Study of the online monitoring for GIS partial discharge based on UHF method

Ultra high frequency partial discharge detection method has advantages in interference immunity and detection sensitivity, and this paper aims to design online partial discharge monitoring system including ultra-high frequency sensors, data acquisition system and software system design for operating 126kV gas insulated switchgear. In the experiment, a chamber of 126kV GIS is selected as the solid model and the typical partial discharge source is also designed for study. The experimental result shows that the detection system can effectively avoid the space disturbance which is difficult to suppress by conventional methods of electrical measurement and other disturbances, and it accurately detects the partial discharge signal and identifies the type of discharge based on the signal spectrum. This paper also studies the influence factor of ultra high frequency signal measurement using the model and lays a basis for in-depth study of GIS partial discharge monitoring based on ultra high frequency method.