Frequency and Waveform Effects on the Turn Insulation Life Time
Published reports on the reliability of the drive fed induction machines indicate that the most significant defects in the induction motors comprise of weakness and deterioration in the insulation systems. Therefore researches have been dedicating more focus on the improvement of the insulation performance of the drive fed induction motors in the last five past decades. New generation of high- frequency switching power electronic devices, lead to a major challenge in utilizing inverters in both of the starting the electrical motors and controlling of them. The drives output consists of high frequency and high amplitude impulses with a short rise time and a different pulse widths. Therefore, assessment of impulse shape effects with different frequency on the stator winding could be worthwhile. In this research, sinusoidal and impulse waveforms with the fast rise time will be applied on the samples and found out more by comparing their effects on the partial discharge behaviour. Moreover, effects of waveform frequency will be deeply assessed. Additionally, partial discharge density will completely analyse not only electrically, but also optically. At the end, the effect of waveform on the lifetime of the turn insulation will be studied. The results could be potentially a proper reference to give researcher to deepen their understanding about the responses of turn insulation in various working condition of drive fed induction motors.