Induction Motor Fault Signature Analysis using Vibration and Motor Current Signature Analysis ( MCSA )
8227 Hermitage Road, Richmond, VA, 23228
Published: September, 11 2015
Diagnostics of an induction motors is serious issue for improving plant asset reliability. Electro-mechanical malfunctions can lead to power loss, decrease in efficiency, current spikes, and other complications leading to premature failure of a motor. Motor current signature analysis (MCSA) and vibration data are commonly used for diagnosing induction motor problems. This paper will present a comparison of vibration and motor current signals for induction motor subjected to varying degrees of mechanical and electrical faults such as shorted turn, broken rotor bars, mechanical imbalance, rolling element bearing faults, and rotor eccentricity. The results of experiments performed on intentionally faulted motor will be presented. The effects of mechanical loading such as torque, unbalance, and misalignment loadings will be also discussed. The presentation will begin with a brief overview of modern signal processing techniques applicable to induction motor diagnostics. An introduction on the effects of variable frequency drives (VFD) on the distortion of measured signals and how to use the information positively to enhance diagnostics will be also presented. The results suggest that both motor current and vibration measurements are required for more complete diagnostics of induction motors. It will be shown how vibration analysis and MCSA complement each other and provide non-invasive cost effective means to monitor the health of induction motors.
Motor Current Signature Analysis ( MCSA )