Analysis of Residual Stress at the Curing Interface of Epoxy Resin Impregnated Paper for Dry-Type Bushing

The interfacial residual stress formed in the preparation of dry-type bushing is an important factor restricting its reliable operation. In this paper, the kinetic equation of epoxy resin impregnated paper curing is derived by using the non-isothermal DSC analysis method, and the dry-type bushing model is established by simulation software to derive the temperature, curing degree change, and interfacial residual stress distribution of dry-type bushing in the curing process. According to the results, the maximum value of the interface residual stress formed after curing occurs at the contact between the impregnated paper and the ends of the center capacitor, which is up to 10.9 Mpa. This result will be conducive to the efficient manufacturing and reliable operation of the dry-type bushing.