考量電感隨電流增大而衰減之特性的分切合整直接數位控制法，可透過回授電流來估算電感的衰減值，並納入開關責任比率的計算，屬於具高電感衰減容忍度的控制法。而在濾波器設計上，若能接受較大的衰減量，將能選擇體積較小之鐵芯，促使系統能朝向高功率密度發展。因此本研究實現兩組具不同電感衰減容忍度(15% & 75%)之換流器，來分析兩者的差異，與驗證換流器因採用具高電感衰減容忍度的控制法則，能有效縮小濾波電感的體積，提升系統功率密度。
本研究之兩組換流器在規格與架構上完全相同，皆使用三相三線LCL全橋式拓樸，其中LCL濾波器相較具有相同濾波效果的LC濾波器，會有較小的體積。在韌體和控制方面，則以微控制器Renesas RX71M作為處理核心，其快速的A/D轉換速率可因應較高的切換頻率(100 kHz)。採用三角載波計時器和波峰取樣/波谷更新模式，以取得電感電流變化量之平均值。
比較兩組具不同電感衰減容忍度之換流器的前提，為兩者在相同的額定功率下，擁有相似的濾波效果。因此本論文回顧LCL濾波器設計文獻，並使用限制電感最大電流漣波之理論來推導所需的濾波電感值。濾波電容選用傳統的方法，依據換流器在額定功率下所吸收的虛功多寡進行設計。設計結果的合理性則以三項限制條件來判斷，包含：總電感值上限、諧振頻率帶及諧振頻率間距。此外，本研究方法還透過鐵芯資訊，加入篩選適用鐵芯之程序，並以Matlab加速反覆計算的過程，使設計的結果得以直接採納。
於末章，本論文透過模擬工具(Matlab/Simulink)來確認系統的動態響應和濾波能力，並實測兩組系統的基本功能與電壓/電流總諧波失真率，接著利用各項數據分析兩組系統之差異，包含電感值、THD、損耗、體積及溫度。
本研究之主要貢獻為：(1)設計具寬電感變化的LCL濾波器，除了使換流器輸出電流總諧波失真率能符合規範外，也得以讓兩組具不同電感衰減容忍度之換流器在額定功率下，有相似的濾波能力。(2)實作兩部具備功率因數調整能力的三相三線LCL全橋式換流器。(3)換流器採用具高電感衰減容忍度的分切合整直接數位控制法，證明在濾波器設計上，能選擇體積較小之鐵芯，促使系統能朝向高功率密度的發展。

The decoupled direct digital control taking the inductance variation into account can estimate the inductance attenuation with currents. It is a control method with high inductance attenuation toleration. With regarding to filter design, if an inverter can tolerate a larger amount of inducatance attenuation, the overall filter inductor size can be reduced to promote the development of the system towards high power density. Therefore, this research is to design and implement two inverters with different inductance attenuation tolerance (15% & 75%). In addition to verifying the above statement, it analyzes the characteristic difference between the two systems.
The two inverters adopt the same specifications and configuration. They are three-phase three-wire LCL full-bridge topologies. Compared with an LCL filter, the inductor size of an LC filter is larger under the same filtering capability. To control the systems, a Renesas RX71M microcontroller which has fast conversion rate is used as the processing unit to meet high frequency switching demand. Besides, the systems adopt the triangular carrier timer and the sample at crest/update at through mode to obtain the average value of the inductor current variation.
The premise of comparing two inverters with different inductance attenuation tolerance is that they have similar filtering capability under the same rated power. Consequently, this thesis reviews the LCL filter design and uses the scheme of limiting the maximum current ripple of the inductor to derive the required filter inductance value. The filter capacitor is designed with a conventional method according to the amount of reactive power absorbed by the inverter under the rated power. The design results are judged by three constraints, including the upper limit of the total inductance, the resonant frequency band and the resonant frequency spacing. In addition, the LCL filter design method of this research adds the process of screening out unsuitable cores, and uses Matlab to accelerate the calculation process, so the design results can be directly adopted.
Finally, the basic function, dynamic response and filtering capability of the two systems are verified by simulated (Matlab/Simulation) and experimental results. Additionally, the differences between the two systems in terms of inductance, THD, loss, volume and temperature are analyzed.
The major contributions of this thesis are : (1) designing LCL filters with a wide inductance variation which can be not only achieve the output currents complying with the regulation, but make the two inverters with defferent inductance attenuation tolerances have similar filting capability under the same rated power, (2) implementing two 33 kW three-phase three-wire LCL full-bridge inverters with the capability of injecting active and reactive power into the grid, and (3) verifying that the volume of the filter inductor can be effectively reduced, and the power density of the inverter can be increased due to the use of the decoupled direct digital control with high inductance attenuation tolerance.

摘要 i
Abstract iii
誌謝 v
目錄 vi
圖目錄 viii
表目錄 xii
第一章 緒論 1
1-1研究背景與動機 1
1-2文獻回顧 2
1-2-1 電感衰減接受度與濾波元件體積關係 2
1-2-2換流器控制法簡介 4
1-2-3 LCL濾波器簡介 6
1-2-4 LCL濾波器設計簡介 9
1-3論文大綱 11
第二章 LCL濾波器設計 12
2-1換流器拓樸 12
2-2 LCL濾波器設計 13
2-2-1直流側電感設計 14
2-2-2電網側電感設計 22
2-2-3濾波電容設計 23
2-2-4限制條件 24
2-2-5設計流程 29
第三章 系統架構與控制法則 36
3-1換流器硬體架構 36
3-2解耦合分切合整直接數位控制法則 37
第四章 韌體架構與規劃 45
4-1韌體架構 45
4-2微控制器RX71M介紹與設定 46
4-3韌體程式流程 51
4-3-1主程式流程 51
4-3-2中斷副程式流程 52
第五章 系統模擬與實測 60
5-1系統規格 60
5-2元件參數設計與選用 61
5-3實務考量 64
5-4模擬與實測波形 66
5-4-1 Matlab/Simulink 模擬 66
5-4-2容忍度15%之換流器模擬與實測波形 69
5-4-3容忍度75%之換流器模擬與實測波形 79
5-4-4含電網諧波成分的模擬結果 89
5-5比較與分析 91
5-5-1電感初始值 91
5-5-2輕載THD 92
5-5-3損耗 93
5-5-4體積 100
5-5-5溫度 101
第六章 結論與未來研究方向 105
6-1結論 105
6-2未來研究方向 106
參考文獻 107

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