Analysis of partial discharge Ultrasonic wave characteristic on typical Defects in GIS

For analyzing partial discharge ultrasonic wave characteristic on typical defects in SF6 gas insulation switchgear (GIS), a 110 kV GIS was taken as an object to design and simulate the typical partial discharge models in GIS. There are point electrode model on bus and cavity of GIS, floating electrode model, air interstice model in insulator, metal particle and iron core electromagnetic shock models. PD signals on different defects were thus detected with the ultrasonic method. The experimental results indicated that the ultrasonic signals of different defects showed different characteristics in waveform, amplitude and phase resolved partial discharge chart, which is helpful in PD pattern recognition for GIS.