Twisted pair specimens insulated by conventional and nanocomposite enamel: Life curves and PD patterns

This work concerns the comparison between the behaviour of winding wires insulated by a conventional organic enamel or by a nanocomposite enamel, when subjected to the action of surface partial discharges. Some aging tests were carried out applying a 1500 Hz sinusoidal voltage with different amplitudes. The outcome was summarized through lifetime plots. During the tests, partial discharges (PD) patterns were also acquired. Analyzing the lifetime curves and the PD patterns obtained from the monitored PD activity, it was possible to point out some interesting features and new factors that allowed to arrive at a correct comparison between the two different insulating systems involved.