A Disassembly-Free Offline Detection and Condition Monitoring Technique for Eccentricity Faults in Salient-Pole Synchronous Machines

A novel scheme to reliably monitor the condition of static and dynamic eccentricity (DE) faults in salient-pole synchronous machines (SPSMs) through the standard short-circuit test is proposed in this paper. The detection technique is based on offline current signature analysis that does not require machine disassembly. The procedure is unaffected by machine saturation or supply voltage harmonics. In this scheme, DE fault is monitored by exploiting the presence of inherent static eccentricity (SE), whereas SE fault monitoring is achieved using residual estimation technique. The proposed method is found to work for both star and delta-connected machines. Results obtained from an experimental three-phase 2-kW SPSM have been used to validate the proposed eccentricity condition monitoring method.