DESIGN AND FIELD-WEAKENING PERFORMANCE OF PERMANENT-MAGNET RELUCTANCEMOTOR WITH 2-PART ROTOR/

A synchronous motor with two-part rotor is described whose rotor compr ises a surface-magnet part and a reluctance part mounted adjacent to e ach other on the same axis. An axially laminated construction is used in the reluctance part to achieve a high saliency ratio. Machine param eters and physical design details are selected to obtain constant-powe r characteristics over a 3:1 speed range by field-weakening. Test resu lts demonstrate the achievement of the desired characteristics, in goo d agreement with computed predictions. The two-part rotor construction is thus a candidate for applications such as electric vehicles.