Partial discharge trends in medium voltage cables measured while in-service with PDOL

This paper presents partial discharge trends of various developing faults such as drying out of impregnated paper cables, moisture ingress, earth screen damage, etc. These trends were measured over either weeks, or months, by PD-OL (PD Online with Location), which measures and locates PD activity. The presented cases are results from continuous measurements on more than 150 cable connections.