Design of a new structure passive magnetic bearing with radial magnetization using FEM

摘要

This paper investigates a new structure of passive magnetic bearings (PMB) that includes three ring shaped permanent magnets which can increase safety and accuracy in holding rotor in its correct position with greater force and stiffness amplitude. According to the axial symmetry around the z-axis in the structure of PMB, it is modeled using two-dimensional finite-element method (2D-FEM). Using this approximation, it becomes possible to calculate magnetic force and stiffness in the minimum computation time than three-dimensional finite-element method (3D-FEM). Sensitivity analysis is done to achieve the best configuration of new structure. Also it investigates prevalent structure of PMB that includes two ring shaped permanent magnets. A good comparison for the force and stiffness amplitude is done between previous structure and proposed structure by FEM. By considering force density as a reference, two structures are compared for the financial matters.