Optimizing BLDC Motor Design for EVs using Pole-Slot Configuration Analysis

Brushless DC (BLDC) motors are widely used for propulsion in electric vehicles because of many advantages such as long life, higher speed range capability, compact design, improved torque capability, etc. This paper aims to study and evaluate the different designs of direct-drive outer-rotor BLDC motor in ANSYS electronics software (AES) environment. The finite element analysis (FEA) on the load-speed characteristic of the BLDC motor is carried out using AES. And performance under different constructional pole-slot configurations with same motor rating (1.5 kW, 48 V) are studied. The study is mainly to determine the best pole-slot configuration in motor design in achieving a desired load-speed characteristic for electric vehicle applications. The findings with AES-based FEM analysis are compared with that obtained analytically using theoretical formulations and show good resemblance. The presented analysis in the paper could be valuable indication in designing appropriate BLDC motor for electric vehicle applications.