Life testing and screening of high voltage insulation systems for electrical-chemical compatibility

All aspects of a micaceous insulation system should be considered when determining its usefulness as a mechanical and dielectric barrier. The insulation must be suitable for application to the coil, impregnated with a resin to make the system void free (except for B-stage tape); must exhibit low tan Ii and high dielectric strength as well as good corona resistance; and must withstand the service conditions of coil insertion, vibration, thermal and moisture cycling. In this study we have been primarily concerned with the electrical-chemical compatibility aspects of systems evaluations.