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研究生： 林柏志
Bo-Chih Lin
論文名稱： 低輸入電流漣波之三階LLC電能轉換器
Low Input Current Ripple Three Level LLC Power Converter
指導教授： 呂錦山
Ching-Shan Leu
口試委員: 邱煌仁
Huang-Jen Chiu
林瑞禮
Ray-Lee Lin
榮世良
Brady Jung
學位類別： 碩士
Master
系所名稱： 電資學院 - 電機工程系
Department of Electrical Engineering
論文出版年： 2014
畢業學年度： 102
語文別： 英文
論文頁數： 86
中文關鍵詞： 三階LLC電能轉換器 、自然平衡 、電流漣波消除 、高功率密度
外文關鍵詞： Three level LLC resonant converter, natural balance, current ripple reduction, higher power density
相關次數： 點閱：209  下載：33 
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    • LLC諧振轉換器具有零電壓切換、零電流切換、電路架構簡單以及效率高的特性。然而，欲提高轉換器的效率，一種使用了兩個串聯的開關達成低電壓應力的技術，並可降低開關上的導通損失。本文利用三階LLC架構取代半橋LLC架構，其三階LLC同樣具有零電壓及零電流切換，而開關上的應力被限制在輸入電壓的一半。第二章將分析及討論三階LLC。
    然而，三階LLC輸入電流仍有脈衝電流，進而造成EMI的問題。第三章提出一種低輸入電流漣波之三階LLC電能轉換器。該轉換器除了具有零電壓及零電流切換，其開關上的應力被限制在輸入電壓的一半，且無需任何的箝位機制及複雜的控制信號，其兩個串連的開關在不同的操作條件下均可達到電壓平衡。此外，尚可有效降低輸入電流漣波，使得EMI亦可有效降低，如此一來可以使用更小的EMI濾波器元件來滿足規範。因此，可以實現高功率密度的性能。
    文中將會探討三階LLC轉換器的工作模式、電路分析及電路設計。最後實現了一個低輸入電流漣波之三階LLC電能轉換器，其轉換器輸入電壓為直流300到400 V，輸出直流為24 V/10 A，輸出瓦數為240W，並經由實驗結果驗證及分析得出，該轉換器最高的效率在高壓半載為95.7%。

    The LLC resonant converter is widely used because of its attractive features such as zero-voltage switching (ZVS) of MOSFETs, zero-current switching (ZCS) of rectifier diodes, simple circuitry, and high efficiency.
    To enhance the efficiency performance, two low-voltage-rating switches connected in series with a voltage-clamped technique can be used to decrease the equivalent Rdson. Consequently, the MOSFET conduction loss is reduced. As an example, a half-bridge converter is modified to its three-level topology. Several three-level LLC (TL-LLC) converters have been addressed. In addition to having zero-voltage switching on the MOSFETs and zero-current switching on the rectifier diodes, the voltage stresses on the switches are limited to half input voltage. It will be investigated in Chapter 2.
    However, the input current of TL-LLC is pulsating and causes the EMI problems. To reduce the input current ripple, an input current ripple reduction mechanism can be applied to the TL-LLC and three level LLC (RR-TL-LLC) is thus investigated in Chapter 3. In addition to having zero-voltage switching on the MOSFETs and zero-current switching on the rectifier diodes, the voltage stresses on the switches are limited to half input voltage. Without any clamping mechanism and complicated control timing driver signals, the voltage balance between two series-connected switches are kept under different operating conditions. Moreover, it can effectively reduce the input current ripple. EMI regulation can be met by using smaller EMI filter components. Consequently, higher power density performance can be achieved.
    The operational principle, circuit analysis and design consideration are addressed. Finally, the RR-TL-LLC implementation with 300-400 V input, 24V/ 10A output power is built to verify theoretical analysis. The experimental results show that the maximum efficiency of the proposed converter is 95.7% under a high line half load.

    Abstract I Acknowledgements III Table of Contents IV List of Figures VI List of Table X Chapter 1 Introduction 1 1.1 Background and Motivation 1 1.2 Objectives of the Thesis 4 1.3 Organization of the Thesis 5 Chapter 2 Three Level LLC with Center-Tapped Rectification (TL-LLC-CT) 6 2.1 Introduction 6 2.2 Operational Principle 9 2.3 Circuit Analysis 19 2.3.1 Voltage gain 19 2.3.2 Decisions of k value 21 2.3.3 Decisions of Q value 23 2.4 Circuit Design 25 2.5 Experimental Results 32 2.5.1 Specification 32 2.5.2 Experimental Waveforms 33 2.5.3 Efficiency 36 2.5.4 Comparison with LLC 36 2.6 Summary 39 Chapter 3 Input Current Ripple Reduction with TL-LLC (RR-TL-LLC) 41 3.1 Introduction 41 3.2 Operational Principle 43 3.3 Circuit Analysis 54 3.3.1 Equivalent circuit of RR-TL-LLC 54 3.3.2 Input current ripple reduction 56 3.4 Circuit Design 57 3.4.1 Design of the resonant tank 58 3.4.2 Clamping capacitor 58 3.5 Experimental Results 59 3.5.1 Specification 59 3.5.2 Experimental Waveforms 60 3.5.3 Efficiency 63 3.5.4 Comparison with TL-LLC 63 3.6 Summary 66 Chapter 4 Conclusions and Future Research 68 4.1 Conclusions 68 4.2 Future Research 69 References 70

    [1] J. Jung, “Feed-forward compensator of operating frequency for APWM HB flyback converter,” IEEE Trans. Power Electron., vol. 27, no. 1, pp. 211–223, Jan. 2012.
    [2] W. Li, Y. He, X. He, Y. Sun, F. Wang, and L. Ma, “Series asymmetrical half-bridge converters with voltage autoblance for high input-voltage applications,” IEEE Trans. Power Electron., vol. 28, no. 8, pp. 3665–3674, Aug. 2013.
    [3] K. B. Park, C. E. Kim, G. W. Moon, and M. J. Youn, “PWM resonant single-switch isolated converter,” IEEE Trans. Power Electron., vol. 24, no. 8, pp. 1876-1886, Aug 2009.
    [4] B. Yang, F. C. Lee, A. J. Zhang, and G. Huang, “LLC resonant converter for front end dc/dc conversion,” in Proc. IEEE APEC, 2002, vol. 2, pp. 1108–1112.
    [5] H. Choi, “Design Considerations for an LLC Resonant Converter,” Fairchild Power Seminar, Korea, Tech. Rep. 82-3, 2007.
    [6] B. Lu, W. Liu, Y. Liang, F. C. Lee, and J. D. Van Wyk, “Optimal design methodology for LLC resonant converter,” in Proc. 21st Annu. IEEE APEC, Mar. 2006, pp. 533–538.
    [7] B. Yang, F. C. Lee, and M. Concannon, “Over current protection methods for LLC resonant converter,” in Proc. IEEE APEC, 2003, pp. 605–609.
    [8] B. Kim, K. Park, and G. Moon, “Asymmetric PWM control scheme during hold-up time for LLC resonant converters,” IEEE Trans. Ind. Electron., vol. 59, no. 7, pp. 2992–2997, Jul. 2012.

    [9] X. Fang, H. Hu, F. Chen, U. Somani, E. Auadisian, J. Shen, and I. Batarseh, “Efficiency-oriented optimal design of the LLC resonant converter based on peak gain placement,” IEEE Trans. Power Electron., vol. 28, no. 5, pp. 2285–2296, May 2012.
    [10] R. T. H. Li, M. F. Vancu, F. Canales, and D. Aggeler, “High performance dc-dc converter for wide voltage range operation,” in Proc. 7th Int. Power Electron. Motion Control Conf., Jun. 2012, vol. 2, pp. 1151–1158.
    [11] B. M. Song, R. McDowell, A. Bushnell, and J. Ennis, “A three-level dc–dc converter with wide-input voltage operation for ship-electric-power-distribution systems, ” IEEE Trans. Plasma Sci., vol. 32, no. 5, pp. 1856–1863, Oct. 2004.
    [12] J. Ke and R. Xinbo, “Hybrid full-bridge three-level LLC resonant converter- a novel DC-DC converter suitable for fuel cell power system,” IEEE PESC’05, 2005, pp. 361-367.
    [13] Y. Gu, Z. Lu, L. Hang, Z. Qian, and G. Huang, “Three-Level LLC series resonant DC/DC converter,” IEEE Trans. Power Electron., vol. 20, no. 4, pp. 781–789, Jul. 2005.
    [14] R. Wilkinson, H. du Mouton, and T. Meynard, “Natural balance of multi-cell converters: The two-cell case,” IEEE Trans. Power Electron., vol. 21, no. 6, pp. 1649–1657, Nov. 2006.
    [15] M. Khazraei, H. Sepahvand, K. Corzine, and M. Ferdowsi, “A generalized capacitor voltage balancing scheme for flying capacitor multilevel converters, ” in Proc. IEEE Appl. Power Electron. Conf. Expo., 2010, pp. 58–62.
    [16] H. Sheng, F. Wang, and C. W. Tipton, “A novel protection scheme for three-level converter based on monitoring flying capacitor voltage,” in Proc. IEEE-APEC, Feb. 2008, pp. 790–795.
    [17] X. Yuan, H. Stemmler, and I. Barbi, “Investigation on the clamping voltage self-balancing of the three-level capacitor clamping inverter,” in Proc. IEEE Power Electron. Spec. Conf., 1999, pp. 1059–1064.
    [18] X. Yuan, H. Stemmler, and I. Barbi, "Self-Balancing of the clamping- capacitor-voltages in the multilevel capacitor-clamping-inverter under sub-harmonic PWM modulation," IEEE Trans. Power Electron., vol. 16, no. 2, pp. 256-263, Mar 2001.
    [19] Francisco Canales, Peter Barbosa, and F. C. Lee. “A wide input voltage and load output variations fixed-frequency ZVS DC/DC LLC resonant converter for high-power applications” in Proceeding of PESC. 2002. pp.2306-2313.
    [20] A. Shukla, A. Ghosh, and A. Joshi, “Flying-capacitor-based chopper circuit for dc capacitor voltage balancing in diode-clamped multilevel inverter,” IEEE Trans. Ind. Electron., vol. 57, no. 7, pp. 2249–2261, Jul. 2011.
    [21] Xingkuan Guo, Xiaojun Deng, Jianhong Zeng, and Jianping Ying, “Analysis and solution to voltage unbalance of the flying capacitor in ZVS three level DC/DC converter, ” INTELEC, Sept. 2004, pp.684 – 688.
    [22] 鄒萍萍，鄒愛龍，王慧貞 “三電平逆變器直流側電容電壓平衡問題”南京航空航太大學 Nanjing University of Aeronautics and Astronautics 第十期2013年。
    [23] I. O. Lee and G. W. Moon, "Analysis and design of a three-level LLC Series resonant converter for high- and wide-input-voltage applications," IEEE Trans. Power Electron., vol. 27, no. 6, pp. 2966-2979, Jun. 2012.
    [24] C. S. Leu and Q. T. Nha, “A half-bridge converter with input current ripple reduction for DC distribution systems,” IEEE Trans. Power Electronics., vol. 28, no. 4, pp. 1756–1763, Apr. 2013.
    [25] C. S. Leu and N. T. Quang, “A novel half-bridge converter with current ripple reduction,” in Energy Conversion Congr. and Expo. (ECCE), Phoenix, AZ., Sept. 17-22, 2011, pp. 3954-3959.
    [26] S. D. Simone, C. Adragna, C. Spini, and G. Gattavari, “Design-oriented steady state analysis of LLC resonant converters based on FHA,” in Proc. IEEE SPEEDAM Conf., 2006, pp. 200–207.
    [27] J. Hou, “Design procedure for LLC resonant converter,” M.S. thesis, Dept. Commun. and Electron. Eng. College of Elect. Eng. and Comput. Sci., Nat. TaiwanTech Univ., Taipei, TaiwanTech, 2009.
    [28] I. O. Lee and G. W. Moon, “The k-Q analysis for an LLC series resonant converter,” IEEE Trans. Power Electronics., vol. 29, no. 1, pp. 13–16, Jan. 2014.
    [29] AN-2450 application note, “LLC resonant half-bridge converter design guideline”, ST Microelectronics, 2007.
    [30] AN-4151 application note, “Half-bridge LLC resonant converter design using FSFR-series Fairchild power switch”, Fairchild Semiconductor, 2007.
    [31] TDK’s European website for electronic components & systems [Online]. Available: http://www.tdk.co.jp/tefe02/e141.pdf
    [32] SIMetrix Technologies Ltd. (2012). SIMPLIS reference. [Online]. Available: http://www.simetrix.co.uk//Files/manuals/6.2/SIMPLIS_Reference.pdf
    [33] SIMetrix Technologies Ltd. (2012). User’s manual. [Online]. Available: http://www.simetrix.co.uk/Files/manuals/6.2/UsersManual.pdf
    [34] C.S. Leu and P.Y. Huang, “Near zero current-ripple inversion or rectification circuits,” U.S. Patent 8,665,616 B2, Mar. 4, 2014.

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