Date of Award


Degree Type



Electrical Engineering

First Advisor

Stankovic, Ana

Subject Headings

Rotary converters, Ballasts (Electricity)


The contribution of this thesis is the analysis of a Synchronous Buck converter, used as the second stage (which controls the current through the lamp, and consequently, the lamp power) in a 3-stage High-Intensity Discharge (HID) ballast. Where previously standard Buck converters were used, this new application of the Synchronous Buck converter to a medium-power lighting ballast improves efficiency by operating the converter in a new, modified critical-conduction mode to achieve soft-switching and improve efficiency significantly. The converter and 2-loop controller will be analyzed in the three HID lamp modes of operation: open circuit, short circuit, and power control mode. Simulation and analytical results are compared to the experimental results.