DC Permanent Magnet Brushless Motor Performance Evaluation with Different Rotor Material Using FEMM

Abstract

This paper presents the performance evaluation of a 4 pole, 6 slots DC permanent magnet brushless motor. In order to obtain efficiency, EMF induced, copper losses, torque & cogging force, computer simulations were performed on this machine. Moreover different rotor materials have been used and tested in order to obtain the highest efficiency. Real time brushless DC motor dimensions were taken in order to design the motor by using Finite Element Method Magnetics (FEMM). The material used for the motor and the air gap was varied in order to obtain the best performance of the motor. The software employed in this research is Programming Language Lua based script embedded with FEMM for evaluating the results obtained. It was also observed that different rotor materials gave better induced EMF results and the smaller the air gap size the better flux density results. The motor performance with reasonable precision is predicted by mathematical calculation method.