Influence of Rotor Structure on Fault Diagnosis Indices in Two-Phase Switched Reluctance Motors

In this paper, the influence of rotor structure on fault diagnosis indices variations is studied for switched reluctance motors (SRMs). To achieve this aim, two novel SRMs, namely a slanted-rotor SRM (SL-SRM) and stepped-rotor SRM (ST-SRM), are analyzed and tested, accompanied with a conventional SRM. Accordingly, three popular indices, mutual inductance index (MII), radial force index (RFI), and torque index (TI), variations are offered to diagnose the eccentricity fault occurrence evaluation in different structures. To assess motor characteristics, the variations of flux linkage, flux density, and inductance as some of the electromagnetic traits of SRM, SL-SRM, and ST-SRM are obtained and analyzed utilizing 3-D transient finite element method (3-D-TFEM). Afterward, all three motors are subjected to eccentricity fault and the fault diagnosis indices are obtained individually in various levels of fault severities. Briefly speaking, the effect of rotor structure on all three of these indices is analyzed first. Second, the most robust and fault tolerant index independent of the motor´s structure is introduced for a specific application. To verify the simulation results, experimental findings are also included.