近年來，再生能源被國際所推動，中、高壓層級轉換器也逐漸被廣泛應用，其中包含了多種模組多階層串接型轉換器(Modular Multilevel Cascaded Converter, MMCC)及衍生之混合式串接型轉換器(Hybrid Cascaded Converter, HCC)。
本論文將針對由橋式轉換器及三相二階轉換器組成之混合式架構進行研究。和星型串接橋式轉換器(Single-Star Bridge Cell, SSBC)相比，在相同的轉換器串接層數下，三相二階轉換器可減少六組開關、兩個直流鏈電容以及兩個直流鏈電壓感測器。此外，由於三相二階轉換器的直流鏈電壓上並無兩倍頻漣波，對於電容容值的需求也可以降低。
但是，這種架構的混合式串接型轉換器若是應用一般的相位移脈波寬度調變(Phase-Shifted Pulse Width Modulation, PSPWM)，會得到很大的輸出電壓諧波，進一步影響輸出電流的品質。對此，本論文將藉由雙重傅立葉積分分析(Double Fourier Integral Analysis, DFIA)計算輸出電壓頻譜分布，提出一個新的脈波寬度調變策略，使其有最好的諧波消除，並能有效的降低輸出電流的電流總諧波失真，提升混合式串接型轉換器的輸出電流品質。同時，在相同切換次數下，以磁鍊漣波分析(Flux ripple analysis)與星型串接橋式轉換器比較其輸出表現。
最後在實驗平台上分別實作混合式串接型轉換器及星型串接橋式轉換器的架構，透過實驗結果驗證提出的脈波寬度調變策略及理論分析之正確性。

In recent years, renewable energy has been promoted internationally. Middle and high level converters are also applied gradually, including many types of Modular Multilevel Cascaded Converters (MMCC) and Hybrid Cascaded Converters (HCC).
This thesis will research on the structure which is composed of H-bridge converters and a three-phase two-level converter. Compared to Single-Star Bridge Cell (SSBC), three-phase two-level converter needs less switches and DC bus voltage sensors under the same cascaded number. Moreover, because there is no second-order harmonic ripple in the DC bus voltage of three-phase two-level converter, its demand on the capacitor value can be reduced.
However, if conventional Phase-Shifted Pulse Width Modulation (PSPWM) is applied under this type of structure of HCC, the harmonic voltage will be huge, and thus affects the quality of output currents. Therefore, this thesis will calculate the output voltage spectrum by Double Fourier Integral Analysis (DFIA), and propose a new Pulse Width Modulation (PWM) technique to obtain the optimized harmonic cancellation, effectively decrease the Total Harmonic Distortion (THD) of output currents, and improve the quality of output currents of HCC. Meanwhile, compare it with SSBC through flux ripple analysis based on the same switching number.
Finally, the structure of HCC and SSBC will be operated on the testbench respectively. Meanwhile, verify the proposed PWM technique and the theoretical analysis results through experimental results.

摘要..............................................................I
Abstract........................................................II
致謝............................................................III
目錄.............................................................IV
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 論文內容與概述.................................................3
第二章、文獻回顧...................................................4
2.1 簡介..........................................................4
2.2 相位移脈波寬度調變.............................................4
2.3 空白時間補償器.................................................6
2.3.1 空白時間之實現...............................................6
2.3.2 空白時間補償器之實現.........................................7
2.4 平均功率潮流分析...............................................9
2.4.1 使用參數之定義(三相電壓及電流)...............................10
2.4.2 整體電壓平衡控制............................................12
2.4.3 混合式電壓平衡控制..........................................15
2.4.4 簇電壓平衡控制..............................................16
2.4.5 個別平衡控制...............................................23
第三章、操作原理..................................................24
3.1 簡介.........................................................24
3.2 輸出電壓之雙重傅立葉積分分析...................................24
3.2.1 橋式轉換器之輸出電壓諧波分析.................................24
3.2.2 星型串接橋式轉換器之單相輸出電壓諧波分布......................26
3.2.3 混合式串接型轉換器之單相輸出電壓諧波分布......................27
3.3 臂移脈波寬度調變策略..........................................29
3.3.1 臂移脈波寬度調變之載波位移規則...............................29
3.3.2 臂移脈波寬度調變之命令更新...................................31
3.4 磁鍊漣波分析.................................................33
3.4.1 磁鍊之計算.................................................33
3.4.2 不同振幅調變比率之磁鍊計算...................................36
3.4.3 開迴路模擬驗證磁鍊連波分析...................................38
3.5 系統控制方塊圖................................................41
第四章、機台實驗結果..............................................43
4.1 簡介.........................................................43
4.2 靜態虛功補償器於平衡下之穩態操作...............................46
4.2.1 三層星型串接橋式轉換器應用相位移脈波寬度調變..................46
4.2.2 三層混合式串接型轉換器應用相位移脈波寬度調變..................49
4.2.3 三層混合式串接型轉換器應用臂移脈波寬度調變....................52
4.3 靜態虛功補償器於暫態時之操作...................................55
4.3.1 三層混合式串接型轉換器變換額定虛功命令........................55
4.3.2 三層混合式串接型轉換器操作於電壓驟降..........................58
4.4 頻譜分析.....................................................61
第五章、結論與未來展望............................................66
5.1 結論.........................................................66
5.2 未來展望.....................................................67
參考文獻.........................................................68

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