Influence of epoxy system formulation on partial discharge behavior of resin impregnated coils

This paper discusses the influence of filler characteristics on the rheological behavior of different epoxy based casting resins. Low filler contents and large grain sizes result in low viscous resins. However, for improving electrical properties, such as partial discharge behavior of large-scale coils, impregnation, fracture toughness and viscosity of the epoxy system must be optimized. Out of the investigated three epoxy resins, only the one with good impregnation properties showed satisfying partial discharge behavior of the final product.