Analytical model for magnetic field distribution and electromagnetic characteristics analysis of permanent magnet synchronous motor with toroidal winding stator and sinusoidal Halbach array rotor

This paper presents an analytical model for the rapid examination of the magnetic field distribution and electromagnetic characteristics of a Permanent Magnet Synchronous Motor (PMSM) featuring a toroidal winding stator (TWS) and a sinusoidal Halbach array rotor (SHAR). The analytical model for magnetic field distribution is established by solving the governing Laplace’s and Poisson’s equations of the vector magnetic potential. The no-load magnetic field distribution from SHAR and the magnetic field induced from the armature reaction are individually analyzed. According to superposition theory, the complete magnetic field distribution is derived. Furthermore, an analytical model for motor electromagnetic characteristics, including motor inductances, electromagnetic torque, and motor on-load induced voltage, is formulated. Lastly, the precision of the analytical model is verified through finite element analysis (FEA) simulations across various operational points.