AbstractsPhysics

LED lamps have become increasingly popular in the market thanks to high energy efficiency. Tubular LED lamps are widely adopted to replace conventional linear fluorescent lamps, like T8 and T12. Compared with rewiring of fixtures (remove or bypass the ballast) retrofit LED Tubes (TLED), which can be directly powered by the existing ballast, are preferred by installers. Today, T12 fluorescent tubes are still widely used in the US. A T12 electromagnetic (EM) ballast compatible retrofit TLED has great energy saving potential and commercial value. This work proposes a T12 EM ballast model and a compatible TLED driver. In this project, T12 EM ballast structure and classification were introduced. For compatible driver design, firstly a T12 EM ballast model was built in LTspice and its corresponding modeling approach was developed and verified. Different ballast measurement results were included in this report. The proposed TLED driver uses a buck-boost topology and self-oscillation control to achieve constant output power. By using emitter switch and proportional drive techniques, the proposed driver is compatible with various T12 EM ballasts, including single-lamp, dual-lamp and three-lamp ballasts. Experimental results from the prototypes demonstrated driver compatibility with the ballasts. The driver has a power efficiency above 85%. System measurements shown that power consumption of the retrofit TLED lighting fixture is 55% lower than its fluorescence counterpart. Advisors/Committee Members: Zhang, G.Q., Tao, H..