R.B. Timens

Experimental characterization of CFL bulbs for power quality assessment

This paper presents the results of a systematic set of voltage and current transient measurements aimed at characterizing the electrical behavior of a typical energy efficient compact fluorescent light bulb. The considered device represents a well-known example of a number of nonlinear loads that are now massively used in any house or office building and that are contributing to the degradation of the power quality due to highly distorted current absorptions. The comparison between measured data and the predictions obtained by means of a simplified SPICE equivalent of the device under test concludes the work.

Analysis of current transients caused by voltage notches

An analysis of current transients caused by voltage notches in an industrial plant is presented in the paper. The source of current transients in the factory lighting was traced to the operation of the nearby six-pulse AC/DC converter. Because of the short duration of the phenomenon, it was not possible to determine if there is a parallel resonance using a standard power quality analyzer. To determine the nature of the interaction, a measurement was done with a storage oscilloscope, and advanced signal processing was applied to the results. Using this technique, it was possible to exclude the presence of a parallel resonance. It was concluded that the transients are a reaction of lamps to voltage notches in certain working regimes of the six-pulse converter. Possible solutions to the problem are separating the supplies of the converter and the lighting installation, filtering, or adding additional line reactances.