Extra low voltage DC grid LED lighting systems: photometric flicker analysis

The paper exposes the topic of LED lighting systems flicker. The topic of extra low voltage LED lamps flicker has not been much discussed yet. A variety of commercially available extra low voltage (ELV) lamps were tested with respect to the light flicker produced when powered by nominal DC voltage. The same measurement is repeated with distorted and fluctuating voltage. Reverse engineering methods were employed to reveal the link between the observed flicker level and the electronic ballast topology used in the lamps. The paper aims to formulate demands on DC LED lamp ballasts to avoid flickering.