Characterizing insulation systems of rotating machines controlled by power electronics: The role of partial discharges

The effect on adjustable speed drives on the life of rotating machines can be dramatic, causing premature failure even after short operation time. Significant amount of research has been devoted to this topic which may have a huge impact on reliability, maintenance and cost of various types of assets, from industrial plants to renewables, from transportation to oil and gas. Standards have been issues or are being issues to provide acceptance, type and diagnostic tests. This paper wants to summarize and discuss the problem inherent to the negative influence of power electronic supply on rotating machine reliability, and the relevant work made under IEC for the characterization and testing of the so-called Type I and Type II insulation systems.