Partial Discharge Detection in an Aeronautical Power Cable

The augmentation of voltage levels in aeronautical power networks may provoke the phenomena of electrical discharges. It is shown that PDs occurred at the cable periphery in proximity to a grounded conductor for voltages ranging from 750 V to 2000 V for gas pressure from 100 mbar up to atmospheric pressure. At higher voltage, internal PDs were found to take place between the conductor strands and the inner walls of the cable insulation. This discharge localization was confirmed by the dependence of PDIV and RPDIV values on the imposed gas pressure and by electrostatic calculations taking into account the gas breakdown voltages from the Paschen curve. The influence of thermal aging on PD activity was also investigated. Thermal aging was found to not change the external discharge inception voltage but to affect internal discharges.