Constant power control based self-oscillating electronic ballast

This paper presents the constant-power control circuit, which maintains the input power and lamp power of the self-oscillating ballast. Abilities of constant input power and lamp power are required for the self-oscillating ballast. The conventional self-oscillating electronic ballast is disadvantageous because the input power and lamp power vary according to the input voltage. This difference in lamp power causes poor quality of illumination for the lamp. In order to solve the problems of the self-oscillating electronic ballast, a constant-power control circuit is proposed to provide constant input power and lamp power. In this paper, a 38 W self-oscillating ballast with the constant-control circuit is implemented. The ability to provide constant levels of input power and lamp power is demonstrated in the experimental results to verify the performance of the proposed constant-power control circuit.