Stator End-Winding Vibration in Two-Pole Machines: Avoiding Generator Failure

In the past 15 years, insurance industry data have indicated that stator end-winding vibration has become the most important cause of generator failure. The source of vibration is the current creating magnetic forces between coils, and it may be amplified due to mechanical resonance. End-winding vibration leads to failure by insulation abrasion or copper fatigue cracking. The extent of the repair caused by the ensuing damage and the loss of production have proven to be very costly.