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Breakdown voltage of polypropylene film during C and thermal ageing

This paper investigates the electrical breakdown of biaxially oriented polypropylene (BOPP) film during accelerated DC and thermal ageing. The DC breakdown voltage of 6.5 μm thick capacitor grade polypropylene (PP) films was measured. Two types of films with different crystallinity were tested. 88 breakdowns per sample were collected. The scale and shape parameter of the Weibull distribution were fitted to the data. The scale parameter values obtained vary between 713 and 804 V. Results indicate that during ageing procedure the film crystallinity is an influencing factor of their breakdown voltages.