Multi-objective optimal design of an axial-flux permanent-magnet wheel motor for electric scooters

• Published in: IET electric power applications Vol. 8; no. 1; pp. 1 - 12
• Main Authors: Yang, Yee-Pien, Lee, Chung-Han, Hung, Po-Chang
• Format: Journal Article
• Language: English
• Published: London The Institution of Engineering and Technology 01.01.2014; Institution of Engineering and Technology; The Institution of Engineering & Technology
• Subjects: 0D model; 1D magnetic circuit model; 3D finite element method; air gaps; air‐gap distribution function; Applied sciences; axial‐flux permanent‐magnet wheel motor; Density; driving cycle ECE‐40; electric scooter; electric vehicles; Electrical engineering. Electrical power engineering; Electrical machines; electronic gearshift; Exact sciences and technology; finite element analysis; gears; high torque density; magnetic circuits; magnetic flux; Miscellaneous; multiobjective optimal design; permanent magnet motors; torque; Transformers and inductors; wheels; zero‐dimensional model; magnetic flux; wheels; multiobjective optimal design; electric vehicles; high torque density; electric scooter; torque; electronic gearshift; finite element analysis; axial-flux permanent-magnet wheel motor; air-gap distribution function; 1D magnetic circuit model; air gaps; magnetic circuits; 0D model; zero-dimensional model; driving cycle ECE-40; permanent magnet motors; gears; 3D finite element method; Performance evaluation; Prototype; High density; Magnetic model; Magnetic circuit; Multiobjective programming; Motor torque; Permanent magnet motors; Gap function; Gear; Optimal design; Finite element method; Air gap; Distribution function; Axial field; Electric motor
• ISSN: 1751-8660; 1751-8679; 1751-8679
• DOI: 10.1049/iet-epa.2013.0026

This study proposes a systematic process of a multi-objective optimal design of an axial-flux permanent-magnet motor for electric scooters. The preliminary design uses a zero-dimensional (0D) model to determine the number of slots and poles and initial sizes of the motor according to the driving requirements of the scooter. The optimal design process uses a 1D magnetic circuit model with an effective air-gap distribution function, whereas searching for a set of motor parameters that minimise or maximise motor performance indices such as torque, torque density and torque ripple. The final design is verified and refined by the 3D finite element method. The resulting prototype motor features high torque density of 8.94 Nm/kg and electronic gearshifts between low and high gears. According to their efficiency maps, the driving-cycle efficiency is estimated as 57% for the electric scooter to operate on the driving cycle ECE-40.