Model Based Stator Interturn Fault Analysis in Synchronous Reluctance Motor Drives

Recently, Synchronous Reluctance Motors (SynRM) are finding place in several applications such as electric vehicles, aerospace, renewable and marine due to their inherent advantages such as the absence of rare earth materials and rotor windings, high performance, no demagnetization effects, and low cost. Therefore, the need to study, analyze and diagnose the fault at an early stage is becoming crucial for these machines. This work aims to develop analytical models necessary for incipient Stator Inter-Turn Faults (SITF) diagnosis on SynRM drives. A detailed analysis of SynRM with SITF has been attempted to comprehend the fault current behavior at various fault severities and operating conditions. Furthermore, steady state analysis has been carried out, by developing the sequence component models, which are critical for designing model-based diagnosis techniques. A method for the estimation of the fault currents is developed, which could help in post-fault operations of the drive, for bringing the fault current to a safe value. The conclusions of this study will be helpful for developing diagnosis techniques for SynRM drives, and to plan the post-fault operations. The experimental validation has been performed in a laboratory prototype using 3.7kW SynRM drive.