本論文主要提出一混合模式控制之推挽式SEPIC功率因數修正器(Power Factor Corrector, PFC)，目的是使PFC在同一個輸入電壓週期下同時具有邊界導通模式(Transition Mode, TM)和連續導通模式(Continuous Conduction Mode, CCM)。
邊界導通模式推挽式SEPIC PFC之功率開關導通時具有波谷切換(Valley-Switching)，其切換損耗(Switching Loss)近似為零；但電感電流漣波較大，此特性會造成功率級元件之導通損耗(Conduction Loss)增加，當負載越重時損耗越大。當電路操作在連續導通模式下輸出二極體具有逆向恢復電流，導致功率開關在導通時之切換損耗增加，當負載越輕載時此現象越明顯；但連續導通模式之電感電流漣波較小，此特性使電路在重載時功率級元件之導通損耗較小。所以本論文提出一混合模式控制電路，使PFC結合兩種操作模式，可在一個輸入電壓週期下同時存在邊界導通與連續導通兩種模式，結合了上述兩種電流模式之優點，也消除各自之缺點。
本論文對推挽式SEPIC功率因數修正器之動作原理作分析與討論，配合SIMetrix/SIMPLIS軟體之模擬，實際完成一台輸入電壓範圍為90 Vac~264 Vac、輸出為200 V/300 W之單級電源轉換器。

The main purpose of this thesis is to propose a mixed-mode controlled push-pull SEPIC Power Factor Corrector (PFC). Both the continuous conduction mode (CCM) and the transition mode (TM) operate during one same line-frequency cycle in the proposed PFC. Under TM operations, quasi-resonant (QR) valley-switching on the switches can reduce the switching losses. However, the higher inductor current ripple increases the conduction losses of the switches, which is more obvious as the load increases. Under CCM operations, the output diode has reverse recovery problem that results in a higher switching loss, which is obvious at light load. Nevertheless, under CCM operations, the smaller inductor current ripple reduces the conduction losses of the switches. A mixed-mode controlled PFC controller is proposed in this thesis. By applying both CCM and TM operations during one same line-frequency cycle, the advantages can be maintained and the disadvantages be eliminated.
The operation principles of push-pull SEPIC power factor corrector are described, analyzed and discussed in detail. The computer simulation software, SIMetrix/SIMPLIS, is applied for circuit analysis. Experimental results have been verified with the theoretical analysis over an input voltage range of 90 Vac to 265 Vac and an output power of 200 V/300 W.

[1] A. I. Pressman, “Switching Power Supply Design” Third Edition, McGraw-Hill, 2009.
[2] 林建宇，「雙模式升壓型功率因數修正器最佳化設計」，國立臺灣科技大學電子工程系研究所碩士論文，民國99年。
[3] 鄭振東，「新型柔性切換式電源技術入門」，全華科技圖書股份有限公司，民國92年。
[4] N. Mohan, T. M. Undeland and W. P. Robbins, “Power Electronics Converters, Applications, and Design,“ John Wiley & Sons Inc., 3rd Edition, 2003.
[5] 許元豪，「徹底剖析工作於連續導通模式下升壓型PFC 線路中高壓快速恢復二極管所導致的五種功率損耗模式」，電子月刊UPS/SPS資訊電源專輯–PFC技術–電源品質保證，2008年2月。
[6] C. Adragna, S. De Simone, and G. Gattavari, “New fixed off-time PWM modulator provides constant frequency operation in boost PFC pre-regulators,” International Symposium on Power Electronics, Electrical Drives, Automation and Motion, 2008, pp. 656-661, 11-13 Jun. 2008.
[7] ST Microelectronics, “Design of fixed-off-time-controlled PFC pre-regulators with the L6562,” AN1792, Application Note, Nov. 2003.
[8] 陳彥捷，「雙模式控制返馳式轉換器最佳化設計」，國立台灣科技大學電子工程系研究所碩士論文，民國100年。
[9] 林忠義，「推挽式升壓型功率因數修正器之分析與設計」，國立台灣科技大學電子工程系研究所博士論文，民國99年。

[10] E. Jayashree, G. Uma, “Design and implementation of zero-voltage switching quasi-resonant positive-output Luo converter using analog resonant controller UC3861,” IET Power Electronics., vol. 14, no. 1, pp. 81-88, Jan. 2011.
[11] 謝儲仲，「寬輸入電壓範圍之雙組輸出半橋LLC串聯諧振轉換器研製」，國立台灣科技大學電子工程系研究所碩士論文，民國98年。
[12] 鄭玉南，「返馳式轉換器緩振電路研究」，國立臺灣科技大學電子工程系研究所碩士論文，民國95年。
[13] 陳家麟，「具功率因數修正關閉之主動箝位返馳式轉換器研製」，國立臺灣科技大學電子工程系研究所碩士論文，民國98年。
[14] 梁適安 著，「交換式電源供應器之理論與實務設計」，民國83年，全華科技圖書。
[15] K. de Gussemé, D. M. V. de Sype, A. P. M. V. den Bossche, and J. A. Melkebeek, “Input-current distortion of CCM boost PFC converters operated in DCM,” IEEE Trans. Industrial Electronics., vol. 54, no. 2, pp. 858-865, Apr. 2007.
[16] B. Choi, S.-S. Hong, and H. Park, “Modeling and small-signal analysis of controlled on-time boost power-factor-correction circuit,” IEEE Trans. Industrial Electronics., vol. 48, no. 1, pp. 136-142, Feb. 2001.
[17] 鄭世仁，「一般照明應用高效率可調光LED驅動器之研製」，國立台灣科技大學電子工程系研究所博士論文，民國99年。
[18] 曾軍皓，「高效能功率因數修正器研製」，國立台灣科技大學電子工程系研究所碩士論文，民國95年。

[19] J. M. Kwon, W. Y. Choi, J. J. Lee, E. H. Kim, and B. H. Kwon, “Continuous-conduction-mode SEPIC converter with low reverse-recovery loss for power factor correction,” IEE Proc.-Elect. Power Applications, vol.153, no.5, pp.673-681, Sep. 2006.
[20] H. J. Chiu and S. J. Cheng, “Design considerations of an SEPIC PFC converter for driving multiple lighting LED lamps,” International Journal of Circuit Theory and Applications, vol.37, issue 8, pp. 928-940, Oct. 2009.
[21] D. WeiHua , Z. Bo, D. Guiping and H. ZongBo “Couple inductor design with small voltage spike of SEPIC converter,” the 20th IEEE Applied Power Electronics Conference and Exposition Conference, vol. 3, pp. 1922-1926, 2005.
[22] ST Microelectronics, “TM sepic converter in PFC pre-regulator,” AN2435, Application Note, Mar. 2007.
[23] ST Microelectronics, “ L6561, POWER FACTOR CORRECTOR,” Data Sheet, 2003.