Relation between the trend of partial discharges and aging models under AC voltage

The research work reported in this paper has the aim to contribute in the development of a new physical aging model for damage inception and growth from micro-cavities in polymeric insulating materials subjected to partial discharges (PD) under AC voltage. Aging tests were performed on polyethylene (PE) layered specimens with cylindrical microcavities. The PD activity taking place inside the micro-cavities was monitored during the aging process. PD patterns, discharge repetition rates and discharge amplitudes were recorded. Common features can be extracted in the changing trend of PD repetition rate and discharge amplitude. Furthermore, damage growth rate, as well as degradation severity, are inferred through simple statistics.