Optimization of the electrical properties of epoxy-SiC composites for stress-grading application

Epoxy-SiC composites are commonly used as resistive field grading material for high voltage applications such as corona protection of the end-windings of the stator windings of large rotating machines. As a function of grain size, concentration and material composition, a wide range of electrical parameters can be reached for epoxy-SiC composites. In this paper, the optimized values of the electrical characteristics of the field-grading material (yielding the lowest maximum electrical field) were numerically calculated for a given geometry and it was found that these optimum values lay in the reachable range by SiC technology.