本論文提出應用於資料中心的隔離型直流-直流轉換器。電路架構採用能夠在全負載範圍達到一次側開關零電壓切換(ZVS)，二次側開關零電流切換(ZCS)的全橋LLC串聯諧振式轉換器，並使用寬能隙氮化鎵元件取代傳統矽元件，以降低功率開關的截止切換損耗。針對LLC諧振式轉換器穩壓的功能需求，需要足夠的諧振電感量提供足夠的增益作為調壓使用，因此利用外加諧振電感的方式。本論文採用整合型變壓器的結構，透過磁通抵銷與外側柱磁通分流的概念達到降低鐵芯損耗與提升功率密度的效果，並且利用四組矩陣變壓器與電感的方式，同時分散降低二次側大電流與電感磁動勢疊加造成交流損耗的上升，並利用鐵芯參數化的設計，在有限的電路布局面積下，綜合考量鐵芯損耗、銅線損耗與體積選擇出最佳的鐵芯設計點。利用ANSYS Maxwell磁性模擬軟體驗證平板變壓器的實際電路動作，包含電壓、電流轉換比與磁通密度分布是否符合設計理論。預計實現切換頻率操作於500 kHz、輸入電壓400 V、輸出電壓48 V、輸出功率為3 kW的全橋LLC串聯諧振式轉換器。

In this thesis, integrated matrix inductor and matrix transformer is proposed and implemented in an isolated DC-DC converter for 48V data-center bus architecture. The full-bridge LLC resonant converter is chosen as it can achieve soft-switching in the entire load range. In addition, the wide-bandgap gallium nitride device is used to further reduce turn-off switching loss. For regulated application, the resonant inductor should be large enough to achieve regulation capability. Therefore, it requires a con-trollable resonant inductor in series with a transformer. To achieve high power density and high efficiency, the magnetic integration of a resonant inductor and a transformer is proposed for this converter. To optimize magnetic components, the transformer with side leg for better flux distri-bution and flux cancellation can reduce core loss and achieve a thinner core profile. Additionally, a matrix inductor is designed to decrease ac winding loss. Within a limited circuit layout area, calculate the transform-er loss and volume for finding an optimal design point to meet the re-quirements of high efficiency and high power density. The magnetic sim-ulation software ANSYS Maxwell is used to verify the turns ratio and magnetic flux distribution conformed to the design theory. Finally, a LLC resonant converter was proposed to a switching frequency of 500 kHz, an input voltage of 400 V, an output voltage of 48 V and an output power of 3 kW.

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