Serious problem happening in squirrel cage induction motor
Rating :- 900 kW_6P_6.6kV
Type of cooling :- CACA
Problem : Noise (very high - touched 100 db) and vibration (upto 20 mm/second)
Description of problem : It is not clear whether it is mechanical or electrical noise.As soon as the motor runs on no load ,vibration and noise increases with speed.
Slot combinations used are 54-Stator & 70-Rotor.
Problems found : 1. Air gap eccentricity is violated 2. Waviness of body.
I would like to know what the motor is going through electrically & mechanically and solutions to it will be highly appreciated.