Electromagnetic Performance Prediction for the Symmetrical Dual Three-phase Surface-mounted PMSM under Open-phase Faults Based on Accurate Subdomain Model

The paper presents an accurate analytical subdomain model for predicting the electromagnetic performance in the symmetrical dual three-phase surface-mounted permanent magnet synchronous machine (PMSM) under open-phase faulty conditions. The model derivations are extended from previous accurate subdomain models accounting for slotting effects. Compared with most conventional subdomain models for traditional three-phase machines with nonoverlapping winding arrangement, the subdomain model proposed in this paper applied for the 24-slot/4-pole dual three-phase machine with symmetrical overlapping winding arrangement. In order to investigate the postfault electromagnetic performance, the reconfigured phase currents and then current density distribution in stator slots under different open-circuit conditions are discussed. According to the developed model and postfault current density distribution, the steady-state electromagnetic performance, such as the electromagnetic torque and unbalanced magnetic force, under open-circuit faulty conditions are obtained. For validation purposes, finite element analysis (FEA) is employed to validate the analytical results. The result indicate that the postfault electromagnet performance can be accurately predicted by the proposed subdomain model, which is in good agreement with FEA results.