Modeling Analysis and Tolerant Capability for Stator Winding Interturn Fault in Synchronous Reluctance Motor With Series and Parallel Connected Windings

This work deals with development of analytical models for synchronous reluctance motor (SynRM), under stator interturn fault (SITF), considering series and parallel connected windings. The developed models are first of its kind for SynRM, which considers cross flux coupling interactions between healthy and faulty coils in the same winding, along with other phase windings. By adopting the proposed modeling approach, consistent equations in abc and dq coordinates suitable for analyzing performance metrics such as phase currents, electromagnetic torque, and dq voltages have been derived, which allows studying the post fault operations and fault diagnosis features, at different fault conditions. The key fault features of SITF such as the fault current and third harmonic in the faulty phase current have been considered, in an attempt to evaluate the motor's ability to tolerate interturn fault, in both series and parallel winding configurations. The experimental results agree well with the theoretical analysis and it demonstrates the effectiveness of the developed models for analyzing the machine behavior under SITF in the SynRM, with series and parallel connected windings. The investigation also points out that parallel winding SynRMs (P-SynRMs) are more challenging to diagnose and more fault tolerant to the SITF than the series winding SynRMs (S-SynRMs).