對LLC串聯諧振電路中的磁性元件進行研究，在不改變一般商用鐵芯形狀的同時，利用磁通抵銷的方式將電路中的諧振電感與變壓器整合，進一步減少磁性元件的用量並縮小其體積。
論文利用磁路分析推導出其模型，並借助磁性模擬軟體ANSYS MAXWELL模擬出磁通抵銷的結果，利用抵銷的特性設計出基於LLC諧振式轉換器的整合式變壓器。最終完成一台工作頻率操作於125kHz，輸入電壓400V，輸出電壓55V，功率為1000W之電路，效率最高達94%的LLC諧振式轉換器電路。

This thesis focuses on the study and implementation of an integrated transformer for LLC-type series resonant converter that can be used on communication power. Since resonant converters contain many magnetic components, even if the switching frequency increased and the volume of magnetic components are reduced, multiple discrete components can still occupy a large amount of space on the printed circuit board. Therefore, this thesis studies on the transformer, without changing the shape of the core, the resonant inductor is integrated with the transformer by magnetic flux cancellation, which further reduces the number of magnetic components and its volume.
This paper derives the magnetic reluctance model and uses simulation software ANSYS MAXWELL to verify the characteristics of the integrated transformer based on resonant converter design. In the end, a flux cancellation transformer had been designed for a 125 kHz 400 V/55 V 1000 W LLC-type series resonant converter with 94% efficiency.

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