Partial discharge measurements for spherical cavities within solid dielectric materials under different stress and cavity conditions

The measurement of partial discharge is used in the performance assessment of insulation systems of high voltage components. This paper describes the development of a test object consisting of a single spherical cavity within a dielectric material. The test object is used to experimentally study the effect of variable applied frequency, applied voltage magnitude and size on PD activity. The obtained measurement data are analyzed and presented. The variations in the measurement results can be interpreted as changes in cavity parameters that can be used for PD modeling. The obtained data gives more information on how PD activity behaves under different stress conditions and the cavity conditions.