Application of newly developed Epoxy-Anhydride VPI resin for high voltage motors and generators

Epoxy-Anhydride VPI resin generally has excellent electrical insulation properties, mechanical properties and much lower curing volatile than other types of VPI resins, such as Epoxy Ester-Styrene system and Unsaturated Polyesterimide-Vinyltoluene system. So it is widely used in insulation applications of electrical apparatus. In this paper, a toughness modified epoxy-anhydride VPI resin was developed, and partial evaluation results of the newly developed Epoxy-Anhydride VPI resin on coils for high voltage (HV) motors are reported. The mechanical properties are tested and compared with commercial epoxy-anhydride resin. The electrical insulation properties including dielectric loss, breakdown voltage, partial discharge, electrical aging life etc. of 13.8kV coils for HV motors are studied and compared with the Unsaturated Polyesterimide-Vinyltoluene and commercial epoxy-anhydride VPI resin systems. The results indicate that HV coils treated with this Epoxy-Anhydride VPI resin are of superior insulation properties.