Condition monitoring of stator windings in induction motors. II. Experimental investigation of voltage mismatch detectors

For pt.I see ibid., vol.38, no.5, p.1447-53 (2002). Condition-based maintenance (CBM) of industrial equipment is generally recognized as being the most cost-effective means for improving equipment availability. However, a prerequisite to successful implementation of CBM is a reliable detector of failing components. One such detector, termed the effective negative-sequence impedance, had previously been identified as an indicator of an induction motor stator winding degradation. However, a limitation of this detector is that it may not change in a predictable manner for extremely low levels of deterioration. Presented in this paper is an experimental investigation of a technique for online detection of induction motor stator winding degradation that addresses this difficulty. It begins with a brief description of the detectors, followed by a detailed description of the experimental setup, the experiments conducted, and results.