Finite Element Analysis-Based Modeling and Feedback Linearizing Control of a Large Air Gap Magnetic Levitator

2018 ◽  
Author(s):  
Samuel R. Miller ◽  
Gregory D. Buckner
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Control Strategies ◽  
Magnetic Bearing ◽  
Air Gap ◽  
Tracking Performance ◽  
Control Synthesis ◽  
State Equations ◽  
Catheter Position ◽  
Element Analysis

This paper summarizes a finite element analysis (FEA)-based modeling approach and nonlinear control synthesis for a large air gap magnetic levitator. The levitator consists of a 10 mm diameter heteropolar magnetic bearing used to control the position a 2 mm diameter ferromagnetic collar bonded to a flexible microcatheter. The unusually large air gap causes the system to exhibit strongly nonlinear behavior, which is attributed to significant leakage and mutual magnetic flux paths. FEA is used to model these nonlinear flux relationships and derive system state equations. Next, a feedback linearizing controller is designed, and closed-loop system simulations are performed using MATLAB. These simulations demonstrate stability and excellent tracking performance over a range of catheter positions. Steady-state performance is shown to depend on catheter position, with errors of up to 0.1760 mm in response to a 3 mm step input. The time-averaged error in tracking a 3 mm diameter circle is shown to be at most 0.0170 mm. Control strategies which are more robust to model uncertainties and discrepancies are recommended to improve the tracking performance.

scholarly journals Dynamic characteristics of triaxial active control magnetic bearing with asymmetric structure

Open Physics ◽  
2018 ◽  
Vol 16 (1) ◽  
pp. 9-13 ◽  
Author(s):  
Atsushi Nakajima ◽  
Katsuhiro Hirata ◽  
Noboru Niguchi ◽  
Masayuki Kato
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Active Control ◽  
Dynamic Characteristics ◽  
Negative Pressure ◽  
Axial Direction ◽  
Magnetic Bearing ◽  
Magnetic Bearings ◽  
Asymmetric Structure ◽  
Element Analysis

Abstract Supporting forces of magnetic bearings are lower than those of mechanical bearings. In order to solve these problems, this paper proposes a new three-axis active control magnetic bearing (3-axis AMB) with an asymmetric structure where its rotor is attracted only in one axial direction due to a negative pressure of fluid. Our proposed 3-axis AMB can generate a large suspension force in one axial direction due to the asymmetric structure. The performances of our proposed 3-axis AMB are computed through 3-D finite element analysis.

Finite Element Analysis and Dynamics Charateristic Study for High-Speed Magnetic Suspension Motorized Spindle of CNC Machine Tools

2011 ◽  
Vol 317-319 ◽  
pp. 595-599
Author(s):  
Yu Xin Sun ◽  
Ling Ding ◽  
Tao Shi ◽  
Xian Xing Liu
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Induction Motor ◽  
High Speed ◽  
Magnetic Bearing ◽  
Magnetic Suspension ◽  
Distinct Advantage ◽  
Motorized Spindle ◽  
Element Analysis ◽  
Spindle System

According to magnetic suspension motorized spindle system, high speed motorized spindle system based on bearingless induction motor is presented in this paper. The prototype of high speed motorized spindle system with bearingless induction motor is studied and analyzed by using finite element analysis software Ansoft/Maxwell and Riccati transfer matrix method, and compared with high speed motorized spindle system supported by Active Magnetic Bearing (AMB). The results show that high speed motorized spindle system with bearingless induction motor has distinct advantage of simple and compact structure, which is easier to realize high speed and extra-high speed operation.

Analysis of Design Parameter Sensitivity of On-Off Shift Solenoid Valve

2014 ◽  
Vol 998-999 ◽  
pp. 582-586 ◽  
Author(s):  
Fei Huang ◽  
Chun Yang Wang ◽  
Yu Bo Sun
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Electromagnetic Force ◽  
Orthogonal Experiment ◽  
Solenoid Valve ◽  
Air Gap ◽  
Design Parameters ◽  
Analysis Software ◽  
Element Analysis ◽  
Orthogonal Experiment Design

The parameters of the On-off shift solenoid valve are analyzed by finite element analysis software Ansoft and orthogonal experiment design. What’s more, the design parameters of the on-off shift solenoid valve can be optimized by analysis of the data of the orthogonal table. The result shows that the voltage influences the electromagnetic force the most, the air gap comes second and the number of turns is the minimum. We find that the force increases with the growth of voltage and the number of turns, but it is opposite to the air gap.

The Analysis of Radial Magnetic Bearing’s Magnetic Field in Active Magnetic Bearing Electric Spindle Unit

2011 ◽  
Vol 291-294 ◽  
pp. 1593-1599
Author(s):  
Ping Liao ◽  
Su Yang Ma ◽  
Guo Qing Wu ◽  
Jing Feng Mao ◽  
An Dong Jiang
Keyword(s):  
Magnetic Field ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Principal Axis ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
Affecting Factors ◽  
Element Analysis ◽  
Bearing Unit ◽  
Spindle Unit

Introduced the working principle of active magnetic bearing unit and took the electric spindle with 5.5kW for example, finite element analysis of the magnetic fields of radical magnetic bearing was analyzed through finite element analysis by ANSYS software to find out the variation of magnetic field distribution and affecting factors. Analysis results showed that radical magnetic bearing had small leakage magnetic field, the principal axis’ maximum offset from the ideal center line was 0.0025mm and the principal axis had superior radical running accuracy when the circularity of supporting journal on principal axis was 0.003mm, the unilateral air-gap value was 0.3mm while the principal axis suspended normally and the inside track’ circularity of magnetic pole was 0.007mm. It can meet the working requirements of precision machine tool. The research results provided theoretical basis for structural optimization of the active magnetic bearing unit.

A Nonlinear Magnetic Circuit Analysis of a Permanent Magnet Biased Homopolar Bearing

1999 ◽  
Author(s):  
Andrew Kenny ◽  
Alan Palazzolo
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Permanent Magnet ◽  
Analytical Methods ◽  
Magnetic Circuit ◽  
Three Dimensional ◽  
Magnetic Bearing ◽  
Axial Flux ◽  
Element Analysis ◽  
Good Agreement

Abstract A magnetic circuit model for a homopolar magnetic bearing is presented. This model connects the fore and aft circumferential flux paths with axial flux paths through the rotor and back iron. The bias flux is provided by a circumferential permanent magnet in the back iron. Results for an analysis using the nonlinear Hyperco50 B-H curve are presented. These results are compared to the results of a three dimensional magnetostatic finite element analysis. The two analytical methods are in good agreement and show that the control flux in this type of bearing follows both circumferential and axial paths.

Sign in / Sign up

Export Citation Format

Share Document