返馳式發光二極體驅動器

Flyback Converter For Light Emitting Diode Driver Circuit

胡家傑(Chia-Chien Hu)

指導教授 ： 莊英俊

崑山科技大學/工程學院/電機工程研究所/碩士(2009年)

摘要

高功率白光二極體的高效率、驅動簡單、環保及壽命長的優點，吸引了大量工業界和學術界的注意力。高效率的白光LED極有可能取代白熾燈泡和螢光燈等傳統照明設備，並可應用在居住環境、工業及商業廣告方面。此項新的照明光源需要透過嚴密的調節LED的端電壓以及高功因才能實現。本文提出以返馳式電力轉換器來作為功因校正以及LED照明系統的應用。PI控制器為電壓迴路提供了充足和穩定的頻寬。此電力轉換器是用來控制電壓模式PWM和操作在不連續模式(DCM)，所以電感電流會隨著整流過後的電壓而改變並且產生高功因。對LED驅動迴路而言，設計一個flyback原型，去驅動18W LED燈，並且透過實驗測試來證明此理論。經由實測結果後，可得知LED整體照明系統之功率因數大於0.998以及總諧波失真小於6.0%。從實驗結果可看出整體系統的功能且能有效的應用在新的照明系統上。

關鍵字

發光二極體 ； 返馳式電力轉換器 ； 功率因數 ； 總諧波失真

並列摘要

High power white light emitting diode (LED) has attracted a lot of attention from both industry and academia for its high efficacy, simple to drive, environmentally friendly, and long lifespan. It becomes possible applications to replace the incandescent bulbs and fluorescent lamps in residential, industry and commercial lighting. The realization of this new lighting source requires both tight LED voltage regulation and high power factor as well. This thesis proposed a flyback converter for the LED lighting applications and input power factor correction. A PI controller has been inserted in the voltage loop providing sufficient bandwidth and stability margin. The converter is controlled with voltage mode PWM and run in discontinuous conduction mode (DCM) so that the inductor current follows the rectified input voltage, resulting in high power factor. A prototype topology of flyback converter for LED driver circuit is designed for an 18W LED lighting source is constructed and tested to verify the theoretical predictions. The measured performance of the LED lighting fixture can achieve a high power factor greater than 0.998 and a low total harmonic distortion less than 5.0%. Experimental results show the functionality of the overall system and prove it to be an effective solution for the new lighting applications.

並列關鍵字

light emitting diode ； flyback converter ； power factor ； total harmonic distortion

參考文獻

[22]林華偉，高功因隔離式SEPIC電力轉換器之分析與研製，碩士論文，崑山科技大學電機工程系，2008。

[23]陳建榮，以返馳式轉換器為基礎之高功因整流器研製，碩士論文，崑山科技大學電機工程系，2004。

[30]黃彥彰，單級高功因電力轉換器分析與研製，碩士論文，崑山科技大學電機工程系，2007。

[4]William R. Young, Jr. and William Wilson, “Efficient Electric Vehicle Lighting Using LEDs,” Southcon/96.

[6]R. H. Horng, D. S. Wuu, and S. C. Wei, “AlGaInP/AuBe/Glass Light-emitting Diodes Fabricated by Wafer Bonding Technology,” Appl. Phys. Lett. Vol. 75, pp. 154, 1999.