Study on Injection Molding IPMSM Using Sm-Fe-N Bonded Magnet

In this paper, we propose an interior permanent magnet synchronous motor (IPMSM) that applies bonded magnets made of Sm-Fe-N magnetic powder, which can be directly injection molded into the rotor. First, Sm-Fe-N magnetic powders with high residual flux density and high heat resistance were prepared by developing a magnetic powder manufacturing process that enables uniform phosphoric acid coating on the surface of magnetic powders. the motor performance was evaluated by two-dimensional finite element analysis when the developed magnetic powder was adopted for injection molding into the motor rotor. It was shown that the proposed Sm-Fe-N bonded magnet IPMSM has can achieve performance equivalent to an IPMSM with N-Fe-B sintered magnets using the same stator.