CPC G01R 31/72 (2020.01) [G01R 31/343 (2013.01); G01R 31/346 (2013.01); G01R 31/52 (2020.01)] | 25 Claims |
1. A method of detecting a rotor bar fault of an electrical machine, said method comprising,
acquiring a set of online signals from the electrical machine over a period, said set of online signals comprising at least one vibration signal, and a summed signal of magnetic flux signals, each magnetic flux signal obtained from a respective flux sensor positioned on an external surface of the electrical machine,
wherein the summed signal of magnetic flux signals is obtained by acquiring and summing a set of p flux signals to obtain a total flux signal, wherein the set of p flux signals is acquired from p flux sensors positioned along a circumference of a cylindrical frame of the electrical machine, such that any two adjacent flux sensors along the circumference of the cylindrical frame have an angular separation of 360/p degrees with respect to the longitudinal axis of the cylindrical frame, wherein p represents the total number of poles of the electrical machine;
extracting an online anomaly indicator value from the set of online signals;
comparing the online anomaly indicator value with a baseline anomaly indicator value of a corresponding loading condition; and
determining presence of a broken or cracked rotor when the online anomaly indicator value deviates from the baseline anomaly indicator value by a threshold.
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