Effect of vacuum pressure impregnation process on electrical conductivity of conductive armor tape having various tape builds and constructions

Measurements of the electrical conductivity of conductive armor tape (CAT) applied to medium and high voltage motor form wound coils, having various tape builds and constructions, show conductivities that differ significantly after vacuum pressure impregnation (VPI). Tape builds consisting of a single half-lapped layer and a double half-lapped layer are studied at 30 and 100 °C. Electrical conductivity in both surface and transverse directions show significant difference before and after VPI. This demonstrates the importance of using measured conductivity after VPI for simulation studies. Simulations for pulsed voltage with 1 µs rise time show that higher CAT conductivity increases the electric field in the stress grading tape layer.