An Investigation on the Dielectric Properties of Thermally-Aged Kapton and its Capability to Withstand Partial Discharges

摘要

The behavior of Kapton CR 200 was investigated as a function of time under thermal aging. Foils of Kapton were kept in the oven at 270 °C and extracted every 48 hours to test their electrical properties. The aim of the investigation was to understand the impact of thermal aging on the partial discharge inception voltage and Kapton’s endurance to partial discharge bombardment. The results highlight that after about 800 hours of aging the PDIV at 10 kHz decreases by 10%, whereas the other dielectric properties tend to show non-monotone behavior. The effect of thermal aging on PDIV seems to be a combined effect of a change in the Kapton permittivity and other factors that we were not fully able to highlight so far.