Title :
Modeling the 3-D Rotational and Translational Motion of a Halbach Rotor Above a Split-Sheet Guideway
Author :
Bird, Jonathan ; Lipo, Thomas A.
Author_Institution :
Univ. of North Carolina, Charlotte, NC, USA
Abstract :
When a Halbach rotor is simultaneously rotated and translationally moved above a split-sheet aluminum guideway a traveling time-varying magnetic field is created in the air gap. This field induces eddy currents in the guideway that can simultaneously create suspension and propulsion forces. If the rotor is offset from the center then a re-centering guidance force can also be created. As the forces are created in a highly inductive way the use of magnets circumvents any low power factor issues and enables a relatively high lift-to-weight ratio to be attained in comparison to using windings. The conductive and nonconductive regions are modeled by using a steady-state convective A-phi formulation. The Halbach rotor is modeled using a 3-D analytic based model and is coupled to the conductive guideway region using boundary conditions. The steady-state rotation of the Halbach rotor is modeled by incorporating complex terms in the analytic model. The accuracy of the steady-state model is confirmed by comparing it with a 3-D transient finite-element magsoft flux model (with no translation) and with experimental results (with both rotation and translation). The effect of the rotor width on performance is also investigated.
Keywords :
air gaps; eddy currents; finite element analysis; power factor; rotors; 3D analytic based model; 3D rotational modelling; 3D transient finite-element magsoft flux model; Halbach rotor; air gap; eddy currents; guidance force; high lift-to-weight ratio; low power factor; magnetic field; propulsion forces; split-sheet aluminum guideway; steady-state convective A-phi formulation; suspension; translational motion modelling; Biot–Savart law; Halbach rotor; convective; diffusive; eddy currents; finite-element method; maglev;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2009.2021160