Cogging torque analysis of interior-type permanent-magnet brushless DC motor used in washers

In this paper, a permanent-magnet brushless (BL) DC motor is analyzed for cogging torque reduction. The high cogging torque is an important side effect in permanent magnet BLDC motor since it causes torque ripple problems. A simple decrease in cogging torque can be achieved by changing some physical parameters such as magnet arc, slot openings, etc. In this work, some cogging torque minimization techniques are proposed and some simulation results are provided for 24-slot, interior-type BLDC motor used in washers.