Development of partial discharge detection method using an autoregressive model in gas-insulated switchgears (GIS)

Gas-insulated switchgears are important equipment in electric-supply stations where advanced techniques for safety and maintenance are required. The paper focuses on the problems concerning the insulating functions of GIS to discuss a method of signal processing for partial discharge detection and position identification. An autoregressive model is designed for potential fluctuation in a state without any partial discharge. The difference was found between potential fluctuations measured during partial discharge and those of the normal state models. The index of whiteness test of the residual random process is a useful parameter for representing this difference. The use of this method allows partial discharge detection.