Cogging Torque Minimization of High-Speed Spoke-Type Radial Flux Permanent Magnet Brushless DC Motor Using Core Bridge Width Variation Technique

Radial flux permanent magnet brushless DC motors have a significant drawback of high cogging torque despite having several benefits. To improve the overall performance of the interior permanent magnet brushless DC motor, this high-cogging torque must be reduced. This article presents the minimization of cogging torque in 4-pole/12-slot spoke-type radial flux permanent magnet brushless DC configurations having different envelope dimensions for three different electric vehicle applications through rotor side design variation. For exact electromagnetic field analysis, the finite element method is used. In-depth investigations have been conducted to analyze the impact of core bridge width variation on the cogging torque and average torque of the radial flux permanent magnet brushless dc motor. The validity of the analysis results is also clarified by comparing reference and improved models. As peak cogging torque is reduced, the core bridge width variation technique is found effective in reducing the cogging torque of the RFPMBLDC motor.