6th International Young Scientist Congress (IYSC-2021) and workshop on Intellectual Property Rights on 8th and 9th May 2021.  10th International Science Congress (ISC-2020) will be Postponed to 8th and 9th December 2021 Due to COVID-19.  International E-publication: Publish Projects, Dissertation, Theses, Books, Souvenir, Conference Proceeding with ISBN.  International E-Bulletin: Information/News regarding: Academics and Research

Important aspects of Inter turn Insulation in High Voltage Motors

Author Affiliations

  • 1 Singhania University, Pacheri Bari, Rajsthan, INDIA

Res. J. Engineering Sci., Volume 2, Issue (5), Pages 15-18, May,26 (2013)


High voltage induction motors play a vital role in reliable operation and performance of process industries and utilities of power plants. H.V. motors are used to drive boiler feed pumps, primary air fan, cooling water pumps, induced and forced draught fan drive motors, mill motors and other utility operation in thermal power plant. Induction motors have been the most popular electric motors in the family of motors. The failure data on large induction motors indicate that the stator related failure account for about 37% of the total failure. Stator insulation failure results from either the failure of turn to ground insulation or turn to turn insulation which ultimately leads to main insulation failure. The inter turn insulation in a motor is a weak spot, soundness of inter turn insulation is crucial for reliability of motor. The present paper is aimed to identify the occurrence of inter turn faults within the coils and turns of the stator winding, requirement of inter turn insulation details of inter turn insulation systems and impulse voltage withstand capacity of inter turn insulation., precautions to be taken during manufacture and assembly of winding.


  1. Popescu Mirecea, Induction motor modeling for vector control purpose. Helsinki University of technology Espoo (2000)
  2. Valery Vodovozov, Introduction to power electronics, Ventus Publishing (2010)
  3. Lecture notes on Switching over voltages in H.T. Motors Programme on Influence of switching transients on stator insulation for BHEL engineers (1999)
  4. Stone G., Boulter E.A., Gilbert I. and Dhirani H., Electrical Insulation for Rotating Machines, Wiley/IEEE Press (2004)
  5. Oyegoke B.S., Transient Voltage Distribution in Stator Winding of Electrical Machine Fed from a Frequency Converter". Acta Polytechnica Scandinavica, Electrical Engineering Series, 100, (1999)
  6. Hamid A. Toliyat, Gerald B. Kliman, Hand book of electrical motors, CRC press (2010)
  7. Lanham Curtis Understanding tests that are recommended for electric motor predictive maintenance Baker instrument company (2010)
  8. Investigation report of 10 MW BFP stator coil BHEL (2004)
  9. Puranik K.K., Switching Surges in H.V. Motors and Importance of Inter turn insulation 6th International Conference on Electrical Rotating Machines (2004)
  10. Rudolf Brütsch and Dominique Rey Conductor insulation for rotating machines 10th INSUCON International Electrical Insulation Conference, Birmingham, UK, 24-26, (2006)
  11. Puranik K.K., Salient aspects of inter turn insulation of high voltage motors, International seminar on electrical and electronic insulation (1993)
  12. Wilson John Surge Voltage Distribution in Form Wound Motor Windings Baker instrument company (2005)
  13. Humiston T. and Pillay Pragasan Measurement of surge propogation in induction machines IEEE Transaction (2003)
  14. Impulse voltage withstand levels of form-wound stator coils for rotating a.c. machines IEC 60034 Part 15, Edition 3.0 2009-3 (2009)