Study on mechanisms and propagation characteristics of partial discharges in SF6 GIS

It is imperative to study partial discharge behavior in SF6 GIS in order to carry out reliable insulation diagnosis and conditioning evaluation of practical gas-insulated systems. This paper deals with investigation on propagation characteristics of electromagnetic waves owing to partial discharges in a SF6 GIS model as well as the PD mechanisms, by utilizing various electrical measuring and optical detecting techniques. Leader discharges prior to breakdown can be readily discriminated and the attenuation characteristics of electromagnetic waves within the GIS has been established. A suggestion is also put forward to set up a comprehensive PD detection and insulation performance evaluation system for reliable and efficient application to practical GIS. (4 pages)