Impulse and DC breakdown strength of polypropylene thin film

The paper presents the results of a study of the electric strength of a polypropylene film with a thickness of 2 μm. The breakdown voltage of the film was determined under the influence of electric pulses and with a slowly increasing voltage. The rate of increase in voltage at the pulse front varied from 1.8 to 78 GV/s, and with a slowly increasing voltage it varied from 28 to 1100 V/s. A statistical analysis of the breakdown voltage data was performed. For both modes of electrical testing and at all rates of voltage increase, the most probable breakdown voltages Fbr.exp were calculated. The effect of the voltage rise rate on the value of Fbr.exp was not detected. The obtained values Fbr.exp were approximately the same for both test modes and amounted to 550 MV/m for DC and 570 MV/m for pulses