近來在中電壓等級(2.3、3.3、4.16和6.9千伏)功率控制的應用領域中，多階逆變器扮演著重要的角色，而在此電壓層級中以三階層中性點箝位逆變器最為廣泛的被使用。本論文依據電路級解偶合法則分析定義動作區間內的調變規則，假設中性點電壓平衡並以零相序電壓注入的觀點切入，提出一應用於三階層中性點箝位逆變器且具有低電壓諧波失真與低切換損失的非連續載波脈波寬度調變機制，促使調變機制更易於實現，並且加入中性點電壓平衡控制。最後以實驗室等級之電路原型實現，驗證本論文提出之非連續脈波寬度調變機制的可行性。

Multilevel inverter technology has emerged recently as a very important alternative in the area of medium-voltage (2.3, 3.3, 4.16, and 6.9 kv) energy control. The three level neutral-point-clamped (NPC) inverter is the most extensively applied multilevel inverter topology in this area. Based on the circuit-level decoupling principle, the implementation of modulation scheme can be significantly simplified in every defined operating section through deriving the zero-sequence voltage with assuming balanced neutral-point voltage. This thesis presents a carrier-based discontinuous pulse width modulation (DPWM) strategy with zero-sequence voltage injection and neutral-point voltage balancing control for the three level NPC inverter. The proposed DPWM strategy not only takes advantage of low voltage harmonic distortion, but also reduces the switching loss of the inverter. Finally, the viability and performance of the proposed DPWM strategy are verified in the laboratory prototype.

摘要　　iii
Abstract　　iv
目錄　　v
圖目錄　　vii
表目錄　　x
第一章 緒論 1
1.1 研究背景與動機 1
1.2 論文大綱 3
第二章 文獻回顧 4
2.1 三階層中性點箝位逆變器 4
2.2 逆變器之調變機制 6
2.2.1非連續調變機制 7
2.3 基於電路級解耦合法則之調變機制 9
2.3.1區間I、III、V之調變機制 11
2.3.2區間II、IV、VI之調變機制 12
2.4 中性點電壓控制 16
2.5 總結 18
第三章 逆變器調變原理 19
3.1 非連續脈波寬度調變機制 19
3.1.1 同相階層式脈波寬度調變 22
3.1.2 零相序電壓注入法 24
3.2 中性點電壓平衡控制 29
3.3 總結 32
第四章 實驗結果與分析 33
4.1 實驗設計 33
4.2 理論調變機制之實驗波形 35
4.2.1本論文提出之非連續調變機制的諧波分析 43
4.2.2各條變機制之諧波失真比較 46
4.2.3各調變機制之效率比較 47
4.3 直流鏈上、下電容電壓平衡控制 50
4.4 中性點電壓平衡能力之探討 53
4.5 總結 56
第五章 結論與未來研究方向 57
5.1 結論 57
5.2 未來研究方向 57
參考資料 58

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