本論文係以對角半橋型順向式DC/DC電力轉換器(Diagonal Half-Bridge Forward DC/DC converter)為研究主題，簡稱為DHBF電力轉換器，吾人將此轉換器結合ZVT-PWM柔性切換技術，設計出零電壓切換對角半橋型順向式DC/DC電力轉換器(ZVT-PWM DHBF DC/DC　converter)，此轉換器具有高電力轉換效率。

　　傳統DHBF電力轉換器之對角開關係屬於硬性切換。若欲使對角開關達到柔性切換，須於切換前使對角開關之端電壓共振至零。

　　本論文所提出的ZVT-PWM DHBF電力轉換器，係於DHBF電力轉換器之變壓器一次側並接輔助電路，此輔助電路包含輔助開關、共振電感及共振電容。吾人利用輔助開關控制共振時機，使對角開關達到零電壓切換，並且輔助開關亦可達到零電流切換，有效地提升轉換器之效率。此外，吾人將變壓器二次側之輸出整流電路，引入同步整流技術(synchronous rectification technique)，使轉換器操作於重載時具有高電力轉換效率。

　　針對本論文所提出之ZVT-PWM DHBF電力轉換器，吾人對轉換器進行動作原理及理論分析，並利用IsSpice模擬與電路實作，以驗證理論推導之正確性。最後，完成一組規格為輸入電壓 、輸出電壓為 、輸出電流 、輸出功率 且轉換效率達 的電力轉換器。藉由本論文所提出的ZVT-PWM DHBF DC/DC電力轉換器，可驗證柔性切換技術與同步整流技術之功效。

　　Based on the Diagonal Half-Bridge Forward (DHBF) DC/DC converter and soft switching technique, a novel Zero-Voltage-Transition Pulse-Width Modulation (ZVT-PWM) DHBF DC/DC converter is proposed in this thesis. It has high power conversion efficiency.

　　The diagonal switches of the conventional DHBF converter exhibits hard switching. To achieve soft-switching operation, the voltages of the diagonal switches must resonate down to zero before switching.

　　The proposed converter is developed by paralleling an auxiliary circuit at primary side of the transformer of the DHBF converter. The auxiliary circuit comprises a resonant inductor, a resonant capacitor and an auxiliary switch, which is used to control resonant occurrence. The diagonal switches of the proposed converter can operate under zero-voltage switching (ZVS) and the auxiliary switch can also operate under zero-current switching (ZCS). It is effective to increase the efficiency of the converter. Moreover, the synchronous rectification technique is also employed to reduce the conduction losses of the output rectifier. As a result, the proposed converter still exhibits high efficiency at heavy load.

　　The operation principle and theoretical analysis of the proposed converter are presented herein. They are validated by IsSpice simulations and experimental results. A prototype of ZVT-PWM DHBF converter for input and / output is finally implemented. The overall efficiency of the proposed converter achieves at full load. The efficiency of the soft switching technique and the synchronous rectification technique is demonstrated by the proposed ZVT-PWM DHBF DC/DC converter.

[AbB00] Abu-Qahouq, J. and I. Batarseh, “Generalized Analysis of Soft-Switching DC-DC Converters,” IEEE PESC, pp. 185-192, 2000.

[BBML90] Barbi, I., J. C. O. Bolacell, D. C. Martin and F. B. Libano, “Buck Quasi-Resonant Converter Operating at Constant Frequency: Analysis, Design and Experimentation,” IEEE Trans. on Power Electronics, Vol. 5, No. 3, pp. 276-283, 1990.

[BoB02] Bodur, H. and A. F. Bakan, “A New ZVT-PWM DC-DC Converter,” IEEE Trans. on Power Electronics, Vol. 17, No. 1, pp. 40-47, 2002.

[BSHG01] Baggio, J.E., L. Schuch, H.L. Hey, H.A. Grundling, H. Pinheiro and J.R. Pinheiro, “Quasi-ZVS Active Auxiliary Commutation Circuit for Two Switches Forward Converter,” IEEE PESC, pp. 398-403, 2001.

[ChL97] Chen, Y. T. and W. H. Liu, “The Implementation and Analysis for The ZVS PWM Forward Converter Using a Saturable Circuit,” Proceedings of the 18th Symposium on Electrical Power Engineering, R.O.C., pp. 328-333, 1997.

[CXM02] Chen, M., D. Xu and M. Matsui, “Study on Magnetizing Inductance of High Frequency Transformer in the Two-Transistor Forward Converter,” IEEE PCC, pp. 597-602, 2002.

[Eri99] Erickson, R. W., Fundamentals of Power Electronics, Kluwer Academic Publishers, Massachusetts, 1999.

[GhM02] Ghodke, D.V., and K. Muralikrishnan, “1.5 kW Two Switch Forward ZCZVS Converter Using Primary Side Clamping,” IEEE PSEC, pp. 893-898, 2002.

[HeS98] Hey, H. L. and C. M. O. Stein, “A New Family of Soft-Switching DC-DC PWM Converters Using a True ZCZVT Commutation Cell,” IEEE IECON, pp. 1030-1035, 1998.

[HLL92] Hua, G., C. S. Leu and F. C. Lee, “Novel Zero-Voltage-Transition PWM Converters,” VPEC Seminar, pp. 81-88, 1992.

[HLWL] Hsieh, G. C., M. F. Lai, J. P. Wang and M. H. Lia, “Realization Study of Isolated Half-Bridge Zero-Voltage-Switched Converter,” IEEE IECON, pp. 663-668, 1994.

[HuL95] Hua, G. and F. C. Lee, “Soft-Switching Techniques in PWM Converters,” IEEE Trans. on Industrial Electronics, Vol. 42, No. 6, pp. 595-603, 1995.

[JJJ01] Jain, N., P. Jain and G. Joos, “Analysis of a Zero Voltage Transition Boost Converter Using a Soft Switching Auxiliary Circuit with Reduced Conduction Losses,” IEEE PESC, pp. 1799-1804, 2001.

[JoY00] Jovanovic, M. M. and J. Yungtaek, “A Novel Active Snubber for High-Power Boost Converters,” IEEE Trans. on Power Electronics, Vol. 15, No.2, pp. 278-284, 2000.

[JTL89] Jovanovic, M. M., W. A. Tabisz and F. C. Lee. “High-Frequency Off-Line Power Conversion Using Zero-Voltage-Switching Quasi-Resonant and Multiresonant Techniques,” IEEE Trans. on Power Electronics, Vol. 4, No. 4, pp. 459-469, 1989.

[LHY04] Lin, J. L., J. C. Hsieh and I. C. Yeh, “A Novel ZCZVT Soft-Switching Single-Stage High Power Factor Correction Converter,” IEEE Asia-Pacific Conference on Circuits and Systems, Vol. 2, pp. 657-660, 2004.

[LiC03] Lin, J. L. and C. H. Chang, “Small Signal Modeling and Control of ZVT-PWM Boost Converters,” IEEE Trans. on Power Electronics, Vol. 18, No. 1, pp. 2-10, 2003

[LiH00] Lin, J. L. and H. Y. Hsieh, “Dynamics Analysis and Controller Synthesis for Zero-Voltage-Transition PWM Power Converters,” IEEE Trans. on Power Electronics, Vol. 15, No. 2, pp. 205-214, 2000.

[LiH05] Lin, J. L. and Chun-Hsiao Hsia, “Dynamics and Control of ZCZVT Boost Converters,” IEEE Trans. on Circuits and Systems , Vol. 52, No. 9, pp. 1919-1927, 2005.

[LiL90] Lin, K. H. and F. C. Lee, “Zero-Voltage Switching Technique in DC/DC Converters,” IEEE Trans. on Power Electronics, Vol. 5, No. 3, pp. 293-304, 1990.

[LLH01] Lee, M. K., D. Y. Lee and D. S. Hyun, “New Zero-Current-Transition PWM DC/DC Converters without Current Stress,” IEEE PESC, pp. 1069-1074, 2001.

[LOL87] Liu, K. H., R. Oruganti and F. C. Lee, “Quasi-Resonant Converter: Topologies and Characteristics,” IEEE Trans. on Power Electronics, Vol. 2, No. 1, pp. 26-71, 1987.

[LYY04] Lin, J. L., S. P. Yang and C. H. Yu, “Averaged Modeling of A ZVT Soft Switching PFC Converter,” IEEE Asia-Pacific Conference on Circuits and Systems, Vol. 2, pp. 741-744, 2004.

[MaC91] Maksimoric, P. and S. Cuk, “Constant Frequency Control of Quasi-Resonant-Converter,” IEEE Trans. on Power Electronics, Vol. 6, No. 1, pp. 141-150, 1991.

[MaL97] Mao, H. and F. C. Lee, “Improved Zero-Current Transition Converters for High-Power Applications,” IEEE Trans. on Industry Applications, Vol. 33, No. 5, pp. 1220-1231, 1997.

[MHN03] Moisseev, S., S. Hamada and M. Nakaoka, “Double Two-Switch Forward Transformer Linked Soft-Switching PWM DC-DC Power Converters using IGBTs,” IEE Proceedings-Electric Power Applications, pp. 31-38, 2003.

[NTW95] Ned, M., M. U. Tore and P. R. William, Power Electronics, 2nd Ed., John Wiley, 1995.

[RLYH00] Ryu, S. H., D. T. Lee, S. B. Yoo and D. S. Hyun, “A Modified ZVZCS Commutation Cell for All Active Switches in PWM Converters,” IEEE PESC, pp. 760-765, 2000.

[SCFV01] Silva, E. S. D., E. A. A. Coelho, L. C. da Freitas, J. B. Vieira Jr and V. J. Farias, “A Soft Switched Forward Converter Without Current and Voltage Stress,” IEEE PESC, pp. 266-270, 2001.

[StH00] Stein, C. M. O. and H. L. Hey, “A True ZCZVT Commutation Cell for PWM Converters,” IEEE Trans. on Power Electronics, Vol. 15, No. 1, pp. 185-193, 2000.

[SuG92] Sun, J. and H. Grotstollen, “Averaged Modeling of Switching Power Converters: Reformulation and Theoretical Basis,” IEEE PESC, pp. 1162-1172, 1992.

[SuG93] Sun, J. and H. Grotstollen, “Averaged Modeling and Analysis of Resonant Converters,” IEEE PESC, pp. 707-713, 1993.

[TaL88] Tabisz, W. A. and F. C. Lee, “Zero-Voltage-Switching Multi-Resonant Technique: A Novel Approach to Improve Performance of High-Frequency Quasi-Resonant Converters,” IEEE PESC, pp. 9-17, 1988.

[WBC99] Wakabayashi, F. T., M. J. Bonato and C. A. Canesin, “A New Family of Zero-Current-Switching PWM Converter,” IEEE PESC, Vol. 1, pp. 451-456, 1999.

[WeI95] Wei, H. and A. Ioinovici, “DC-DC Zero-Voltage-Transition Converter with PWM Control and Low Stress on Switches,” IEEE APEC, pp. 523-529, 1995.

[XCL99] Xu, J., X. Cao, and Q. Luo, “An Improved Two-Transistor Forward Converters,” IEEE PEDS, pp. 225-228, 1999.

[YaL93] Yang, L. and C. Q. Lee, “Analysis and Design of Boost Zero-Voltage-Transition PWM Converter,” IEEE APEC, pp. 707-713, 1993.

[YLC06] Yang, S. P., J. L. Lin and S. J. Chen, “A Novel ZCZVT Forward Converter With Synchronous Rectification,” IEEE Trans. on Power Electronics, Vol. 21, No. 4, pp. 912-922, 2006.

[劉君上96]　劉君上，共振式DC-DC電源轉換器之分析與強健控制器之設計，碩士論文，國立成功大學工程科學系，1996。

[邱士峰97]　邱士峰，半共振式零電流切換型暨PWM電流回授型之DC-DC電源轉換器：製作分析及控制器之設計，碩士論文，國立成功大學工程科學系，1997。

[謝欣穎98]　謝欣穎，零電壓轉移柔性切換電源轉換器之動態模式分析及控制器之研製，碩士論文，國立成功大學工程科學系，1998。

[張景華99]　張景華，升壓型零電壓轉移柔切式電力轉換器之模式分析及控制器設計，碩士論文，國立成功大學工程科學系，1999。

[游志雄00]　游志雄，零電壓轉移高功率因數電力轉換器之模式分析及控制器設計，碩士論文，國立成功大學工程科學系，2000。

[夏存孝01]　夏存孝，零電流零電壓轉移柔切式升壓型電力轉換器之模式分析及控制器設計，碩士論文，國立成功大學工程科學系，2001。

[劉育伶02]　劉育伶，非浮接開關之零電流零電壓轉移柔切式升壓型電力轉換器之分析研製及控制器設計，碩士論文，國立成功大學工程科學系，2002。

[葉怡君03]　葉怡君，新型零電流零電壓轉移柔切式高功因AC/DC整流器，碩士論文，國立成功大學工程科學系，2003。

[賴建志04]　賴建志，具有同歩整流技術之零電流零電壓柔切轉移順向式DC/DC電力轉換器之研製，國立成功大學工程科學系，2004。

[唐碩甫04]　唐碩甫，零電壓柔性切換半橋式DC/DC電力轉換器之分析研製及控制器設計，國立成功大學工程科學系，2004。

[王秋豐05]　王秋豐，新型零電壓切換推挽式DC/DC電力轉換器之分析與研製，國立成功大學工程科學系，2005。

[葉淙益05]　葉淙益，具同步整流技術之倍流整流零電壓柔性切換非對稱半橋式DC/DC電力轉換器之分析與研製，國立成功大學工程科學系，2005。