Partial discharge patterns of magnet wire samples under voltage stresses

In many high voltage systems, partial discharges are an indication of insulation condition. The partial discharge test is a nondestructive method of identifying possible premature insulation breakdown. Magnet wires are used in various electrical equipments like injection coils, solenoids and small transformers. The aging process of the wire insulation was achieved through the application of high voltages, high temperature and high frequency. The tests were conducted for AWG 30 and AWG 31 twisted magnet wire samples. A high level of stress is present within several turns of coil windings. This paper is focused on the study of partial discharge patterns for magnet wire insulation. The partial discharge inception voltages (PDIV) are measured for different twisted wire samples. An evaluation of the parameters charge intensity, pulse count, and pulse phase position are presented in 2- and 3-dimensional plots.