Radial flux signature analysis for identifying source unbalance and stator turn fault in cage motors using radial flux sensing coil

This paper suggests a distinct method having advantages over classical MCSA and Stray flux analysis techniques. The radial flux sensing coil (RFSC) proposed in this study provides the wanted ease of stator turn fault (STF) detection and simplicity of implementation. The RFSC has been found to be more effective compared to external flux sensors and current sensors for detection of unbalanced source and STF. The proposed simplified, inexpensive technique has yet not been reported in literature. The new result is that the RMS, fundamental, third and total harmonic distortion (THD) analysis of the voltage spectra of the RFSCs have been found to exhibit variations in relation to the severity of inter-turn faults and supply unbalance as compared to the healthy condition. The mathematical theory of the technique is provided and supported by an experimental validation.