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This paper analyzes the damping and stiffness terms of a 4-degree of freedom laboratory scale electrodynamic wheel magnetic levitation vehicle. The vehicle creates both suspension and propulsion forces through the simultaneous rotation and translation of the electrodynamic wheels above a conductive non-magnetic plate of finite thickness. The stiffness and damping terms were derived using an analytic 3-D steady-state eddy current model, and are analyzed based on their suitability for a linear state-space model. The implications with respect to static stability are discussed.
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Examination of the Stiffness Terms needed to Model the Dynamics of an Eddy Current based Maglev Vehicle
This paper re-examines the basis for each eddy current stiffness term computed from prior published steady-state eddy current models. The paper corrects prior analysis work by confirming, through the use of 2-D and 3-D dynamic finite element analysis modelling, that when a magnetic source is moving over an infinite-wide and infinite-long conductive sheet guideway the steady-state lateral and translational stiffness terms will be zero and only the vertical coupled stiffness terms need to be modelled. Using these observations, a much simplified 6 degrees-of-freedom (DoF) linearized eddy current dynamic force model can be used to compute the steady-state force changes in eddy current based maglev vehicles when operating over a wide uniform conductive track.
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- Award ID(s):
- 1810489
- PAR ID:
- 10422736
- Date Published:
- Journal Name:
- IEEE transactions on magnetics
- ISSN:
- 0018-9464
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TMAG.2023.3287512
