本文分析與設計單級高功因轉換器可調光發光二極體球泡燈電源電路，此電路為準諧振初級側調整架構，無需要二次側反饋電路，利用變壓器輔助繞組回授電壓至控制元件的偵測腳位，偵測開關汲源極電壓的波谷以達成波谷切換，減少切換損失。而在動態調光的部份，利用指令方式，將調光的資訊經過數位/類比轉換器轉換成類比訊號，傳送到脈衝寬度調變電路，改變輸出電流大小，產生調光效果。達成亮度5~100% 調光範圍，且在低調光範圍時發光二極體光源?定不閃爍，此電路具有高功因功能，元件的數量少、體積小，系統設計簡單優勢，不使用三端雙向可控矽開關元件調光，最後製作發光二極體球泡燈，驗證電路設計理論。 This thesis aims to research and propose a single-stage high power converter with dimmable LED driver.The circuit is a primary feedback control for the Quasi-Resonant without secondary feedback signal. With the auxiliary winding of the transformer , it feedbacks output voltage to the detecting pin of controlling component for detecting the switching drain-source voltage of the valley to achieve valley-switching and reduces the switching losses. For dynamic dimming ,with the instruction, the dimming information through digital / analog converter into an analog signal,can be transmitted to the pulse width modulation circuit, thereby changes the output current value ,to achieve 5~100% dimming and stabilizes the LED light source without flicker under low dimming condition.The circuit has the strengths with high power , few components, small size, simple design. The component of Triodes AC switch (TRIAC) is not required. To the end , the implementation of LED bulb has verified the feasibility of the designed circuit.
