Modeling and Analysis of Interturn Short Fault in Permanent Magnet Synchronous Motors With Multistrands Windings

This paper develops an analytical model for describing the behaviors of the interturn short fault in the permanent magnet synchronous motors (PMSMs) with multistrands windings. An analysis of the fault modes resulted from the deterioration of insulation in multistrands windings are first carried out. According to the possible fault influences, a consistent expressions of interturn short-circuit current, phase voltages, and electromagnetic torque for modeling the different modes of interturn short faults are then derived. The proposed model allows studying the postfault performances of these motors under transient and steady state, including fault resistance, quadrature- and direct-axis current, or speed variations. Both finite-element analysis and experimental results demonstrate the effectiveness of the developed model for predicting the interturn short-circuit behaviors in the PMSMs with multistrands windings.