Analytical Comparison Between Ferrite Core and Steel Laminations Losses of Multi-Polar Brushless DC Motor

This paper presents an analysis of the stator core losses in two kinds of 3-phase 32-pole brushless DC motors. One stator is manufactured by ferrite and the other is steel laminations. The losses are evaluated by performing time-stepped finite-element analysis and the results are used to evaluate the suitability of the models. The theoretical analysis and experimental results derived from the inverter-controlled BLDC motor drives are presented for confirmation. Experimental results show that the motor with ferrite stator has higher maximum speed and efficiency than those of steel laminations. On the other hand, the motor with steel laminations produces higher torque than that of ferrite material. Based upon these comparison results, ferrite core stator is very promising for low-torque and high-speed applications.