Analysis of Inter-Turn-Short Fault in an FSCW IPM Type Brushless Motor Considering Effect of Control Drive

Abstract

A comprehensive analysis of inter-turn-short fault (ITSF) in a fractional slot concentrated winding (FSCW) interior permanent magnet synchronous motor (IPMSM) is presented in this article. During online fault detection, the fault signatures can be influenced by the controller action in a closed-loop control system. Therefore, this study focused on the comparison of the ITSF characteristics in an IPMSM using open-loop and closed-loop control drives. The variation rate in various parameters, such as flux density, input current, circulating current, torque ripple, and vibration under healthy and ITSF conditions are compared. Conventional six-step square-wave control (SSC) and field-oriented control (FOC) drives are respectively used for open-loop and closed-loop analysis of ITSF. Furthermore, this study also focuses on mitigating the capability of the control drives for achieving extended postfault life of the motor. Based on our analysis a fault mitigating strategy for the benchmark IPMSM is also suggested. A multidomain cosimulation technique is used to integrate the finite element method-based model of IPMSM with the control drives under different severities of ITSF for the simulation. Finally, experiments on a three-phase 400-W IPMSM are performed for verification. The result shows that in the FSCW machine the ITSF can be mitigated and FOC has a better capability of ITSF mitigation than SSC.