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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.
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Closed-form expressions for the magnetic fields of rectangular and circular finite-length solenoids and current loops
A summary of closed-form expressions for the magnetic fields produced by rectangular- and circular-shaped finite-length solenoids and current loops is provided altogether for easy reference. Each expression provides the magnetic field in all space, except locations where a current of infinitesimal thickness is considered to exist. The closed-form expression for the magnetic field of a rectangular-shaped finite-length solenoid is derived using the Biot–Savart law. Closed-form expressions for the magnetic fields of solenoids and current loops can be used to avoid approximations in analytical models and may reduce computation time in computer simulations.
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- Award ID(s):
- 1803047
- PAR ID:
- 10597443
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- AIP Advances
- Volume:
- 10
- Issue:
- 6
- ISSN:
- 2158-3226
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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