An analysis of harmonic diversity factors applied to LED lamps

On the reduction of the third-order harmonic losses in low–voltage power cables used for feeding large LED and CFL lighting loads

“…These results are different from those reported by other studies [12,17] where lower order harmonics did not exhibit a very large reduction in amplitude. However, it should be noted that in [12,17] random combinations of lamps were used.…”

“…As expected, the maximum attenuation of the third harmonic amplitude is achieved with harmonic ratios close to 1 and for harmonic phase angle differences close to 180 º. These results are different from those reported by other studies [12,17] where lower order harmonics did not exhibit a very large reduction in amplitude. However, it should be noted that in [12,17] random combinations of lamps were used.…”

“…In particular, diversity of topologies causes a diversity of phase angles and amplitudes of harmonic currents generated by these lamps. This leads to a lower vector sum than the arithmetical sum (which neglects phase angles) when different types of lamps are present, as described in [12,17].…”

“…Several other works have focused on the light distribution and visual performance of LED lamps (e.g., [16]), however, a relatively small amount of works focused on the harmonic emissions of LED and CFL lamps and in strategies to reduce the harmonic distortion problem generated by them [12,17].…”

“…A research on the diversity factor for combinations of LED lamps with powers in the range 3 to 8 W was presented in [17]. It was found that the diversity factor becomes smaller if a large number of lamps are combined.…”