A novel four degree-of-freedoms bearingless permanent magnet machine using modified cross feedback control scheme for flywheel energy storage systems

Article type: Research Article

Authors: Jin, Zhijia^a | Sun, Xiaodong^{a; b;} | Yang, Zebin^c | Wang, Shaohua^a | Chen, Long^{a; b} | Li, Ke^c

Affiliations: [a] School of Automobile and Traffic Engineering, Jiangsu University, Zhenjiang, China | [b] Automotive Engineering Research Institute, Jiangsu University, Zhenjiang, China | [c] School of Electrical and Information Engineering, Jiangsu University, Zhenjiang, China

Correspondence: [*] Corresponding author: Xiaodong Sun, Jiangsu University, Xuefu Road 301, Jingkou District, Zhenjiang, China. E-mail: xdsun@ujs.edu.cn

Abstract: In this paper, a novel bearingless permanent magnet machine (BPMM) without strong and complex magnetic field coupling, which can limit four degree-of-freedoms (DOFs) independently, is presented for the flywheel energy storage system (FESS). The proposed machine provides suspension force by means of interaction of flux density between the permanent magnet rings and the winding current. Afterwards, the structure parameters have been designed and the model of the proposed machine is derived. Meanwhile, based on the conventional cross feedback control, the modified control scheme with compensation for cross channels is illustrated. Additionally, combining with the machine model and modified cross feedback controller, the simulation is built to demonstrate the effectiveness. The results show the smaller fluctuation in steady state, fast response with disturbance and less impact on undisturbed channels by employing the modified control.

Keywords: Bearingless permanent magnet machine, suspension force, structure design, finite element analysis, cross feedback control

DOI: 10.3233/JAE-180115

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 60, no. 3, pp. 379-392, 2019