Faults Diagnosis in Induction Motors Through Thermal Mapping Produced by the RDTS System

In the industry, production lines depend on small and medium-sized electrical machines, and for this reason, continuous monitoring of these machines is important to avoid unexpected interruptions. Excessive rise in temperature during electric motor operation is usually associated with several causes, including voltage unbalance and overload. This article presents the measurements taken using a Raman Distributed Temperature Sensing (RTDS) device with 1 m spatial resolution to identify induction motor (IM) faults. In this regard, an algorithm to improving spatial resolution through signal processing allows measuring lengths of up to 15 cm. Experimental tests showed that it was possible to identify the temperature increase in four slots with an improvement of 60%. In addition, it was possible to detect faults in conditions of unbalanced voltage through temperature measurements. The proposed method shows that the measurements acquired by the distributed sensors installed in the IM stator allow thermal mapping of the machine’s entire structure.