電源供應器並聯使用可以提供電子設備高可靠度及大電流輸出的電源供應需求。但並聯電源供應器必須藉由均流技術才能確保負載電流均勻地分配至每一部電源供應器上。目前已經有相當多的並聯技術被發表，其中自動主僕均流技術之應用最廣泛的。自動主僕均流技術是屬於主動均流技術中的一種，主要是由外迴路控制法以及自動主僕均流匯流排所組成，具有低均流誤差率、容易實現模組化的設計等優點。
　　本文將直流電源供應器的並聯方法做一分類，評估每一種並聯方法之優劣，並使用自動主僕均流法實際製作由三部降壓式轉換器所組成之並聯系統，而此並聯系統的輸出為12V/30A(單一轉換器輸出為12V/10A)，實驗結果顯示本文所使用之並聯技術其均流誤差率均在5%之內，電壓調整率為1.21%，在負載變動期間亦能將負載電流平均分配，證明本文所使用並聯技術之可行性。

　　Paralleled use of power supply can provide electronic equipments with power demand of high reliability and high current output. However, paralleled DC-DC converters system requires current-sharing techniques to ensure that the load current can be equally distributed to everyone converter. At present, there are many paralleled techniques have been presented, and the applications of master-slave current-sharing control are most widely used among them. master-slave current-sharing control is one kind of active current-sharing technique, which is mainly composed of outer-loop control and master-slave current-sharing bus, and it has the advantages of low current-sharing error and easily to realize module design.
　　This thesis classifies the current-sharing techniques which are used in paralleled DC-DC converters system, and evaluates their merits and drawbacks for every kind of technique. Finally, a set of paralleled system with three 48V/12V 10A paralleled buck converters using master-slave current-sharing control is accomplished. From experimental result, the master-slave current-sharing control can provide an excellent voltage regulation within 1.21% and current-sharing error within 5% at full load condition. Experimental recordings verify the performance of this current-sharing control.

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