A Study on the Design Procedure of the Eight Pole Magnetic Bearings for the Inner-rotor and the Outer-rotor Type

Abstract

-This paper presents design procedure of the magnetic bearings used for high-speed electric machines and flywheel energy storage systems. Magnetic bearing can be categorized by innerrotor type and outer-rotor type according to the position of the rotary disc. These two types are applicable based on application environments such as application space, required attraction force, and controllability. Magnetic bearing is generally designed based on the ratio (geometrical coefficient or geometrical efficiency) of pole width to rotor journal radius but proper ratio is only decided by the analysis. This is the difficulty of the magnetic bearing design. In this paper, proper design technology of the inner-rotor type and outer-rotor-type eight pole magnetic bearings is introduced and compared with the FEM analysis results, which verifies the proposed design procedure is suitable to be applied to the design of the magnetic bearings for the industrial applications and flywheel energy storage system

Analysis and design method of a combined radial–axial magnetic bearing based on asymmetric factor

“…Therefore, it has a lot of many advantages, such as no contact, no friction, no lubrication, low noise, active control and so on. It has been widely applied in many areas [1][2][3][4][5][6][7]. Usually, one axial bearing and two radial bearings are used to realise five degrees of freedom (DOFs) suspension [8][9][10][11][12][13].…”

2D analytical model for heteropolar active magnetic bearings considering eccentricity

“…In addition, the influence of the design parameters such as geometry, magnetisation, and stacking number on maximum material utilisation has been studied. In [5], the design procedure for two types of eight‐pole magnetic bearings, an inner rotor and an outer rotor, has been proposed by using finite‐element method (FEM). An analytical model of permanent magnetic bearings based on Halbach array with arbitrary segmented magnetised angle has been presented in [6].…”

Active Vibration Control of a Flexible Rotor by Flexibly Mounted Internal-Stator Magnetic Actuators

“…A limited number of authors have considered concepts whereby the magnetic bearing stator is located inside of a hollow rotor, for example in energy storage flywheels and bearingless and high-speed motors [25,26,27,28,29]. However, it is still generally considered that the AMB stator is rigidly located to the machine base.…”