近年來隨著環保意識抬頭，國際上大力推動再生能源，工業用中、高壓層級轉換器，在市場中佔比逐漸增加。以具有多種優點的串接型橋式轉換器為基礎，多年來各方研究提出了數種不同的串接型複合式轉換器。本文將針對由中性點箝位橋式轉換器與一般橋式轉換器組成的複合式架構進行研究。中性點箝位橋式轉換器可在增加輸出電壓階層數的同時，維持與一般橋式轉換器相同的開關跨壓，相較於全部由中性點箝位橋式轉換器組成的串接型轉換器，複合式架構中需控制中性點電位的模組較少，可降低整體控制複雜度。

　　然而串接型複合式轉換器亦有明顯的缺點，由於一般橋式轉換器與中性點箝位橋式轉換器切換方式不盡相同，切換時其輸出電壓經疊合後將一次跨越兩階層，使電壓諧波增大，影響整體電流品質，本篇論文將就此問題以調整載波的方式，降低輸出諧波。

　　另外，由於中性點箝位橋式轉換器的存在，需做中性點電位平衡控制，載波調整對其造成的影響，也將一併於文中討論。

In recent years, with people’s awareness of environmental protection enhancing, renewable energy has been promoted internationally. The market share of high and middle level converters for industry is gradually increasing. Based on the modular multilevel cascaded converter with many advantages, researchers have provided several hybrid cascaded converter. This thesis will focus on the hybrid structure composed of neutral point clamped H-bridge (NPC-bridge) and general H-bridge. NPC-bridge does not only increase the output voltage level but also maintain the stress voltage of switched as same as H-bridge. Comparing with the NPC-bridge modules of cascaded multilevel converter, modules which need neutral point potential(NPP) balancing control are less. So the complexity of hybrid cascade converter is lower.

　　However, there are some obvious disadvantage of hybrid cascade converter. Due to the difference between switch pattern of NPC-bridge and H-bridge, the overall output phase voltage crosses over two level with just one switching. It makes the harmonics of output voltage increase and affect the current quality. This thesis will improve this problem by modifying carrier wave. In addition, the necessary NPP balancing control for NPC-bridge will be influenced by it, the phenomenon will also be discussed.

目錄 III
圖目錄 VI
表目錄 XII
第 1 章 、緒論 1
1.1 研究背景與動機 1
1.2 論文內容概述 3
第 2 章 、文獻回顧 4
2.1 脈波寬度調變技術 4
2.1.1 相位配置脈波寬度調變(PDPWM) 4
2.1.2 相位移脈波寬度調變(PSPWM) 5
2.2 平均功率平衡控制 7
2.2.1 參數轉換之定義說明 (三相電壓、電流) 7
2.2.2 總體電壓平衡控制 9
2.2.3 簇電壓平衡控制 11
2.2.4 個別電壓平衡控制 14
2.3 中性點電位分析 16
2.3.1 單臂中性點箝位轉換器 16
2.3.2 中性點箝位橋式轉換器之向量平面 17
2.3.3 中性點箝位橋式轉換器對中性點電位之影響 18
2.4 中性點電位平衡策略 21
2.4.1 偏移注入平衡策略 21
2.4.2 雙極性調變平衡策略 24
第 3 章 、操作原理 31
3.1 平均功率平衡控制應用串接型複合式轉換器 31
3.2 以貝索近似式分析輸出電壓諧波 33
3.2.1 橋式轉換器 33
3.2.2 星型串接橋式轉換器 34
3.2.3 中性點箝位橋式轉換器 35
3.2.4 串接型複合式轉換器 36
3.3 藉載波調整消除低倍切頻諧波 39
3.3.1 以貝索近似式調整載波 39
3.3.2 串接型複合式轉換器調整後載波 41
3.3.3 串接多層複合式轉換器 43
3.3.4 串接多層複合式轉換器調整後載波 46
3.4 相同切換次數下輸出優劣 49
3.4.1 原始相位移脈波寬度調變 49
3.4.2 調整後相位移脈波寬度調變 50
3.4.3 相同切換次數下最低諧波頻率 50
3.5 中性點電位補償電量受載波調整影響 52
3.5.1 偏移量注入補償電量計算 52
3.5.2 雙極性調變補償電量計算 53
3.5.3 調整載波對補償電量影響 56
3.6 系統控制方塊圖 58
第 4 章 、機台實驗結果 60
4.1 簡介 60
4.2 平衡狀態操作 64
4.2.1 原始相位移脈波寬度調變 67
4.2.2 調整後相位移脈波寬度調變 69
4.2.3 頻譜分析 71
4.3 中性點電位平衡操作 73
4.3.1 偏移量注入 73
4.3.2 雙極性調變 83
第 5 章 、結論與未來展望 92
5.1 結論 92
5.2 未來展望 93
參考文獻 94

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