LED燈具有包括長達100,000小時以上的操作壽命、寬廣的工作溫度範圍以及無汞汙染等優點,因此非常適合應用於各種照明場合。單級返馳式功率因數修正轉換器廣泛使用於LED燈驅動器,其簡單的單級電路架構可同時達成功率因數修正以及LED電流調整。然而,由於高元件應力的限制,所以很難在寬廣輸入電壓變化下滿足高功率因數的要求。本論文提出一種具有廣域輸入電壓特性之單級LED燈驅動器,詳細分析與討論了所提出LED燈驅動器之工作原理與設計考量。一部雛型電路被實現與測試,能夠在寬廣輸入電壓變化下,達到高效率、高功率因數及調光控制的要求。
LED lamps have numerous advantages such as up to 100,000 hours of operative life, a wide range of operation temperature, and no mercury pollution such that they are very suitable for various lighting applications. A single-stage Flyback PFC converter is commonly used for LED lamp driver. Power factor correction and LED current regulation can be achieved with a simple single-stage circuit topology. However, the requirement of high power factor is difficult to be satisfied under wide input voltage variations due to high component stresses. In this thesis, a single-stage LED lamp driver with universal input voltage feature is proposed. The operating principles and design considerations for the proposed LED lamp driver are analyzed and discussed in detail. A laboratory prototype has been built and tested. With the prototype, high efficiency, a high power factor, and dimming control can be achieved under wide input voltage variations.