[[alternative]]Design and Implementation of Electronic Ballast for Automotive Xenon Headlight Lamp

碩士電機工程學系[[abstract]]本文主要在於研製以直流12伏特電源為主的汽車用氙氣頭燈電子式安定器，電子式安定器使用高頻DC-DC轉換器(Converter)以及DC-AC反流器(Inverter)所組成的架構來改善傳統電磁式安定器的體積過大、效率低、燈光穩定性欠佳與燈管壽命短的問題。氙氣燈使用低頻的交流方波電流驅動可以改善音頻共振的問題。目前常用的氙氣燈電子式安定器多半以全橋式反流器為主，但這種架構的成本較高。使用傳統半橋式反流器成本較低，但此方式可能使負載無法在低頻順利工作，且會有不平衡的電壓輸出及中性點偏移(暫態變化時)的現象。本文提出前級使用返馳式DC-DC轉換器產生兩組相同的直流電源，供給後級半橋式反流器所需直流鏈電壓，最後再經由此半橋式反流器將直流鏈電壓轉換成為能夠改善燈泡壽命、燈光穩定性及發光效率的低頻方波交流電壓，此種架構可以改善傳統半橋式反流器的問題，並且具有比全橋架構成本低的優點。本文最後以實驗測得的結果來驗證雛型電路之可行性，並且提出實驗過程中所觀察的現象及心得，提供未來研究者所需要的參考資料。[[abstract]]Abstract The goal of the thesis is to design and implement an electronic ballast for automotive xenon headlight lamps using DC 12V battery power source. Compared with electromagnetic ballasts, the electronic ballast used in this study utilizes the technology of switching converter and inverter to improve the efficiency, device size, lighting stability and lamp lifetime. Furthermore, the acoustic resonance problem can be solved by supplying square-waveform alternative current to the lamp. Typical electronic ballasts use a full bridge inverter to drive the xenon lamp, but this method increases the cost significantly. On the contrast, the traditional half bridge inverter has the advantage of lower cost but three intrinsic disadvantages: (1) unbalanced voltage output; (2) DC offset in transient period; (3) possible power failure at low operation frequencies. In order to solve these three problems, this study applies two DC power sources generated from a flyback converter for the half bridge inverter. The experimental results prove the feasibility of this method and show fine performance. In addition, several suggestions for advance research on the electronic ballast are presented in the thesis