A NOVEL METHOD FOR COGGING TORQUE REDUCTION IN PERMANENT MAGNET BRUSHLESS DC MOTOR USING T-SHAPED BIFURCATION IN STATOR TEETH

A variety of techniques are available to reduce cogging torque in Permanent Magnet Brushless DC (PMBLDC) motors. In general, all the techniques are meant for effectively reducing the cogging torque. This paper presents a new technique for cogging torque reduction in a radial flux surface mounted PMBLDC motor by applying the proposed T-shaped bifurcation method in the stator teeth of a PMBLDC motor. The Finite Element Analysis (FEA) is carried out for the Tshaped bifurcation method applied to a PMBLDC motor, and analysis is done using Virtual Work (VW) method. The CAD software package MagNet has been used to completely analyze the T-shaped bifurcation based PMBLDC motor. FEA and CAD simulated results are compared for the reduction of cogging torque values. It is found that the cogging torque reductions in the two methods are nearly the same. The cogging torque and the flux density values of the motor calculated using the proposed T-shaped bifurcation method are compared with the corresponding values of the recently introduced Reduced Stator Slot Width method. The proposed T-shaped bifurcation is very effective compared to the existing techniques in reducing the cogging torque.