Ageing kinetics of solid insulating materials submitted to partialdischarges

摘要

An attempt is made to correlate the characteristics of thenelectrical signals due to partial discharges (PDs) with the ageingnkinetics of the insulating material subjected to these discharges. Thenlight emitted by a single PD and the corresponding electrical pulsesnhave been recorded using a high-speed camera and a computerized signalnacquisition system. The discharge development both in time and space isnrelated to the electrical pulse shape, i.e., the amplitude of eachnfrequency component of the electrical signal, and can be related to thenageing of the insulating material. Several steps of insulation ageingnappear. The surface wettability and thus surface conductivity increasenat the very beginning of exposure to PD