電池儲存系統（Battery Storage System, BSS）為現代電力應用中的關鍵系統之一，其應用包含：可再生能源系統和電動汽車等。然而，在電池儲存系統中，不同電池間常會存在充電不平衡的現象，這會降低系統之操作效率、可靠性和安全性。因此，許多文獻提出了將電池能量平衡的技術，而其中的切換式電容（Switched Capacitor, SC）平衡器因具有成本低、體積小和容易實現等優點，而受到許多關注。
　　本論文針對七種切換式電容平衡器進行分析，包含：傳統型切換式電容平衡器、雙層切換式電容平衡器、模組化切換式電容平衡器、加入開關之切換式電容平衡器、加入電容之切換式電容平衡器、串並聯切換式電容平衡器和單切換式電容平衡器。首先，根據平衡器在充、放電時之動作，推導及建立數學模型，並提出評估各平衡器性能之方法；並以MATLAB數學模型模擬平衡時間，進行統計與分析，比較各切換式電容平衡器架構之性能，由模擬結果得知，當串聯電池數增加至八顆以上時，串並聯切換式電容平衡電路之平衡時間最短，雙層、模組化、鏈狀切換式電容平衡電路之平衡時間相近，而傳統行切換式電容平衡電路之平衡時間最長；最後，依照所選擇之七種平衡器拓撲，針對其電路設計複雜度、平衡速度和實際實現難易度做總結，可讓使用者可在不同狀態與需求下，有效選擇適合的架構。

　　Battery storage system (BSS) is one of the key components in a number of modern power applications such as renewable energy systems and electric vehicles. However, charge imbalance among different batteries is very common in a BSS, which may impair the power efficiency, reliability and safety. Hence, various battery equalization methods have been proposed in the literatures. Among those battery equalizing techniques, the switched capacitor (SC) equalizer attracts many attentions due to its low cost, small size, and easy control.
　　In this thesis, seven types of SC-based equalizer: conventional SC, double-tiered SC, modularized SC, chain structure SC type I, chain structure SC type II, series-parallel SC and single SC are studies. Mathematical models that describe the charging-discharging behaviors are first derived. Next, analytical methods are also developed to evaluate the performance. In addition, statistical analysis based on MATLAB simulation is also carried out to compare the performance of the seven SC-based equalization structures considered. Finally, summary of circuit design complexity, balancing speed and practical implementations of the seven compared topologies will be provided.

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