Phaselet-Based Method for Detecting Electric Faults in $3\phi$ Induction Motor Drives—Part II: Performance Evaluation

This paper presents the online implementation and performance evaluation of the phaselet-based method for detecting electric faults in induction motor drives (IMDs). The online implementation of tested fault detection method is achieved using a digital signal-processing board, where the inputs are the 3φ stator currents and the output is a trip signal. The desired fault feature is extracted using six digital high-pass filters, whose coefficients have been obtained using phaselet basis functions that are generated by the biorthogonal 2.1 scaling function. The performance of the phaselet-based fault detection method is tested for two different IMDs that are fed across-the-line and through a frequency drive system, when operated at different loading levels. Experimental test results show accurate, reliable, and fast fault detection, along with negligible sensitivity to the speed, loading levels, IMD ratings, and fault type.