Effects of samarium cobalt permanent magnet on the performance of polyphase hysteresis-reluctance motors

Effects of samarium cobalt permanent magnet on the steady-state performance of hysteresis-reluctance motors are presented. Based on the parallelogram approximation of the B-H loop for the semi-hard hysteresis materials of 36% colbalt-steel and Alnico 5, analytical expressions to predict the motor terminal characteristics are given. Experimental verification of the theoretical analysis is also provided. It leads to some useful conclusions, enabling the designers to choose between the types of permanent magnet materials for different drive requirements.