隔離式順向電源轉換器之研製

Design and Implementation of ZCZVS Isolated Forward Converter

朱建忠(Jian-Jong Chu)

指導教授 ： 陳金鈴

崑山科技大學/工程學院/電機工程研究所/碩士(2006年)

https://doi.org/10.6828/KSU.2006.00071

摘要

傳統 PWM 轉換器，開關的切換屬於硬式切換，開關損耗大、雜訊、發熱嚴重，以致於無法朝高頻化與小型化發展。本電路為柔性切換之一次側箝位隔離式順向電源轉換器，採用兩個開關同時完成切換動作，可有效降低開關的電壓應力與電流應力。
盡量減少元件與附屬控制電路之使用，並省略零電流與零電壓檢知電路，僅以現有開關寄生電容、隔離變壓器磁化電感、漏感與外加共振電感構成共振槽路，使開關於共振點附近進行切換，減少切換損失及EMI干擾問題。於輸出整流器使用反應速度更快之二極體，配合一次側共振電感，即使輸出側未加入緩振器電路仍可有效減少整流二極體兩端的電壓突波。

關鍵字

二開關順向式電源轉換器 ； 一次側箝位隔離式 ； 零電壓零電流切換

並列摘要

For traditional PWM converters, the switch modeling of the power switch is hard switching which may cause great switching loss, noise interference, and serious heat generation. Therefore, it is impossible for such traditional converters to develop into high frequency and compact ones.
The primary-side clamping isolated forward converter adopts the soft switching model. It has two power switches to complete switching at the same time and to reduce voltage stress and current stress of the power switches fectively. The primary-side diode can be used as the restoration path for the magnetizing inductance energy of the transformer to enable the isolated transformer to complete reset before every duty cycle. The application of components and auxiliary control circuit should be reduced as much as possible, and the zero-current and zero-voltage diagnostic circuit are also omitted. The switching is conducted by using the parasitic capacity of the existing power switch, isolated transformer magnetizing inductance, leakage inductance and resonant induction only to form a tank circuit, allowing the power switches to be switched near the resonant point. In this way, the switching loss and EMI interference can be reduced. Using the diode with quicker reaction speed for the output rectifier plus the primary-side resonant inductance will decrease the voltage surge on both sides of the rectifier diode effectively even though there is no snubber circuit on the output side.

並列關鍵字

primary side clamping ； double switch forward ； forward converter ； ZCZVS

參考文獻

[1] K. H. Liu and F. C. Lee, “Zero-voltage switching technique in DC / DC converter,” IEEE Transactions on Power Electronics, vol.5, pp. 293-304, July 1990.

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[3] K. M. Smith Jr., and K. M. Smedley, “Lossless passive soft switching methods for inverters and amplifiers,” In Proc. Power Electronics Spec. Conf., pp. 1431-1439,1997.

[4] N. Mohan, T. M. Undeland and W. P. Robbins, “Power Electronics :Converters, Applications , and Design,” John Wiley &Sons, Inc., U.S.A.,1995

[5] K. H. Liu, R. Oruganti and F. C. Lee, “Resonant Switches: Topologies and Characteristics,” IEEE Transactions on Power Electronics Specialists Conference, pp. 106-116, July 1986.