本文主要目的在於針對微直流電網與其所並聯之電池儲能系統之間的介面電路，提出一新型雙向電力轉換器，以作為電池儲能與釋能調節微直流電網系統之電力品質之應用。基本上本論文主要貢獻可概述如下幾點。首先，本論文提出一新型雙向直流轉換器電路，不僅具有電器隔離特性，並可作為儲能充電器與反向釋能至微電網系統，而其特色為高壓側模組具有嵌入式之功能，即可配合電池不同電壓層級之需求選用N倍壓模組，N≧2，且自2倍壓模組開始，每增加一倍電壓，僅需增加一個主動開關與一個電容器；至於低壓側則採用雙向倍流器架構，可減少變壓器電流及採用同步整流控制而大大減少耗損。其次，本論文更進一步採用二組二倍壓轉換器以高壓側串聯低壓側並聯之架構，提升至更大容量，同時作更深入之理論分析與直流模型與小信號模型推導，以利配合併聯微直流電網系統之調節控制。最後，根據本文理論分析之結果，實際製作壹台規格為高壓側電壓400V、低壓側電壓48V與額定功率為1kW之雛型電路，以驗證所提新型轉換器之可行性。實測結果顯示該轉換器於降壓模式下之最高效率可達94.1%，升壓模式下之最高效率可達94.4%。

The main purpose of this thesis is focused on the study of an interface between a battery energy storage system and a paralleled DC microgrid with a view to develop to a novel bidirectional dc converter for regulating the DC microgrid. Basically, the major contributions of this thesis can be summarized as follows. First, a new bidirectional dc converter structure is proposed. This new topology can not only achieve electrical isolation and bidirectional power flow capability, but also can be embedded with a voltage multiplier module in high voltage side to obtain N times voltage step up/down, where N is a positive integer greater than is equal to two. Also, starting from N≧2, only one more active switch and one more capacitor are required for increasing/decreasing one more voltage level step up/down. Secondly, to demonstrate the way of increasing the power handling capability, two sets of the proposed bidirectional basic converter are interconnected together such that the high voltage sides are in series and the low voltage sides are in parallel. Meanwhile, the corresponding DC and AC models are derived for feedback controller design. Finally, a 1kW prototype with 400V high side voltage and 48V low side voltage have been constructed to verify the feasibility of the proposed converter. It can be seen that maximum efficiencies are 94.1% and 94.4% for step down and step up operation modes respectively.

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