本論文呈現一台高效率堆疊輸出電壓充電器，主要是設計適用於不同電池陣列的充電器，因此充電器的輸出電壓範圍較為廣泛。充電器在經由堆疊輸出電壓的設計方式，提高在寬範圍輸出電壓時變壓器的利用率與效率表現。為了瞭解本論文提出電路的可行性與設計概念的優異性，文中首先將介紹與分析兩個傳統的架構將，第一個架構是單級式架構，所選用的電路架構為全橋相移轉換器。第二個架構是兩級式架構，所選用的架構分別為全橋串聯諧振轉換器與降壓型轉換器，與兩級式架構相比，由相關數據分析可以得知堆疊式架構可以改善效率的表現。堆疊式架構的輸出電壓結構是使用兩個電壓堆疊，一個是固定電壓，另一個是可變的電壓。針對電池充電的應用，定電壓與定電流充電電路也可以與堆疊式架構整合實現。本文最後實作出兩個3.3 kW的單級式架構與堆疊式架構，經由測試結果來驗證本論文提出的設計概念的可行性。

This dissertation presents a high-efficiency battery charger with cascode output design. The presented battery charger is designed for charging different battery banks, so the output voltage range is wider. By using cascode output voltage, the proposed scheme improves the transformer utilization and the efficiency performance under wide range output voltage. To show the feasibility and superiority of the proposed circuit, two conventional battery chargers are discussed and analyzed. Firstly, a single-stage topology is implemented by phase-shifted full-bridge converter. Secondly, a two-stage topology is implemented by full-bridge series-resonant converter and buck converter. The proposed cascode topology improves the efficiency performance compared with the two-stage topology. The output stage is a cascode structure comprising fixed voltage and variable voltage. The constant current and constant voltage charging schemes can be achieved by the proposed cascode configuration for battery charger applications. Two 3.3-kW laboratory prototypes of the single-stage scheme and the proposed topology are implemented and tested. The experimental results are shown to verify the feasibility of the proposed scheme.

[1] A. F. Bakan, N. Altintas, and I. Aksoy, "An improved PSFB PWM DC–DC converter for high-power and frequency applications," IEEE Transactions on Power Electronics, vol. 28, no. 1, pp. 64-74, Jan. 2013.
[2] I. H. Cho, K. M. Cho, J. W. Kim, and G. W. Moon, "A new phase-shifted full-bridge converter with maximum duty operation for server power system," IEEE Transactions on Power Electronics, vol. 26, no. 12, pp.3491-3500, Dec. 2011.
[3] X. Wu, J. Zhang, G. Wu, and Z. Qian, "High efficiency phase-shift controlled hybrid full bridge DC bus converter," in Proc. APEC, 2006, pp. 1333-1338.
[4] I. O. Lee, S. Y. Cho, and G. W. Moon, "Three-level resonant converter with double LLC resonant tanks for high-input-voltage applications," IEEE Transactions on Industrial Electronics, vol. 59, no. 9, pp. 3450-3463, Sept. 2012.
[5] R. Beiranvand, B. Rashidian, M. R. Zolghadri, and S. M. H. Alavi, "A design procedure for optimizing the LLC resonant converter as a wide output range voltage source," IEEE Transactions on Power Electronics, vol. 27, no. 8, pp. 3749-3763, Aug. 2012.
[6] K. A. Cho, S. H. Ahn, S. B. Ok, H. J. Ryoo, S. R. Jang, and G. H. Rim, "Design of LCC resonant converter for renewable energy systems with wide-range input voltage," in Proc. IPEMC, 2012, pp.1221-1228.
[7] J. H. Jung, H. S. Kim, J. H. Kim, M. H. Ryu, and J. W. Baek, "High efficiency bidirectional LLC resonant converter for 380V DC power distribution system using digital control scheme," in Proc. APEC, 2012, pp. 532-538.
[8] R. Beiranvand, B. Rashidian, M. R. Zolghadri, and S. M. H. Alavi, "Optimizing the normalized dead-time and maximum switching frequency of a wide-adjustable-range LLC resonant converter," IEEE Transactions on Power Electronics, vol. 26, no. 2, pp. 462-472, Feb. 2011.
[9] R. L. Lin and C. W. Lin, "Design criteria for resonant tank of LLC DC-DC resonant converter," in Proc. IECON, 2010, pp. 427-432.
[10] C. Nagarajan and M. Madhswaran, "Analysis and simulation of LCL series resonant full bridge converter using PWM technique with load independent operation," in Proc. ICTES, 2007, pp 190-195.
[11] B. Yang, F. C. Lee, A. J. Zhang, and G. Huang, "LLC resonant converter for front end DC/DC conversion," in Proc. APEC, 2002, pp. 1108-1112.
[12] B. Gu. C. Y. Lin, B. F. Chen, J. Dominic, and J. S. Lai, "Zero-voltage-switching PWM resonant full-bridge converter With minimized circulating losses and minimal voltage stresses of bridge rectifiers for electric vehicle battery chargers," IEEE Transactions on Power Electronics, vol. 28, no. 10, pp. 4657-4667, Oct. 2013.
[13] J. Dudrik, P. Spanik, and N. D. Trip, "Zero-voltage and zero-current switching full-bridge DC-DC converter with auxiliary transformer," IEEE Transactions on Power Electronics, vol. 21, no. 5, pp. 1328-1335, Sept. 2006.
[14] X. Wu, J. M. Zhang, and Z. Qian, "Optimum design considerations for a high efficiency ZVS full bridge DC-DC converter," in Proc. INTELEC, 2004, pp. 338-344.
[15] G. B. Lima, D. B. Rodrigues, A. V. Costa, L. C. Freitas, E. A. A. Coelho, V. J. Farias, and L. C. G. Freitas, "Novel proposal of hybrids rectifiers with voltage sag ride-through capability based on series DC voltage compensation technique," in Proc. APEC, 2013, pp. 2162-2170.
[16] M. Tomlinson, D. Abrie, and T. Mouton, "Series-stacked medium voltage electronic voltage regulator," in Proc. ECCE, 2011, pp. 1087-1093.
[17] S.H. Cho, C. W. Roh, S. S. Hong, and S. K. Han, "High efficiency and low cost tightly regulated dual output LLC resonant converter," in Proc. ISIE, 2010, pp. 862-869.
[18] L. J. Hang, Y. L. Gu, Z. Y. Lu, Z. M. Qian, and D. H. Xu, "Magamp post regulation for LLC series resonant converter with multi-output," in Proc. IECON, 2005, pp. 628-632.
[19] Q. Chen, F. C. Lee, and M. M. Jovanovic, "Analysis and design of multiple-output converters with stacked secondaries," in Proc. INTELEC, 1993, pp. 365-371.
[20] J. P. Agrawal and I. Batarseh, "Improving the dynamic and static cross regulation in multi-output resonant converters," in Proc. APEC, 1993, pp. 65-70.
[21] R. Yu, B. M. H. Pong, B. W. K. Ling, and J. Lam, "Two-stage optimization method for efficient power converter design including light load operation," IEEE Transactions on Power Electronics, vol. 27, no. 3, pp. 1327-1337, March 2012.
[22] Z. Emami, M. Nikpendar, N. Shafiei, and S. R. Motahari, "Leading and lagging legs power loss analysis in ZVS phase-shift full bridge converter," in Proc. PEDSTC, 2011, pp. 632-637.
[23] Y. Chen, P. Asadi, and P. Parto, "Comparative analysis of power stage losses for synchronous buck converter in diode emulation mode vs. continuous conduction mode at light load condition," in Proc. APEC, 2010, pp. 1578-1583.
[24] B. Y. Chen and Y. S. Lai, "Switching control technique of phase-shift-controlled full-vridge converter to improve efficiency under light-load and standby conditions without additional auxiliary components," IEEE Transactions on Power Electronics, vol. 25, no. 4, pp. 1001-1012, April 2010.
[25] O. Abdel-Rahman, J. A. Abu-Qahouq, L. Huang, and I. Batarseh, "Analysis and design of voltage regulator with adaptive FET modulation scheme and improved efficiency," IEEE Transactions on Power Electronics, vol. 23, no. 2, pp. 896-906, March 2008.
[26] Y. Ren, M. Xu, J. Zhou, and F. C. Lee, "Analytical loss model of power MOSFET," IEEE Transactions on Power Electronics, vol. 21, no. 2, pp. 310-319, March 2006.
[27] W. Zhang, Y. Liu, Z. Li, and X. Zhang, "The dynamic power loss analysis in buck converter," in Proc. IPEMC, 2009, pp. 362-367.