Characterization of Rare-earth Permanent Magnet for Electric Motor Design

摘要

This thesis proposes a method to reconstruct the demagnetization curve of rare earth magnet for design of surface-mounted permanent magnet motors This thesis first discusses the impulse magnetization using a magnetizer with a fixture The necessary magnetic field strength for full magnetization is determined by finite element analyses After magnetization measurements of flux density on the magnet surface are performed along with a C-core to determine the magnet model i e the demagnetization curves for electric motor design A magnetic circuit model is developed to work with the C-core measurement for modeling the magnet The demagnetization curve obtained is then compared with that provided by the supplier to demonstrate the effectiveness of the modeling Second the magnetization pattern of ring magnet is analyzed in order to achieve sinusoidal back-electromotive force waveform for surface-mounted permanent magnet motors The cogging torque torque ripple can thus be reduced when the motor is driven by sinusoidal current This is validated by simulation

獎項日期	2016 8月 18
原文	English
監督員	Min-Fu Hsieh (Supervisor)