Acoustic Analysis of Electric Motors in Noisy Industrial Environment

This paper presents a method for the acoustic analysis of electric motors in noisy industrial environments. Acoustic signals were measured via acoustic camera 48-microphone array, which has the capability to localize a sound (or sounds) source and, in turn, separate those sounds from intrusive background noise. These acoustic analysis results are then compared with vibration measurements; vibration monitoring is a well-known and established technique used in condition monitoring, and in this work vibration measurements were used as a reference signal for assessment of the value of the acoustic measurements. Vibration signals were measured by piezoelectric accelerometers. Two induction motor cases were examined — a healthy motor case, and a combination of static eccentricity with soft foot case. As shown, acoustic analysis appears to be a valuable technique for condition monitoring of electric motors — particularly in noisy industrial environments.