Breakdown of solid insulating materials under high frequency high voltage stress

This paper presents the variation of breakdown voltages experimentally obtained under high frequency high voltage stress on different insulating materials viz., PTFE, polypropylene and paper. An experimental facility using a vacuum tube oscillator circuit has been developed for the generation of high frequency high voltages. The breakdown voltages at high frequencies are found to be much lower than the breakdown voltages at 50 Hz. The cause for lower breakdown voltages could be due to the increased internal heating as well as the intense partial discharge activity taking place within the material