Changes of capacitance and dielectric dissipation factor of water-treed XLPE with voltage

Abstract

In this article, the changes of capacitance C and dielectric dissipation factor tan /spl delta/ of a non-penetrated water-treed XLPE sheet sample with voltage stress are discussed based upon the channel dynamism model. It has been found that the increase in tan /spl delta/ with high voltage stress is caused by the growth of the conductive water-filled channel layer. The gradual decrease in tan /spl delta/ with time of exposure to voltage stress is explained by a shift of relaxation frequency to higher range caused by the change in the conductivity of the water-filled channel layer.