Optimal design of motor shape and magnetisation direction to obtain vibration reduction and average torque improvement in IPM BLDC motor

Abstract

An optimal design for the interior permanent magnet (IPM) motor is proposed to reduce vibration and increase average torque, based on simultaneous consideration of the rotor d-axis notch shape, the stator chamfer angle, and the magnetisation direction. The notch shape of the rotor and the chamfer of the stator tooth shape were first reviewed in order to reduce the vibration of the IPM motor; however, the optimal shapes for reduced vibration also reduced the average torque. Then, a design optimisation for average torque improvement was performed considering the magnetisation direction and the vibration reduction based on the modelled stator and rotor shapes. Finally, the validity and superiority of the optimised design were confirmed by manufacturing and testing a prototype motor.