Structure and Characteristics of Interior Permanent Magnet Synchronous Motor with Bonded Rare-Earth Magnets

Abstract

Although motors that use rare-earth permanent magnets typically exhibit high performance, high costs and concerns about the stability of raw material supplies are leading to their decreased production. In this research, the magnet shape, the number of magnet layers and the number of poles are investigated to obtain target rated torque under the same external diameter and stack length. Next, the characteristics of an IPMSM with bonded rare-earth magnets and an IPMSM with sintered rare-earth magnets are compared under the same current. Moreover, the efficiency of the models are compared under the constant output power.