Summary
The growing deployment of power electronic converters (PECs) introduces fast, non-sinusoidal voltage waveforms that can alter partial discharge (PD) behaviour and insulation life compared to under pure AC. The existing literature is limited but points out potential severe consequences by applying such complex waveforms to electrical insulation. For sharp electrodes on pressboard in mineral oil and PEC substrates, PD inception voltage (PDIV) is reduced with increasing voltage rise time (dv/dt). In mica‑epoxy insulation for rotating machines (Type II) a less clear correlation between PDIV and dv/dt is found. Long‑term degradation studies show that when PDIV is lower under switched voltages, the time‑to‑breakdown also decreases. When
Read more Read lessPDIV is similar for switched and sinusoidal voltages, time‑to‑breakdown is governed by the number of voltage cycles, the dv/dt is in that case less important. Organic non-PD resistant material, as typically used in Type I rotating machines, cannot survive long with PDs present and the PDIV is then a good measure on the insulation life.
Additional informations
| Publication type | Session Materials |
|---|---|
| Reference | D1_11884_2026 |
| Publication year | |
| Publisher | CIGRE |
| Country | Norway |
| Study committees | |
| File size | 1 MB |
| Price for non member | 30 € |
| Price for member | 30 € |
Authors
EBERG Espen - SINTEF Energi; LUNDGAARD Lars - SINTEF Energi; AAKRE Torstein Grav - SINTEF Energi; CAVALLINI Andrea - University of Bologna
Keywords
Partial discharge, power electronic converters, transformers, rotating machines, high voltage, insulation, breakdown, testing.
