基於現有的耦合電感和切換電容拓撲上，本論文提出一種具有零電壓零電流切換的新穎高升壓轉換器。根據眾多再生能源的特性，此類轉換器通常需要較高的升壓比、效率和較大的容量。故交錯並聯和主動箝位技術被引進在本文所提出的轉換器中。
穩態工作時，轉換器耦合電感器的漏感會與兩顆切換電容器諧振。在不同的諧振頻率下，零電壓導通和零電流截止會分別在部分功率開關和整流二極體上實現。故開關損耗和反向恢復問題會有所減輕，進而提高了轉換器的效率。由於引進了交錯並聯機制和更多的開關數量，每一顆耦合電感器的匝數比可以大大减少，且一次側的電流應力也有所降低，故轉換器整體容量可以顯著提高。
在實驗之前，包含升壓比在內的電路穩態特性在本文中均進行了詳細的推導，並和現有的電路進行了比較。另外，區分軟切換模式的邊界圖也在文中繪出並通過軟體模擬進行了驗證。最後，基於控制器TMDSDOCK28035，具有24 V輸入電壓、400 V輸出電壓、800 W輸出功率的電路原型也製作出用以驗證所提轉換器之可行性。

In this thesis, a novel high step-up DC-DC converter with ZVZCS is proposed based on several existing coupled-inductor and switching-capacitor topologies. According to the characteristics of renewable energy sources, these kinds of converters are usually required to have a high conversion ratio, high efficiency and large power capacity. Therefore, the interleaving and active-clamp techniques are introduced.
During steady-state operating modes of the proposed converter, the leakage inductor of the coupled inductors resonates with two switching capacitors. Under different resonant frequencies, ZVS turn-on and ZCS turn-off can be realized for certain power switches and rectifying diodes, respectively. Therefore, the switching loss and reverse recovery problems are alleviated, which improves the efficiency of the converter. Thanks to the interleaving mechanism and more switches, the turn ratio of each coupled inductor can be reduced dramatically, along with less current stress in the primary-side winding. Therefore, the power capacity can be improved significantly.
Before experiment, steady-state performance including the voltage conversion ratio is derived and compared with existing ones. In addition, the mode boundary map for distinguishing soft-switching modes is depicted and verified by the software simulation. Finally, a prototype with 24 V input voltage, 400 V output voltage and 800 W output power using controller TMDSDOCK28035 is implemented in the laboratory to verify the feasibility of the proposed converter.

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