Magnetic Field Analysis of Multi‐Segment Modulated Pole Motors Based on the Air Gap Domain Multi‐Harmonic Method

ABSTRACT This article improves the traditional subdomain model based on the theory of air gap magnetic field modulation and proposes an analytical method for the magnetic field of air gap domain multi‐harmonics. The improved model builds on the subdomain model by adding more harmonic coefficients to the air gap domain to comprehensively represent the harmonic characteristics and spatial frequency of the motor's magnetic field. The improved model effectively solves the problem of inaccurate magnetic field results when analysing multi‐pole pairs motors using the traditional subdomain model and reduces the matrix dimension during analytical calculations. The computational object in this paper has a large number of pole pairs and multi‐segment modulated poles. The analytical results are compared with finite element results and prototype experiments to validate the accuracy of the air gap domain multi‐harmonic method. The improved model reduces matrix dimensions and shortens analytical computation time. It may also decrease computational load during iterations, thereby accelerating the iterative process and providing insights for nonlinear magnetic field analysis.