Experimental study on the partial discharge characteristics of four typical defects in GIS

Partial discharge (PD) can be one of the most influential phenomena in the aging of electrical insulation systems. In order to ensure reliability in the operation of such equipment, the detection and interpretation of PD measurements is required to monitor the condition of insulation. In this paper, physical model of typical defects in gas-insulated substation (GIS) are established, and studied for PD using pulse current method, which are based on the characteristics of defects and PD checker instrument. The results show that the phase-resolved PD (PRPD) patterns, the time domain waveforms, average amplitude and central phase changing of PD signals have very similar distribution characteristics and those of different defect have different ones. So it would be very convenient for the recognition of PD types and a deeper study of the mechanism of PD.