The Effect of High Concentrations of MgO on Space Charge Accumulation and Electric Field Distribution in Epoxy Resin

Dielectric materials are an essential part of any electrical device. These materials are under constant development to optimize and improve their insulating properties and adjust them for specific applications. The recent trend of nanocomposites opens new possibilities for these materials via new kinds of modifications not possible in the past. Furthermore, with the increasing trend of HVDC applications, it is of rising importance to further study the effects of DC voltage stress on dielectric materials, as the phenomenon of space charge accumulation has a considerable impact on the longevity of the dielectric system. In this article, a cold-cure epoxy resin was used as a base material and MgO nanoparticles were incorporated in various weight percentages (0, 10, 20, and 30 wt.% of MgO) to create samples. The electric field distribution and space charge accumulation under a high voltage DC stress were measured via the pulse electro-acoustic (PEA) method.