Design of novel magnetic flux barrier for reducing cogging torque in IPM type BLDC motor

This paper introduces a rotor core in an interior permanent magnet type brushless DC motor. The rotor core consists of a rotor surface having a non-uniform air gap and a novel magnetic flux barrier. We show that, in the rotor core, the rotor surface having the non-uniform air gap effectively reduces the cogging torque while the optimized magnetic flux barrier reduces the cogging torque, and increases the average torque and the efficiency.