Analytical Prediction of Cogging Torque for Interior Permanent Magnet Synchronous Machines

In this paper, a combination of Lumped-Parameters Model, Quasi-Poisson's equations and Conformal Mapping methods is used for predicting radial and tangential air gap flux density of Interior Permanent Magnet Synchronous Machine for calculation of cogging torque. In the proposed method, Lumped Parameters Model is used for calculation of saturation and flux leakage. Quasi-Poisson's equation is used for forming radial and tangential flux density in slotless stator, and finally Conformal Mapping is used to account for slot effects. Using the results of this method, cogging torque waveform can be calculated using Maxwell stress tensor and virtual work methods. To validate the method, results are compared with Finite Element Method results for a candidate Interior Permanent Magnet Synchronous Machine.