Design and Implementation of Electronic Ballast for Fluorescent Lamps with Low Lighting Flicker

This paper proposes an electronic ballast circuit for fluorescent lamps with low lighting flicker. The electronic ballast with constant-frequency control, in which the DC-bus voltage is fed by a power-factor corrector, has a low-frequency ripple, which can cause lighting flickers in fluorescent lamps. Precise image-detecting systems require lighting sources (such as fluorescent lamps) with low levels of lighting flicker. The presented ballast operates by detecting the DC-bus voltage ripple as a feed-forward signal in order to modulate the switching frequency of the inverter. Thus, the voltage gain of the resonant tank is adjustable. As a result, the lighting flicker caused by the DC-bus voltage ripple can be decreased. Finally, the experimental and simulation results are in agreement, so the functionality of the proposed circuit is verified