A Novel Interturn Short-Circuit Diagnosis Method for SRMs Based on Unaligned Inductance Identification Using FOTSMO

This article proposes a novel interturn shortcircuit (ITSC) fault diagnosis method for switched reluctance motors (SRMs) based on unaligned inductance, utilizing a fractional-order terminal sliding mode observer(FOTSMO). The method addresses common ITSC faultsthat occur during SRM operation. First, the electromagneticcharacteristics of the SRM under ITSC fault conditions considering the short-circuit current are measured, and theimpact of ITSC faults on the characteristics is analyzed.A linear model of the SRM is then constructed by constraining the position and current parameters. To enhanceobserver robustness, a FOTSMO is designed to estimate theunaligned inductance. Simultaneously, a novel reaching lawis introduced to mitigate chattering. Based on experimentalresults, a definition of ITSC fault severity level is proposed,incorporating both the short-circuit current and the numberof short-circuit turns. To validate the effectiveness of theproposed method, experiments are conducted under multiple operating conditions. The results demonstrate that theproposed method can achieve ITSC fault diagnosis, particularly in cases with a low number of short-circuit turns, andis well-suited for high-speed operating conditions.