未來的電力系統中，由於多樣性再生能源的影響，存在電力供給不平衡與能量間歇性問題。為此，需要搭配具有雙向運作機制的儲能系統。本論文提出了一種應用於儲能系統的非隔離型雙向直流-直流轉換器。電池側使用兩組耦合電感實現高升壓、高降壓增益，並降低低壓側電流漣波。直流母線側則採用三階中性點箝位結構，以降低開關額定電壓的問題。此外，對磁性元件的設計進行了有限元素模擬分析，並提出了在磁芯上使用兩種磁性材料與不同氣隙分布的方析。最後，根據本文所提出的設計流程，研製出一低壓側60伏特、高壓側400伏特、額定功率300瓦、切換頻率為100千赫茲的轉換器，並對所提出之轉換器進行實作與驗證。實驗結果證明，所提出之雙向拓撲結構在輸出功率為300瓦的條件下，升壓模式最高效率為93.72 %，降壓模式最高效率為92.33 %。

In future power systems, the influence of diverse renewable energy sources will lead to issues of power supply imbalance and energy intermittency. To address these challenges, energy storage systems with bidirectional operation mechanisms are needed. This thesis proposes a non-isolated bidirectional DC-DC converter for energy storage systems. On the battery side, two sets of coupled inductors are used to achieve high voltage gain and reduce current ripple on the low-voltage side. The DC bus side employs a three-level neutral-point clamped structure to mitigate the problem of high switch voltage ratings. In addition, finite element simulation analysis was performed on the design of magnetic components, and an analysis of using two magnetic materials and different gap distributions on the magnetic core was proposed. Finally, following the design process outlined in this thesis, a converter with a low-voltage side of 60 V, a high-voltage side of 400 V, a rated power of 300 W, and a switching frequency of 100 kHz was developed and tested. Experimental results demonstrate the feasibility of the proposed bidirectional topology, achieving a maximum efficiency of 93.72 % in step-up mode and 92.33 % in step-down mode under the condition of a 300 W output power.

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