Multi-objective optimization of a spoke-type permanent magnet motor with fractional-slot concentrated windings for EVs

Abstract

Purpose

This paper aims to propose a spoke-type fractional-slot concentrated windings (FSCW) PM machine for EVs driving system to improve torque density. To further improve electromagnetic performance, the multi-objective optimization design is processed based on response surface (RS) model and simulated annealing cuckoo search (SA-CS) algorithm.

Design/methodology/approach

The spoke-type FSCW PM machine is designed and optimized to meet the requirement of EVs driving system. First, a spoke-type FSCW PM machine is designed and some of key parameters are obtained based on equivalent magnetic circuit (EMC) method. Then, the RS model and modified SA-CS algorithm are proposed to obtain higher torque, lower torque ripple and higher efficiency.

Findings

After verification by finite element method for no-load and load performance, the optimal machine has higher torque density, lower torque ripple and higher efficiency compared with initial machine. Finally, a 20 kW prototype is manufactured and tested to verify the validity of the proposed optimization design method.

Originality/value

This paper designs a high torque density spoke-type FSCW PM machine, which is superior for EVs driving system. Meanwhile, a novel modified SA-CS algorithm is applied to the field of electrical machine multi-objective optimal design.

Citation

Liu, S. and Huang, J. (2021), "Multi-objective optimization of a spoke-type permanent magnet motor with fractional-slot concentrated windings for EVs", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 40 No. 3, pp. 561-578. https://doi.org/10.1108/COMPEL-08-2020-0278