Eccentricity fault detection - From induction machines to DFIG-A review

Induction machines (IMs) are widely used in different applications. Unpredicted breakdown of these machines usually leads to costly downtimes and repairs. These expenses can be minimized using proper condition monitoring techniques. Eccentricity fault is one of the widespread faults causing machine malfunction; its detection could be useful for prevention of harmful consequences. In this paper, different works on eccentricity diagnosis of IMs with different types of supply have been reviewed. It commences from the simplest open-loop machine, and by considering torque variation and inverter switching gradually turns to complicated closed-loop machine with different control strategies. While in most cases, current is used for condition monitoring, in some instances power and voltage are employed for fault diagnosis. Due to extensive use of IMs in wind turbines as doubly-fed induction generator (DFIG), in addition to declaration of importance of eccentricity fault diagnosis in DFIG, detection of eccentricity fault in DFIG is also reviewed.