本篇論文提出一種複合式模組多階層串接型轉換器架構，利用單相橋式轉換器串接三相三階中性點箝位轉換器組成之複合式架構進行研究。與一般星型串接橋式轉換器相比，在最後一層將橋式轉換器改為三相三階中性點箝位轉換器。此外，在維持相同的輸出電壓階層數時，減少了電路上電容及直流鏈電壓感測器之數量，再加上對於三相三階中性點箝位轉換器之直流鏈電壓在沒有兩倍頻漣波電壓的影響下，其電容容值及體積能因此減小，提供一種模組多階層串接型轉換器的選擇。
然而，在此複合式串接型轉換器下，由於橋式轉換器與三相三階中性點箝位轉換器切換方式不盡相同，切換時造成其輸出電壓經疊合後將一次跨越超過一階層，使得輸出電壓諧波增大，進而影響整體電流品質。因此，本論文將針對此問題提出改善方式，首先介紹本文架構之直流鏈電壓平衡控制，再利用雙重傅立葉積分分析其輸出電壓，並藉由調整其載波的方式，改善其輸出電壓諧波分布，進一步提升其輸出電流品質，最後在相同切換次數下比較傳統型相位移脈波寬度調變和調整後相位移脈波寬度調變的表現。本文以實驗機台的結果驗證此篇論文所提出之方法的正確性。






關鍵字: 模組多階層串接型轉換器、複合式串接型轉換器、直流鏈電壓平衡控制、相位移脈波寬度調變

This thesis presents a hybrid topology of modular multilevel cascaded converter, composed of the single-phase H-bridge converter and the three-phase three-level neutral point clamped (NPC) converter. Compared with the conventional star-connected cascaded H-bridge converter, this circuit substituted the last layer of single-phase H-bridge converters with the three-phase three-level neutral point clamped converter. Not only it can maintain the same number of output voltage level, but also reduce the number of capacitor and DC bus voltage sensor in the circuit. Furthermore, the value of capacitor and its volume can be lowered because the DC bus voltage of the three-phase three-level NPC converter has no effect of the double-frequency ripple voltage. It provides a choice of the modular multilevel cascade converter.
However, as a result of the difference between switch pattern of H-bridge converter and three-level NPC converter under the hybrid cascaded converter, the overall output voltage cross over more than one level. It will result in the harmonics of the output voltage increase and affect the output current quality. Therefore, this thesis will adjust the carrier wave for this problem. The harmonic distribution of the output voltage and the output current quality can be improved. Compared to conventional phase shift pulse width modulation (PSPWM), better performance of modified PSPWM can be obtained under the same switching times. The proposed control method is validated by experimental results.

Keywords: Modular multilevel cascaded converter、Hybrid cascaded converter、Phase shift pulse width modulation

摘要 I
Abstract II
誌謝 III
目錄 IV
圖目錄 VII
表目錄 XI
第一章、緒論 1
1.1 研究背景與動機 1
1.2 論文內容概述 3
第二章、文獻回顧 4
2.1 簡介 4
2.2 脈波寬度調變技術 4
2.2.1 三階中性點箝位轉換器之相位配置脈波寬度調變(PDPWM) 4
2.2.2 三階空間向量調變法 5
2.2.3 多階層轉換器之相位移脈波寬度調變(PSPWM) 9
2.3 空白時間補償器 10
2.3.1 空白時間(Dead-time)產生 10
2.3.2 空白時間補償器(Dead-time compensator)方法 12
2.4 平均功率潮流分析 17
2.4.1 參數轉換之定義說明 (三相電壓、電流 ) 18
2.4.2平均功率定義及分析 (總體功率、簇功率) 20
第三章、操作原理 27
3.1 簡介 27
3.2 電壓平衡控制 27
3.2.1 整體電壓平衡控制與虛功功率控制 28
3.2.2 混合式電壓控制 28
3.2.3 簇電壓平衡控制 29
3.2.4個別電壓平衡控制 31
3.3 以貝索近似式分析輸出電壓諧波 32
3.3.1 橋式轉換器 32
3.3.2 單相串接橋式轉換器 33
3.3.3 中性點箝位轉換器之單臂 34
3.3.4 複合式串接型轉換器 35
3.4 藉載波調整分配其諧波分布 38
3.4.1 以貝索近似式調整個別載波 38
3.4.2 複合式串接型轉換器調整後之載波 40
3.5 相同切換次數下之輸出比較 41
3.5.1 傳統型相位移脈波寬度調變 42
3.5.2 調整後相位移脈波寬度調變 42
3.5.3 相同切換次數下之輸出電壓諧波分布 43
3.6 系統控制方塊圖 44
第四章、機台實驗結果 46
4.1 簡介 46
4.2 穩態下之平衡操作 49
4.2.1 傳統型相位移脈波寬度調變 49
4.2.2 傳統型調變技術之零序電壓注入作三階空間向量調變法 53
4.2.3 調整後相位移脈波寬度調變 57
4.2.4 調整後調變技術之零序電壓注入作三階空間向量調變法 61
4.3 頻譜分析 65
第五章、結論與未來展望 71
5.1 結論 71
5.2 未來展望 72
參考文獻 73

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