本文提出兩種具能量回收機制之降壓型電源轉換器，其中一種係利用隔離式的耦合電感，另一種係利用中間抽頭式的耦合電感。
一般應用在高電流變動的傳統降壓型電源轉換器（Buck converter），其受限於暫態響應，所以只能使用較小感值的電感，或是使用大容量的輸出電容。而使用較小感值的電感會導致較大的輸出電壓漣波，使用大容量的輸出電容會導致電路的成本及體積增加。
本論文所提出的電路是利用能量回收裝置來改善暫態響應及輸出電壓突波，使得電路不需要使用大容量的輸出電容，進而降低電路的成本與體積。最後，以實驗結果來驗證本文所提出電路具有快速的暫態響應、較小的輸出電壓漣波及較低的輸出電壓突波。

This thesis presents the buck converter with energy-recovery scheme by use of isolated coupled-inductor or center-tapped Coupled-inductor.
The buck converter is one of the most popular circuit topologies for the step-down application, especially, in the area of high load current applications with highly dynamic loads. In order to obtain fast transient response and less output-voltage spike, the small inductance value or a large output capacitor is used in buck converter. The small inductance results in a major output-voltage ripple. Moreover, a large capacitor causes increased cost and bulk for buck converter.
Therefore, this thesis proposes the buck converter with energy-recovery schemes to improve the full-to-low load transient response and reduce output-voltage spike. The configuration of proposed circuits is very simple and the capacity of the output capacitor can be minimized. Finally, the experimental results validate the advantages of the proposed circuits with fast transient response, less output-voltage ripple and low output-voltage spike.

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