About the Definition of PDIV and RPDIV in Designing Insulation Systems for Rotating Machines Controlled by Inverters

The partial discharge inception voltage (PDIV) and the repetitive partial discharge inception voltage (RPDIV) are key parameters for the characterization of the insulation system of rotating machines fed by power converters. In particular, these quantities have a fundamental role in the design and qualification of Type I insulation which has to last all life without partial discharges (PD). This paper analyzes the two definitions, taken from the IEC 60034-18-41 and IEC 60034-18-42 standards and shows potential discrepancies which can affect significantly insulation system design, especially going from two-level inverter to sinusoidal waveforms.