Autors: Rizov, P. M., Todorov, G. G.
Title: Assessment and analysis of the reliability of insulation system for high-voltage induction motors based on the partial discharge level
Keywords: Dissipation factor; High voltage induction motors; Insulation; Partial discharges; Residual life; Stator winding

Abstract: The object of the paper is an experimental study and analysis of the reliability of the stator winding insulation of high voltage induction motors that have been in continuous operation for more than 30 years. The analysis is based on experimental results of measurements of the dissipation factor values and partial discharges, performed on a number of induction motors in several consecutive years. They give an information to asses the current condition of the stator insulation, the trend of insulations deterioration and allow forecasting its residual life.


  1. Bartnikas, R. and R. Morin, “Analysis of multi-stress accelerated aged stator bars using a three phase test arrangement,” IEEE Transactions on Energy Conversion, vol. 21, pp. 162–171, 2006
  2. Zhu H., “Insulation resistance measurements versus temperature made on aged stator bars and coils” 2007 Electrical Insulation Conference, pp. 215–218, 2007
  3. Wilson, A., “Slot discharge damage in air cooled stator windings,” Proceedings of the Institution of Electrical Engineers, vol. 138A, no. 3, pp. 153–160, May 1991
  4. Bartnikas, R. and R. Morin, “Multi-stress aging of stator bars with electrical, thermal and mechanical stresses as simultaneous acceleration factors,” IEEE Transactions on Energy Conversion, vol. 19, pp. 702–714, 2004
  5. Soltani R., E. David and L. Lamarre, “Effects of humidity on charge and discharge current of large rotating machines bar insulation,” International Symposium on Electrical Insulation, pp. 412–415, Vancouver, 2009
  6. Stone, G. C., E. A. Boulter, I. Culbert, and H. Dhirani, Electrical Insulation for Rotating Machines—Design, Evaluation, Aging, Testing and Repair, 2nd Ed., Wiley—IEEE Press, 2014
  7. David E., L. Lamarre, “Low-Frequency Dielectric Response of Epoxy-Mica Insulated Generator Bars During Multi-Stress Aging”, IEEE Transactions on Dielectrics and Electrical Insulation, Vol. 14, pp. 212–226, 2007
  8. Bandyopadhyay M., S. Chattopadhyay, G. Roy, N. Mandal, S. C. Bera. “Dissipation Factor for High Voltage Electrical Machine,” IEEE Transactions on Instrumentation and Measurement PP(99):1-1 May 2019.
  9. Lamarre L., E. David, “Temperature Dependence of the Resistance of Modern Epoxy Mica Insulation of HV Rotating Machines,” IEEE Transactions on Dielectrics and Electrical Insulation, Vol. 15, pp 1305–1312, 2008
  10. Farahani, M., Borsi, H., Gockenbach, E. “Study of Capacitance and Dissipation Factor Tip-Up to Evaluate the Condition of Insulating Systems for High Voltage Rotating Machines”. Electrical Engineering Vol.89, 263–270, 2007
  11. Taesik Kong, Heedong Kim, Hungsok Park, Soohoh Lee, Joomin Park. “Changes in Insulation Characteristics of High-Voltage Motor Stator Windings with Temperature and Moisture”. American Journal of Electrical Power and Energy Systems. Vol. 7, No. 5, 2018, pp. 62-67
  12. IEEE Std 43-2013 - Recommended Practice for Testing Insulation Resistance of Rotating Machinery
  13. IEEE Std 56-2016 - Guide for Insulation Maintenance of Electric Machine
  14. IEEE Std 95-2002 - Recommended Practice for Insulation Testing of AC Electric Machinery (2300 V and Above) With High Direct Voltage
  15. IEEE Std 1434-2014 - Guide for the Measurement of Partial Discharges in AC Electric Machinery
  16. IEC 60034-27-1:2017 Rotating electrical machines – Part 27-1: Off-line partial discharge measurements on the stator winding insulation of rotating electrical machines


17th Conference on Electrical Machines, Drives and Power Systems, ELMA 2021, 2021, Bulgaria, DOI 978-166543582-6; 10.1109/ELMA52514.2021.9502982

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