A study on design of magnetization yoke of ferrite spoke-type permanent magnet synchronous motor considering demagnetization

The study proposed a design of magnetization yoke of ferrite spoke-type permanent magnet synchronous motor. A high magnetic field intensity(H) is required for the magnetization of permanent magnet, meaning that the analysis of nonlinear finite elements methods is needed considering saturation of core. The permanent magnet is placed deeply to the shaft especially in spoke-type motor. The high H, however, may cause demagnetization of surrounding permanent magnets, making the design of spoke-type magnetization yoke to be difficult. This study proposes the interpole winding to reduce the demagnetization of surrounding permanent magnets and analysis of power supply source considering magnetizer, derives the structure of optimized magnetization yoke to meeting the criteria of magnetization and demagnetization by analyzing field, and finally verifies the results of this study by manufacturing and testing.