VHF PD detection of 110 kV XLPE cable accessories

Partial discharge (PD) can indicate defects in HV XLPE cable accessories. A new land of split-core PD sensor is designed that can be easy installed on-site and used safely, and has a bandwidth from 3 MHz to 60 MHz. A model of a cable accessory was made and some typical PD phenomena in this accessory were simulated, such as sliding discharge, floating discharge and cavity discharge. PD tests were made to find the features of the defects. The data from the tests were analyzed and the spectra of different types of PD were plotted using statistical parameters to reveal the feature of the different patterns of PD. The split-core PD sensor has been used on-site after sample testing in the laboratory. More than twenty cases of on-line PD detection for 110 kV XLPE cables have been obtained.