RADC-TR-77-408, FINAL TECHNICAL REPORT: ELECTRIC MOTOR RELIABILITY MODEL (DEC-1977) [DTIC: ADA050179]

RADC-TR-77-408, FINAL TECHNICAL REPORT: ELECTRIC MOTOR RELIABILITY MODEL (DEC-1977) [DTIC: ADA050179]., 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.