Winding Function Model for Detecting Demagnetization in Permanent Magnet Synchronous Machines

Permanent magnet synchronous machines (PMSMs) are widely used in electromechanical actuators and energy systems, thus always work in dynamic operations, and expose external stresses in hash environments. Under such stresses, the PMSM might face challenges of overloading under high currents or voltage, and vibration from the environment, resulting in demagnetization fault in the rotor and inter-turn short circuit fault in the stator winding. This paper presents an analytical model for the faulty machine based on improved winding function theory. The model could be used to formulate the characteristic frequencies associated with the faults. These frequencies could be used as the indicator for incipient fault detection systems. The developed model is numerically verified and experimentally validated from an in-house experimental setup.