Electrical characterization of vegetation contacts with distribution conductors - investigation of progressive fault behavior

Vegetation intrusion is a major cause of faults, outages, interruptions and other power quality problems on electric distribution feeders. Despite the problem vegetation intrusion presents, little fundamental work exists regarding the characterization of electrical signals generated from vegetation contacts. This paper discusses efforts to further characterize the physical and electrical phenomena associated with vegetation contacts on distribution feeder conductors through field experiments. Researchers used tree branches of varying types and diameters to span primary phase and neutral conductors while recording feeder currents and voltages at a remote substation. Video and still photographs detailing the physical progression of vegetation- related faults were also obtained. The results discussed in this paper enhance the understanding of the electrical and physical progression of vegetation-related events, and suggest the continued use of measured electrical signals for detection of incipient vegetation conditions.