Fault diagnosis and condition monitoring of electrical machines - A review

Electrical equipments are the workhorses of industry; their failure may result in complete shut down of a plant or even cause an unexpected disaster. Researchers had pursued rigorously various diagnostic approaches for electrical machines. Apart from analyzing the conventional vibration, current, voltage signals people are trying to explore fault signatures from torque, power, speed, flux etc. Methods such as offline/online, with/without additional sensor, model-based, signal-based etc. are being explored vastly. A number of signal processing techniques and fault detection decision-making tools are being reported frequently. Undoubtedly this field is vast in scope. Hence keeping this in mind to avoid repetition as well to facilitate future research a brief review is presented in this paper. Nearly 80% electrical motors used in industries are induction motors and hence industries depend on the performance of them to a great extend. This paper will mainly concentrate on induction machines with a very brief review of other machines.