Design, fabrication and performance estimation of BLDC motor for electric vehicles

Permanent Magnet synchronous motors are widely used for the application of electric and hybrid vehicles. BLDC motors are preferred more among other permanent magnet motors because of higher efficiency. Also, Brushless DC motors has an advantage of being smaller in size and has less noise. The main issue with this motor is cogging torque. Reduction of cogging torque is obtained by various methods such as fractional slots per pole, changing magnet type in the rotor. The objective of this work is to fabricate a BLDC motor by optimizing magnet pole arc and changing the rotor type. The modification of the rotor type depends on the selection of magnet materials / grades as per the design. Rare earth materials with different grades are used for this work. These magnets offer high efficiency, but the disadvantage is that these magnets are expensive. This work elaborates the investigation of back EMF, speed torque characteristics, cogging torque, efficiency based on the material selection. MotorSolve has been chosen here for the simulation of 24V, 3 phase, 4 poles, 27 slots for the BLDC motor and simulation has been validated with the experimental investigation.