Modeling and analysis of field modulated permanent-magnet eddy-current couplings with a slotted conductor rotor

Issue title: Proceedings from the 17th International Symposium on Applied Electromagnetics and Mechanics (ISEM 2015)

Guest editors: Fumio Kojima, Futoshi Kobayashi and Hiroyuki Nakamoto

Article type: Research Article

Authors: Liang, Qinghua^a | Mo, Jinqiu^a | Dai, Xin^a | Long, Yongjun^a | Cao, Jiayong^{a; b} | Wang, Shigang^{a; *}

Affiliations: [a] School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China | [b] School of Mechanical Engineering, Shanghai Institute of Technology, Shanghai, China

Correspondence: [*] Corresponding author: Shigang Wang, School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Rd., Minhang District, Shanghai, China. E-mail:wangshigang@sjtu.edu.cn

Abstract: This paper presents a two-dimensional (2D) analytical model for predicting the magnetic field in field modulated permanent-magnet (PM) eddy-current couplings with a slotted conductor rotor. Based on the subdomain method, the original radial-flux model with a cylindrical geometry is simplified and analyzed in Cartesian coordinates to solve the moving conductor eddy current problem, avoiding the complicated computation with Bessel function in cylindrical or polar coordinates. In the process of modeling, the effects of the field modulation on the eddy currents, the influence of eddy current reaction field on the air gap field, and the interactions between the adjacent conducting bars are considered. The moving PM field is treated as a source of a time-harmonic field and the diffusion equations in the bars are simplified and converted to complex temporal Hemholtz functions. The comparison of analytical and nonlinear finite element analysis results shows the effectiveness of the proposed analytical model.

Keywords: Eddy current coupling, field modulation, radial flux

DOI: 10.3233/JAE-162135

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 3-4, pp. 1295-1303, 2016