In this paper, a rectified quasi-sinusoidal pulse width modulation (RQSPWM) controller is first proposed for the cold-cathode fluorescent lamp (CCFL) ballast to achieve a synchronous primary-side dimming control. It is seen that, with the novel controller, not only the lamp flickering problem and the thermometer effect can be eliminated but also the useful photo-coupler in secondary side can be avoided to reduce cost. Then, small signal models of the CCFL ballast and the proposed RQSPWM dimming controller are derived to analyze the performance of the ballast system and help corroborate hardware loop measurements. Finally, a prototype is constructed for verifying the effectiveness of the proposed closed-loop dimming control strategy
"A SYNCHRONOUS PRIMARY-SIDE DIMMING CONTROLLER FOR COLD-CATHODE FLUORESCENT LAMP BALLAST,"
Journal of Marine Science and Technology: Vol. 13
, Article 5.
Available at: https://jmstt.ntou.edu.tw/journal/vol13/iss2/5