A comparison of the electrical performance of various turn and strand insulation systems before and after rapid thermal cycling

IEEE is considering developing a guide for evaluating turn and strand insulation in multi-turn form wound coils for medium and high voltage coils up to 15KV. It is hoped that this guide will prove useful in comparing different systems based on the degradation of the surge breakdown voltage of coils subjected to a series of rapid thermal cycles. This paper is an attempt to compare, process and performance aspects of three separate turn insulation systems - Polyester Glass over enamel, PET Mica strand insulation, and a dedicated Glass Mica turn insulation over enamel strand insulation.