| Title |
A Study on the Reduction of Cogging Torque of Outer-Rotor Type BLDC Motor for Washing Machines |
| Authors |
김재민(Kim Jae-Min) ; 장철혁(Chang Cheul-Hyeok) ; 정태경(Chung Tae-Kyung) |
| Keywords |
BLDC Motor ; Back Ernf ; FEM ; Cogging Torque |
| Abstract |
This paper deals with the reduction of cogging torque of a outer-rotor type BLDC motor mainly used for washing machines. The motor comprises permanent magnet outer-rotor and stator with coils and core. This structure inherently produces vibration and cogging torque because of uneven reluctance according to rotation of the rotor. Up to now, adopted a type of 24 magnet pole and 36 slot-stator. This generates high main torque but accompanies comparatively large cogging torque. This paper proposes a 32-pole 36-slot type motor which reduces cogging torque remarkably. The influence of cogging torque is varied according to pole-slot combinations. The characteristic of the motor was obtained by a two-dimensional finite element method coupled with a drive circuit. The performance of the proposed model is superior to that of the existing model because of the reduction of torque ripple and the improvement of back ernf wave form. |