Reducing Cogging Torque in Interior Permanent Magnet type BLDC motor by Flux barriers in the rotor

회전자부의 자속장벽 설치를 통한 IPM type BLDC 전동기 코깅 토오크 저감에 대한 연구

Several techniques have been adopted in motor design of interior permanent magnet (IPM) type brushless DC (BLDC) motor to minimize cogging torque. IPM type motor has better ability in the centralization of flux than surface-mounted permanent magnet (SPM) type BLDC motor. So, the structure of IPM type BLDC motor has high saliency ratios that produce additional torque. However, this structure has a significant cogging torque that generates both vibration and noise. This paper describes new technique of the flux barriers design for reduction of cogging torque of IPM type BLDC motor. To reduce the cogging torque, flux barriers are applied in the rotor. Changing the number of barrier, the cogging torque is analyzed by finite clement method(FEM).