本論文主旨在研製一台高效能雙向三相直流-直流轉換器，應用於直流微電網中做電氣隔離。電路架構為輸入側三臂半橋(六個開關)、三組諧振槽、三個隔離變壓器與輸出側三臂半橋開關所組成。三個變壓器以Y-Y接法的三相變壓器方式連結，相較於一般全橋轉換器，三個變壓器平均分擔總輸出功率，如此能夠減小鐵芯體積；開關控制部分採用每一臂控制信號相位相差120°，輸入側的開關皆達到零電壓切換。
本文首先介紹半橋串聯諧振轉換器，接著探討雙向三相直流-直流轉換器，分析其各個階段的動作原理與推導諧振槽之轉移函數，並利用數學軟體Mathcad繪製出增益曲線。最後實作出一台輸出功率8 kW的實體電路，在不同負載下整體轉換效率在95%以上。

The thesis presents the study and implementation of a high performance bidirectional three-phase DC-DC converter, which can isolate for DC micro-grid systems. The power circuit consists of three half-bridge switch legs (six switches) at input port, three resonant tanks, three isolated transformers and three half-bridge switch legs at output port. The three isolated transformers are configured in Y-Y connection. Compared with general single-transformer full-bridge configuration, it can share output power by three transformers, the size and cost of each transformer are thus reduced. The control signal has a phase-shift of 120° between each leg, the zero-voltage-switching can be achieved at input port.
First this thesis introduce half-bridge series resonant converter, and study the three phase Y-Y bidirectional resonant converter, The operation principles are analyzed and transfer function of the resonant tank is concluded. Then, a mathematical software Mathcad is used to plot the curve of voltage gain. Finally, a laboratory prototype with 8 kW rated power has been built and tested, the measured efficiencies are above 95% at different load conditions.

[1] B. Kroposki, D. Mooney, T. Markel, and B. Lundstrom, “Energy Systems Integration Facilities at the National Renewable Energy Laboratory,” in Proc. Energytech, 2012, pp. 1-4.
[2] 廖日能，並聯型三臂式直流-直流功率轉換器之研製，國立台灣科技大學電子工程系碩士論文，2009年。
[3] 王釗桴，高功率隔離型雙向三相直流-直流轉換器研製，國立台灣科技大學電子工程系博士論文，2014年。
[4] 張永瑞、姜政綸、李奕德，「微電網發展前景與技術剖析」，台灣能源期刊，第二卷，頁數259-278，2013年9月。
[5] 林常平、陳貽評，「電網發展歷程與未來展望」，能源報導，頁數5-7，2011年9月。
[6] 陳貽評、彭兆國，「微電網概述」，電力人，第十六期，頁數15-19，2014年11月。
[7] F. Kaitiraei, “Microgrid management,” IEEE Power & Energy, Vol. 6, No. 3, pp. 54-65, May/June 2008.
[8] Rejeki Simanjorang, H. Yamaguchi, H. Ohashi, K. Nakao, T. Ninomiya, S. Abe, M. Kaga, and A. Fukui, “High-Efficiency High-Power dc-dc Converter for Energy and Space Saving of Power-Supply System in a Data Center,” in Fort Worth, Texas. APEC, 2011, pp. 600-605.
[9] Wonok Kwon and Hagyoung Kim, “DC Power Shared Data Center Configuration for Cloud Computing,” in Korea. ICTC, 2015, pp. 1279-1282.

[10] Du-Hwan Kim, Taesik Yu, Hyosung Kim, Hyungsoo Mok, and Kyung-Seok Park, “300V DC Feed System for Internet Data Center,” in Korea. 8th International Conference on Power Electronics - ECCE Asia, 2011, pp. 2352-2358.
[11] 林文仁，以三階層升壓電路實現太陽能供電之獨立直流微電網系統，國立交通大學電控工程研究所碩士論文，2010年。
[12] 吳財富，「綠色能源直流供電系統介紹」，98學期第一學年中正講座，中正大學，2009年。
[13] 林建宏，整合不同電源型態之直流微電網併接技術之研究，國立中山大學電機工程學系研究所碩士論文，2011年。
[14] Daniel Salomonsson, Lennart Söder, and Ambra Sannino, “An Adaptive Control System for a DC Microgrid for Data Centers,” IEEE Transactions on Industry Applications, Vol. 44, NO. 6, pp. 1910-1917, November/December 2008.
[15] Dustin J Becker and B.J. Sonnenberg “DC Microgrids in Buildings and Data Centers,” in Amsterdam, Netherlands. INTELEC, 2011, pp. 1-7.
[16] 謝維銘，數位控制高功率三相隔離型直流-直流轉換器研製，國立台灣科技大學電子工程系碩士論文，2014年。
[17] 楊恩湧，具自然換向之隔離型雙向諧振轉換器研製，國立台灣科技大學電子工程系碩士論文，2015年。
[18] 邱柏晟，雙向全橋隔離型直流/直流電源轉換器研製，國立台灣科技大學電子工程系碩士論文，2015年。
[19] 蔡富斌，具同步整流之數位控制半橋串聯諧振轉換器之研製，國立台灣科技大學電子工程系碩士論文，2012年。
[20] 彭譽耀，交錯式半橋串聯諧振轉換器研製，國立台灣科技大學電子工程系碩士論文，2012年。
[21] 陳建宇，二次側諧振槽串聯諧振轉換器頻率調變策略研究，國立台灣科技大學電子工程系碩士論文，2010年。
[22] R. Mirzahosseini and F. Tahami, “A Phase-Shift Three-Phase Bidirectional Series Resonant DC/DC Converter,” in Melbourne, Australia. IECON, 2011, pp. 1137-1143.
[23] Joep Jacobs, Andreas Averberg, and Rik De Doncker, “A Novel Three-phase DC/DC Converter for High-Power Applications,” PESC, 2004, pp. 1861-1867.
[24] Joep Jacobs, Andreas Averberg, and Rik De Doncker, “Multi-Phase Series Resonant DC-to-DC Converters: Stationary Investigations,” PESC, 2005, pp. 660-666.
[25] M. I. Nassef, H. A. Ashour, and H. Desouki, “Battery-less hybrid micro-grid power management using bi-directional three phase power converter,” in USA. ICDCM, 2015, pp. 19-25.
[26] Gui-Jia Su and Lixin Tang, “A Three-Phase Bidirectional DC-DC Converter for Automotive Applications,” in Canada. IAS, 2008, pp. 1-7.
[27] 吳宗澤，雙向諧振直流電源轉換器之設計與研製，國立清華大學碩士論文，2010年。
[28] Ashoka K. S. Bhat and Raymond L. Zheng, “A Three-phase Series-Parallel Resonant Converter-Analysis, Design, Simulation, and Experimental Results,” IEEE Transactions on Industry Applications, Vol. 32, NO. 4, pp. 951-960, July/August 1996.
[29] Demercil S. Oliveira, Jr. and Ivo Barbi, “A Three-Phase ZVS PWM DC/DC Converter With Asymmetrical Duty Cycle Associated With a Three-Phase Version of the Hybridge Rectifier,” IEEE Transactions on Power Electronics, Vol. 20, No. 2, pp. 354-360, March 2005.

[30] 吳義利編著，切換式電源轉換器原理與實用設計技術，文笙書局股份有限公司，民國101年。
[31] Cree, “C2M0025120D” Technical Information, Data Sheet, 2014.