Frequency acceleration of surface partial discharge tests on thin polymer films

An experimental investigation about the validity of applying frequency acceleration to recently devised testing procedures, aimed at evaluating the endurance to surface partial discharges of thin polymer films, is presented. The results of tests performed from 50 Hz up to 1000 Hz, on three different polymer films indicate, that no constant acceleration factor can be assumed, even for same material with different thicknesses. Therefore it appears that a correct comparison of different thin polymer films surface partial discharges endurance, in general and especially when using the presently adopted testing procedure, should be made on the grounds of results of tests performed at the service frequency. Nevertheless frequency accelerated tests could be useful to compare same films (polymer and thickness), as in the case of quality control procedures, in a relatively short time