Partial discharge activity in presence of pulsed waveforms

Partial discharge (PD) measurements can be a very powerful tool for the condition assessment of electrical insulation systems. When applied to rotating machines or winding insulation mock-ups, if pulsed power supplies are considered (PWM), PD measurement can provide not only an "on/off output about the presence or not of PD pulses but could also provide information about the degradation processes. In this paper the outcome of digital PD acquisitions, performed applying both sinusoidal and pulsed voltage waveform, is proposed, evidencing how the PD activity and the relevant PD patterns can be affected by the voltage waveform and by the voltage amplitude.