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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.


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