Comparison between parallel and radial magnetization in PM fractional machines

In PM machines with curve shaped magnets the magnetization can have parallel or radial direction. The paper aims to evaluate the impact on the motor characteristics of magnetization direction, by means of simulation and experimental results. The proposed analysis is based on two different magnets technologies: one technology is industrially well established (anisotropic ferrite), while the other one is unconventional (rare-earth powder with phenolic resin bonded magnets). The case study is based on fractional horse power motor for electro-fan automotive applications: a concentrated windings fractional slots PM machine with external rotor.