Non-invasive detection of winding short-circuit faults in salient-pole synchronous machine

Abstract

This study presents an analytical and experimental method for detecting internal turn-to-turn short circuits both in the rotor or in the stator in Salient-pole Synchronous Generator Machines (SSGM) connected to local power grid. Two main measurements are proposed to confirm or discard these electric faults: External Magnetic Flux Density (EMFD) and External Housing Vibrations (EHV). In the event of a short-circuit winding fault, a correlation between EMFD and EHV is confirmed. Furthermore, the electric power injection dependency is introduced in order to establish the validity range of this method. In this study, only non-invasive and on-line equipment are required to diagnose the SSGM. A diagnostic tool has been developed to show the viability of an operative wireless monitoring system in an industrial environment.