| Summary: | 博士 === 國立臺灣大學 === 電機工程學研究所 === 88 === This dissertation proposes three new single-switch electronic ballasts for fluorescent lamps, which are widely used in lighting. It includes the class E, series/parallel and charge pump derived electronic ballasts. In class E, low duty cycle operation with soft-switching reduces voltage stress of the main switch and a energy-storage capacitor is added to prevent flickers. The series/parallel converter is presented to reduce the voltage stress again and it also provides dimming control. The continuous-input-current charge-pump power factor correction reduces the input current ripple of the ballasts without complicated control. The presented ballast circuits are analyzed and the associated design equations are derived. Experimental waveforms and records also verify the theoretical derivation. Besides, design rules of the presented ballasts are given to facilitate practical applications. At last, comparing with the two-stage high power factor electronic ballast, the presented circuits have the same functions but use less active switches. They can reduce the ballast cost.
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