近年來，隨著環境保護意識的興起，各國政府開始發展再生能源，因此太陽能光伏系統開始應用在中、高壓層級之電力系統及工業應用上。透過模組化多階層串聯轉換器可解決傳統橋式轉換器中單一開關需承受高電壓應力的問題，因此被廣泛使用於中、高壓系統上。串接型轉換器是透過模組之間相互連接，隨著串接數的增加，將提升數位訊號處理器的迴授訊號數量及訊號傳輸複雜度，以上問題將導致串聯模組數無法輕易擴張。

本篇論文將於模組化多階層星型串聯橋氏轉換器之電路架構下，根據全橋轉換器開關的切換情形，來建立出一個全橋轉換器的平均切換模型，並將此平均切換模型應用於模組化之多階層星形串聯橋氏轉換器架構上，再經由靜止框轉換(Clarke transformation)及同步框轉換(Park transformation)後，可得到模組化多階層星型串聯橋氏轉換器在同步框下之簡易平均模型。並建立出MMCC-SSBC基於總體電壓平衡控制之簡化模型，經由簡化模型求出直流鏈電壓命令與實際直流鏈電壓的轉移函數，最後透過根軌跡圖上的資訊來得知直流鏈電壓動態情形。本文以實驗平台的結果驗證此篇論文所提出之簡化模型的正確性。

In recent years, with the awareness of environmental protection, governments begin to development of renewable energy. Therefore, the photovoltaic(PV) systems begin to be applied to power system and industrial application at medium and high voltage levels. The modular multilevel cascaded converter can solve the problems of high voltage stress of single switch in traditional bridge converter. Therefore, it is widely used in medium and high voltage systems. The cascaded converter are composed by serial cell modules. As the cascaded numbers increase, the number of feedback signals and signal transmission complexity of digital signal processor will also increase. As explained earlier, the number of serial modules can not be simply expanded.
This thesis is based on a modular multilevel star-connected H-bridge converter. According to switching states of H-bridge converter switch, it can establish an average switching model of H-bridge converter. The average switching model can be applied to MMCC-SSBC, and the simplified average model of MMCC-SSBC under synchronous frame can be obtained after Clarke transformation and Park transformation. Establishing the simplified model of MMCC-SSBC bases on overall voltage balancing control. By the simplified model, the transfer function of dc link voltage command and actual dc link voltage can be obtained. Finally, through the information of root locus, the dc link voltage dynamic condition can be obtained. The proposed simplified model is verified by experimental results.

摘要......................................................I
Abstract..................................................II
誌謝......................................................III
目錄......................................................IV
圖目錄....................................................VII
表目錄....................................................XII
第一章、緒論...............................................1
1.1 研究背景與動機......................................1
1.2 論文內容概述........................................4
第二章、文獻回顧...........................................5
2.1 簡介...............................................5
2.2 相位移之單極性正弦脈波寬度調變.......................5
2.3 平均功率潮流分析(Average Power Flow Analysis).......7
2.3.1 參數轉換之定義說明 (三相電壓、三相電流).............8
2.3.2 總體電壓平衡控制與虛功控制.........................12
2.3.3 簇電壓平衡控制....................................15
2.3.4 個別電壓平衡控制..................................21
第三章、實驗平台介紹及操作原理..............................23
3.1 簡介...............................................23
3.2 系統架構介紹........................................23
3.3 模組板電路介紹......................................26
3.3.1 模組板功能說明....................................26
3.3.2 反馳式轉換器(Flyback)模組供電設計..................28
3.3.3 參考電位電路設計..................................29
3.3.4 直流側電壓感測電路設計.............................29
3.3.5 直流側過電壓保護電路設計...........................31
3.3.6 直流側過電流保護電路設計...........................32
3.3.7 閘極驅動電路設計..................................33
3.3.8 橋式轉換器電路設計................................34
3.4 多階層串聯橋式轉換器的建模.........................35
3.4.1 橋式轉換器平均切換模型.............................36
3.4.2 多階層星型串聯橋式轉換器簡易平均模型................39
3.4.3 MMCC-SSBC基於總體電壓平衡控制之簡化模型............44
第四章、機台實驗結果........................................50
4.1 簡介...............................................50
4.2 STATCOMs穩態之平衡操作I.............................54
4.2.1 總體電壓平衡控制積分增益的分析.....................54
4.2.2 總體電壓平衡控制比例增益的分析.....................64
4.2.3 電流控制比例增益的分析............................74
4.3 STATCOMs穩態之平衡操作II...........................84
4.3.1 總體電壓平衡控制積分增益的分析.....................84
第五章、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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