Partial Discharges at Artificial Defects in XLPE Cable Accessories under Superimposed Transients

Abstract

This paper investigates the triggering and development of partial discharges at artificial defects in the cross linked polyethylene (XLPE) insulated cable with accessories under superimposed voltage. The experiments are conducted on a 4-meter long 6/10 kV commercial XLPE cable sample, which is assembled with a cable joint and terminations. Defects are fabricated on purpose in the cable accessories. The cable sample was subjected to the superimposed voltage of 50 Hz AC with impulse voltage. Partial discharge activities are measured by a HFCT sensor and analyzed by PDflex. The measurement results show that, the impulse voltage could trigger partial discharges, which might be kept sustained by the AC voltage. The partial discharge activities are influenced by the AC voltage level, which is determined by the PDIV and PDEV.