Title: Analysis on cogging torque of driving in-wheel motor for electric vehicle

Authors: Qiping Chen; Hongyu Shu; Limin Chen; Bo Chen; Jianhui Du

Addresses: State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400030, China. ' State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400030, China. ' State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400030, China. ' State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400030, China. ' State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400030, China

Abstract: In order to reduce the torque fluctuation, vibration and acoustic noise of driving in-wheel motor for electric vehicle, this paper researches the generation mechanism and influence factors of cogging torque. Based on energy method and Fourier expansion, an analytical method is proposed to establish the expression of cogging torque, which can express its relation with design parameters. Based on the expression, the match of pole and slot, pole arc coefficient and permanent magnet eccentric distance are analysed and studied. Ansoft software is used to establish a time-varying movement electromagnetic field finite element model, which can compute the cogging torque about the different match of the pole and slot, different pole arc coefficient and different permanent magnet eccentric distance, in order to obtain the change regularity of the corresponding cogging torque. The conformity of the final simulation computation results with the theoretical analysis indicates this method can be used to provide a theoretical basis to make further optimal design of the new driving in-wheel motor and its control system, so as to reduce torque ripple of in-wheel motor.

Keywords: cogging torque; electric vehicles; finite element method; FEM; simulation; driving in-wheel motor; torque fluctuation; vibration; acoustic noise; design parameters; slot; pole arc coefficient; permanent magnet eccentric distance; electromagnetic field; motor control; torque ripple.

DOI: 10.1504/IJEHV.2012.048329

International Journal of Electric and Hybrid Vehicles, 2012 Vol.4 No.2, pp.148 - 160

Received: 23 Feb 2012
Accepted: 09 May 2012

Published online: 15 Apr 2015 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article