Reduction of torque ripple and increase of torque capacity of BLDC motor

This paper uses the idea of increasing the phases of Brushless DC motors (BLDC motors) with the purpose of Performance improvement of this motors. At first, a new model for the drive of 9-phase BLDC motor is studies. This model is simulated and run by Matlab/Simulink software. Then, the obtained results including Steady-state and transient characteristics, are compared with the results of 3, 5 and 7-phase models. The results of comparison show the advantages of increasing number of phases of BLDC motor, including considerable reduction of torque ripple, increase of starting torque and partial improvement in motor efficiency.