抄録
This paper deals with the method of partial discharge (PD) detection with the sensor (antenna) put at the outside of the GIS tank. The flange of the spacer is paid attention as a leakage place of the UHF from the PD. Three kinds of antennas are proposed and made for trial purposes. And one commercial antenna is selected for this study. Comparative studies of the four antennas with the internal PD sensor (disk coupler) used worldwide so far are made from the viewpoint of the sensitivity characteristics. The difference between the sensitivity behavior of each antenna and the coupling mechanism with the electromagnetic radiation is discussed based on this result, and the sensitivity improvement plan of the antenna is considered. As a result, it has been concluded that making the feeding point of the antenna stick to the spacer flange contributes sensitivity improvement in a comparatively low bandwidth.
