Analytical Calculation of Cogging Torque Considering Core Reluctance by Using Equivalent Field Winding Model

This article proposes a cogging torque calculation method that considers stator teeth reluctance using an equivalent field winding model. Firstly, analyze the variation law of stator teeth potential with rotor position angle under the action of core reluctance. Then, simulate the tooth potential change using equivalent winding excitation, and transform the core with reluctance into ideal. This transformation does not change the potential distribution on the boundary of the airgap region and the torque calculation result, thus transforming the original cogging torque into the sum of the component caused by cogging structure with infinite permeability core and the component generated by the linkage between equivalent field windings and rotor flux. This article presents calculation methods for the two components, and takes a 12-slot 10-pole surface-mounted motor as an example for model proving. The calculated results are consistent with the finite element model results.