Title :
UHF detection of leader discharges in SF6
Author :
Sellars, A.G. ; Farish, O. ; Peterson, M.M.
Author_Institution :
Rolls Royce Ind. Power Group, Hebburn, UK
fDate :
2/1/1995 12:00:00 AM
Abstract :
The ultra-high frequency (UHF) technique of partial discharge detection has been used to study the partial discharges produced by electrode protrusions and surface contamination in a gas insulated substation (GIS). The paper describes the stages of discharge development from inception to breakdown. The work has shown that the UHF technique may be used to identify distinct phases of discharge activity corresponding to discharge inception and a prebreakdown condition. The prebreakdown activity is detected as an increase in the UHF signal magnitude which has been attributed to the formation of leader-type discharges. These discharges form an essential part of the breakdown process, and their detection can be used to identify when the system is close to breakdown. The paper describes a filtering technique that may be employed to optimize the sensitivity of UHF leader detection
Keywords :
SF6 insulation; UHF couplers; UHF detectors; UHF measurement; corona; gas insulated substations; partial discharges; SF6; UHF detection; UHF signal magnitude; discharge development; electrode protrusions; filtering technique; gas insulated substation; leader discharges; partial discharge detection; prebreakdown activity; prebreakdown condition; surface contamination; Electric breakdown; Electrodes; Filtering; Frequency; Gas insulation; Geographic Information Systems; Partial discharges; Substations; Surface contamination; Surface discharges;
Journal_Title :
Dielectrics and Electrical Insulation, IEEE Transactions on