Characteristic analysis of Spoke-type IPMSM corresponding to the rib structure

In order that Spoke-type interior permanent magnet synchronous motor (IPMSM) can operate in high speed region, field weakening control is required. Also, the rotor should be mechanically robust for the reliability. Structurally, Spoke-type IPMSM can have the rib on the outermost of rotor. The rib helps extend operation range and prevent the scattering of permanent magnet and pole pieces in high speed operation. Also, it can affect the permanent magnet demagnetization. So in this paper, the effect of rib on the operation range, mechanical stress and permanent magnet demagnetization is analyzed. Finally, effect of rib thickness is analyzed and relation to high speed operation is presented.