(369f) Numerical Simulation to Predict Motor Bearing Damage By Electrical Pulses
The simulation model is developed based on the gap between the bearing ball and the race. Since the grease used between the gap has a partial insulating effect, charge accumulates on the rotor assembly until the voltage exceeds the dielectric capability of the bearing grease, which leads to a frequently repeated flash-over current and in time can cause electroplating and pitting of balls and races. Numerical simulations are used to explore characteristic parameters (such as frequency, dv/dt, di/dt, motor running speed, etc.) of the bearing, and optimized by matching the experimental data, and eventually, predict the failure time of the bearing.
 A. von Jouanne, P. Enjeti, W. Gray, âApplication Issues for PWM Adjustable Speed AC Motor Drives,â IEEE Industry Applications Magazine, Sept/Oct. 1996, pp. 10-18. Prize Paper Award.