Voltage flicker from warm and cool white LED bulbs

Flicker is a major concern in low power LED bulbs in present days. Flicker is usually associated with design of driver but it also includes external factors like load, grid system, dimming, etc. Conventional light sources like incandescent lamps modulate light output, but the severity of flicker effects in LED and its impact on human health and productivity is taken lightly. In general, the cool white LED bulbs are majorly used in residential, industrial and commercial purposes, so more number of people is exposed to their daily activity to flicker. This paper shows the voltage flicker indices of warm white and cool white LEDs which are of low power. From the experimental analysis, it is found that the cool white LEDs show more flicker than warm white LEDs by about 50% higher than the limits for safe usage as per IS 14700-3-3: 2018 standard. Also if the Pst values are made equal to Plt values while designing the drivers, then flicker effects can be reduced effectively.