Optimal Design of a New Interior Permanent Magnet Motor Using a Flared-Shape Arrangement of Ferrite Magnets

This paper proposes the optimal design of a new interior permanent magnet (IPM)-type brushless dc (BLdc) motor using low-price ferrite magnets. The new IPM motor has the structure of C-type ferrite magnets featuring a flared shape to obtain high motor performance. To maximize the flux density and minimize the torque ripple, the flared-shape rotor structure is optimized by algorithms, such as the Kriging method based on Latin hypercube sampling and a genetic algorithm. The analyses of basic and optimal designs utilize a 3-D finite-element method, and then, the validity of the optimal design is verified through fabrication of actual prototypes.