Analysis of magnetization of magnet in the rotor of line start permanent magnet motor

Abstract

Line start permanent magnet motor (LSPM) is an effective model of a high-efficiency motor at a constant velocity. Post-assembly magnetization is necessary to reduce manufacture costs. The purpose of this paper is to design the magnetizing fixture and analyze the magnetization characteristics. First, the magnetizing fixture reducing the eddy current is designed. Second, the magnetization of NdFeB magnetized by the designed fixture is analyzed. The time-stepping finite-element method combined with the Preisach model is used to analyze the magnetizing magnetic field intensity and to calculate the magnetization vector. With the magnetization vector, the surface flux density and back-electromagnetic force of the LSPM are calculated and compared with experiment results, which, in turn, agree well with the analysis results.