Mechanical Behavior of Stator Endwindings

Electrically induced mechanical stress distribution in stator-end- windings insulation of a high-voltage rotating machine was investigated using an induction motor and model coils. Particularly the stress distribution generated in starting and restarting operations were measured. The magnetic flux around the end winding were computed and compared with its observed distribution. Difference between the two results were small, and then electromagnetic force around the end winding were calculated using this flux. Mechanical behavior of the end-winding insulation and change of its electrical properties due to the mechanical loading were measured.