Identification of insulation defect by sequential measurement of partial discharge in GIS

Abstract

To maintain the insulation reliability on gas insulated switchgear (GIS), several partial discharge (PD) monitoring techniques have been utilized. To estimate the risk of a defect, it is important to identify the kind of defects and its condition. In this paper, every PD pulse of various defect types was sequentially measured by using high-speed PD measuring system. The sequential PD measurement was proved to be useful to identify the defect condition, because the temporal change of PD characteristics could show the accumulation of the space charge around the defect in GIS. © 2011 The Institute of Electrical Engineers of Japan.