Electric Motor Reliability Model

An existing data failure bank consisting of over 2000 actual fractional horsepower FHP motor failures was upgraded and utilized to develop a failure model for FHP motors. Motor failures were dominated by two failure modes i.e., winding failures and bearing failures. A mathematical reliability model was developed for each failure mode utilizing a Weibull cumulative distribution function and regression technique. Results of a literature survey of both failure modes were used to supplement failure data where required and verify the developed models. Failure modes were recombined into a competing risk cumulative distribution model for use in predicting overall motor life and failure rates.