本論文主要研製三相隔離式直流-直流升壓轉換器，用於低壓輸入高壓輸出的應用場合。所研製的轉換器包含由三個半橋所組成的三臂切換開關、三個隔離變壓器、三相整流二極體與輸出電感電容所組成的濾波電路。三個變壓器是以Δ-Y接的方式連結，使一次側並聯、二次側串聯。功率開關的驅動方式分別使用了非對稱與對稱驅動的控制策略。此電路架構使低壓大電流的一次側有很好的分流效果，而在升壓轉換中則有高電壓轉換比例的優點。與一般的電流饋入全橋轉換器相較，本文所研製的電路拓樸會有更高的轉換效率。
本論文已完成一台輸出功率2 kW的實體電路，輸入電壓範圍從37 V到57 V，輸出電壓為400 V。並以數位訊號處理器TMS320F2808來實現數位控制轉換器的目的。在不同的輸入電壓與不同負載下，非對稱驅動所得效率為87 % ~ 92.1 %；對稱驅動所得效率為82.5 % ~ 93.3 %。

This thesis aims to study a three-phase isolated DC-DC boost converter for low voltage input/ high voltage output applications. The studied converter consists of three half-bridge switch legs, three isolated transformers, a three-phase diode rectifier and an output LC filter. The three isolated transformers are configured in Δ-Y connection with parallel primary and series secondary terminations. Asymmetrical and symmetrical control schemes are respectively used for driving the power switches. Good current sharing performance can be achieved for low voltage/ high current primary side. The studied step-up converter has the advantage of high voltage-transfer-ratio. Compared with the conventional current-fed full-bridge converter, the studied topology presents high conversion efficiency.
In this thesis, a laboratory prototype with 2 kW output power has been built and tested. The input voltage is from 37 V to 57 V and the output voltage is 400 V. A DSP chip TMS320F2808 is used to realize the digital controller of the prototype converter. With an asymmetrical driving scheme, the measured efficiency is from 87% to 92.1% under input voltage and load variations. With a symmetrical driving scheme, the measured efficiency is from 82.5% to 93.3%.

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