單級高功因串聯諧振LED驅動電路之研製

LED具有體積小、壽命長、不易破碎、無汞污染及節能等特點，逐漸取代傳統的螢光燈成為室內照明的新式光源。一般市售的LED燈管驅動電路採用兩級或單級架構，其缺點為功率因數低及電路效率不高。本論文提出具有柔切功能之單級LED燈管驅動電路，整合具耦合電感之雙降昇壓轉換器與半橋式串聯諧振串接全橋整流之轉換器成為單級電路架構。將具耦合電感之雙降昇壓轉換器之電感設計操作在不連續模式下，可自然達到高功因與低輸入電流總諧波失真，且半橋式串聯諧振串接全橋整流轉換器具有柔切功能，可降低功率開關的切換損失來提高效率。本論文完成單級LED燈管驅動電路的動作原理分析及設計，藉此研製18W LED燈管的雛型驅動電路並量測其波形結果。最後，將實測結果與IsSpice軟體獲得的模擬波形進行比較，驗證了本論文提出之單級LED燈管驅動電路之實用性。

關鍵字

LED燈管；驅動電路；諧振轉換器

並列摘要

Due to features of smaller size, longer lifetime, harder to be broken, free of mercury and energy-saving, LED is going to replace the traditional fluorescent lamp as a new lighting source for indoor applications. The conventional LED lamp drivers are two-stage or single-stage topologies, and the disadvantages of them are limited power factor and circuit efficiency. Therefore, this thesis presents a single-stage LED lamp driver with soft-switching, which combines a dual buck-boost converter with a coupled inductor and a half-bridge series-resonant converter cascaded with a full-bridge rectifier into a single-stage power conversion topology. In addition, the inductor of the dual buck-boost converter with a coupled inductor is designed to be operated at discontinuous-conduction mode (DCM) in order to naturally obtain high power factor and low total harmonics distortion of input current (THD). Moreover, the half-bridge series-resonant converter cascaded with a full-bridge rectifier has soft-switching function to lower the switching losses resulting in high circuit efficiency. Besides, analysis and design of the proposed LED lamp driver are included in this thesis and a 18W-rated prototype LED lamp driver has been implemented and testified. Finally, experimental results are compared with the simulated ones obtained from the IsSpice software to verify the functionality of the presented LED lamp driver.