Impact of Water Content on the Electrical Behavior of Epoxy Insulators

Polymers are widely used in indoor insulation. We analyze three epoxy samples with varying matrix and filler properties to determine the influence of water on their insulating properties. We observed a strong dependency of the leakage current and the sample temperature, under electrical stress, on the amount of absorbed water. Tri- hydrated alumina filler reduced the leakage current and temperature rise under electrical stress.