Study of partial discharge localization methods for EHV prefabricated joint

With an example of PD localization for EHV cable joint on site, multiple method of PD localization is studied in this paper, including (1) method of using metallic foil electrode sensors, (2) method of excitation by X-ray radiation and a foil electrode sensor, and (3) method of applying acoustic emission sensors and a foil electrode sensor. Compared with the conventional method of PD localization for long distance cables of more than hundreds of meters, it is more difficult to localize a PD for a pre-fabricated type of joint of only a short length of around 2 m, due to problems in measurement such as the disturbance of pulse reflection, the complicated route of pulse propagation and the difference of pulse propagation velocity. The results of the example also show that this multiple method can give a high accuracy of PD localization.