Simulation on modified multi-surface levitation structure of superconducting magnetic bearing for flywheel energy storage system by H-formulation and Taguchi method

Abstract

Improving the performance of superconducting magnetic bearing (SMB) is very essential problem to heighten the energy storage capacity of flywheel energy storage devices which are built of components such as superconductor bulks, permanent magnets, flywheel, cooling system and so on. In this paper, three surfaces levitation-superconducting magnetic bearing (TSL-SMB) was simulated in two-dimensional axisymmetric system using H-formulation and Taguchi method. The system was worked by field cooling (FC) method. Taguchi-based L32(21×49) mixed orthogonal array was used to formulate the simulation plans for TSL-SMB, and effects of geometric parameters on levitation force in TSL-SMB was considered using Analysis of Variance (ANOVA). In the optimized TSL-SMB structure, there was no good difference whether the effect of concentric ring PMs with opposite polarization was included or not. Therefore, four surfaces levitation-superconducting magnetic bearing (FSL-SMB) as advanced multi-surface levitation system was presented to improve the performance of SMB. The simulation results in the FSL-SMB system showed that the gap between the stator and the rotor and levitation force per permanent magnet volume might be increased more than those of TSL-SMB system in the condition of same load capacity, this will contribute to improve the load capacity of SMB.