This paper presents a distributed current source (DCS) method for modeling the dynamic responses of eddy current density (ECD) induced in electrical conductors and its corresponding magnetic flux density (MFD); both nonmagnetic and weakly magnetized conductors are considered. Unlike conventional numerical methods such as finite element analysis (FEA), the DCS method, which accounts for the eddy-current and magnetization effects by means of equivalent volume and surface current-sources, derives closed-form solutions to the ECD and MFD fields in state-space representation. The model has been experimentally validated and verified by comparing results from FEA simulations with both harmonic and nonharmonic excitations. To gain physical insights to the measured MFD for simultaneous estimating the material/geometrical properties of a conductor, the static and dynamic responses to rectangular pulsed current excitations have been numerically investigated, confirming the feasibility and effectiveness of the measurement methods.
Distributed Current Source Method for Modeling Magnetic and Eddy-Current Fields Induced in Non-Ferrous Metallic Objects
This paper presents a new modeling method to determine the harmonic eddy-current (EC) field induced in a non-ferrous metal and its corresponding magnetic flux density (MFD) by an EC-based sensing system for geometrical measurements, which accounts for the boundary effects of the object. Modeled using a distributed current source (DCS) method in state-space representation, the EC field is formulated as a two-step constrained least-square (CLS) problem to solve for its real and imaginary parts. Two practical techniques to improve
the efficiency and accuracy of the EC solutions are illustrated; the first refines the DCS distribution based on the skin-depth effects, and the second takes advantages of commercial mesh-generation software to facilitate the modeling of EC induced in complex shaped objects. The DCS-based EC models are verified numerically by comparing computed results with 2D analytical axisymmetric solutions and commercial finite-element analysis (FEA), and evaluated experimentally with an EC sensor that measures the MFD generated by the induced EC in different materials and geometrical configurations.
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- Award ID(s):
- 1662700
- NSF-PAR ID:
- 10054245
- Date Published:
- Journal Name:
- IEEE/ASME Transactions on Mechatronics
- ISSN:
- 1083-4435
- Page Range / eLocation ID:
- 1 to 1
- 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/TMECH.2017.2771763
