Cm. Riley et al., A METHOD FOR SENSORLESS ONLINE VIBRATION MONITORING OF INDUCTION MACHINES, IEEE transactions on industry applications, 34(6), 1998, pp. 1240-1245
This paper proposes a method for sensorless online vibration monitorin
g of induction machines based on the relationship between the current
harmonics in the machine and their related vibration harmonics. Initia
lly, the vibration monitoring system records two baseline measurements
of current and vibration with the machine operating under normal cond
itions. The baseline data is then evaluated to determine the critical
frequencies to monitor on-line. Once these frequencies are determined,
the baseline vibration measurement is simply used to scale the curren
t harmonic signal to an estimated vibration level. Based on theoretica
l analysis, simulations results, and the experimental results shown he
re, a linear relationship between the current harmonics and vibration
level can he assumed. The results of two experiments on a three-phase
230-V 10-hp induction motor operating under no load are discussed and
show the feasibility of this method for sensorless on-line vibration m
onitoring.