文探討應用在多燈管多安定器系統上之被動式管電流均流技術及主動式管電流均流技術。而本文所探討多燈管多安定器系統之產品是以液晶顯示器之背光模組為對象。目前此背光模組所提供的光源主要是由冷陰極螢光燈管來提供，隨著顯示器螢幕尺寸增加，此模組所需要的燈管數量、燈管長度和安定器數量亦隨之增加；因為燈管彼此間組抗特性之差異，以及安定器彼此間特性之差異會造成燈管間之亮度不相等，進而會造成人視覺上之不適。為了解決此一問題，管電流之均流技術被提出。

　　目前，主要的管電流均流技術是以被動式管電流均流技術為主，但此一技術存在著：(1)更多的元件，造成成本的增加；(2)被動均流網路之元件參數設計不易；(3)在頻率的變動下，失去均流的效果；(4)當發生故障時，特定元件要承受高電壓應力，產品之維運成本提高。為達到均流之目的以及改善被動式管電流均流技術之缺點，本文提出一主動式管電流均流控制電路架構。
　　
　　本文實作一組使用此主動式管電流均流控制電路架構的三個安定器三燈管之冷陰極螢光燈驅動電路。此一驅動電路在調光中良好的均流能力在實驗結果中得到驗證。

　　This thesis presents passive and active current-equalization techniques for equalizing the lamp currents of multi-lamp electronic ballasts. Multi-lamp products, such as the backlighting for liquid crystal display (LCD) panels, must be capable of equalizing luminance. Due to the deviations of lamps and ballasts, the currents flowing through the lamps are not equal, which causes poor-quality backlight sources for LCD panels. This leads to discomfort for human eyes. Additionally, since the size of thin-film transistor LCD (TFT-LCD) monitors is becoming larger, a multi-lamp drive system must provide higher levels of voltage and current and more power for longer length lamps and more lamps. Since the number of lamps that can be driven by one inverter is limited, distributed multi-ballast drive systems are becoming popular.

　　In order to solve the problems of current equalization and difficult control for distributed multi-ballast drive systems, the active current-equalization technique is proposed to equalize every output current of the ballast, and the passive current-equalization technique is used for each individual multi-lamp system of the ballast to equalize currents through the lamps.

　　In this thesis, the three-ballast drive system, for distributed single-lamp inverters, is implemented with the active current-equalization technique. In addition, dimming range and current-equalizing ability are demonstrated by experiments in order to verify the performance of the proposed active current-equalization circuit scheme.

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