Type of Supply Waveform, Partial Discharge Behavior and Life of Rotating Machine Insulation Systems

This paper highlights the effects voltage supply waveform can have on partial discharge, PD, characteristics in insulation systems of rotating machines fed by power electronics drives. While standards allow both sinusoidal and repetitive voltage impulse waveforms to be used for insulation design and type tests, the dependence of PD on the voltage waveform implies that the machine design and performance can be affected significantly by the waveform. Partial discharge inception voltage, partial discharge patterns and insulation life are, in fact, dependent on the type of test waveform. This can affect significantly the design of machine insulation system.