Analytical Calculation of Electromagnetic Force of Surface-Mounted Permanent-Magnet Machine with Stator Notch using Subdomain Method

In this paper, an analytical method based on subdo-main (SDM) is proposed to calculate open-circuit electromagnetic force of a surface-mounted permanent-magnet (SPM) machine with stator notch. SDM can precisely consider the effect of notch structure in magnetic field distributions rather than magnetic equivalent circuit (MEC) and conformal mapping (CM), and is faster than finite element methods (FEM). Therefore, the proposed method in this paper will help to predict electromagnetic force in the design stage. To verify the proposed method, the air-gap flux density obtained from FEM and the proposed method is compared. In addition, the effect of the stator notch on electromagnetic force regarding the depth and the width is studied through spatial and temporal harmonic analysis.