On-site partial discharge measurements on premoulded cross-bondingjoints of 170 kV XLPE and EPR cables

摘要

A total number of 15 premoulded joints of three 170 kV cablencircuits (XLPE and EPR) were equipped with partial discharge (PD)nsensors. The developed sensors are based on inductive high frequencyncoupling of partial discharge pulses occurring in the joints. The PDnactivity of each joint was monitored during an after laying ACnacceptance test. The test voltage of 190 kV was generated by means of anfrequency-tuned series-resonance test set. The signals of the PD sensorsnwere assessed with a spectrum analyser in a frequency range from 15 ton50 MHz, allowing a good separation of noise from PD signals under highninterference levels. The investigation demonstrated the feasibility ofnon-site PD measurements on joints during after laying tests