A V-I slope-based method for flicker source detection

Flicker can be defined as the impression of unsteadiness of visual sensation induced by a light stimulus whose luminance or spectral distribution fluctuates with time. The flicker source detection is an important step in the power quality evaluation process as only after the information about the disturbance location is available, the diagnosis and troubleshooting can be accordingly carried out. This paper is concerned about the flicker source detection subject. The problem is described, the method is proposed and shown to be comprehensive enough to diagnose stationary and random flicker. Analytical proof, a simulation and a practical case assembled in laboratory are presented to show the validity of the method. Its principle is based in the relationship between voltage and current rms values, and it is possible to show that the behavior of this relationship permits one to draw conclusions about the flicker source.