Abstract
An analytical analysis of eddy current effects in nonlinear ferromagnetic materials in the presence of a supplementary dc magnetic field is presented. It seems that such a combination of exitation magnetic fields can be used to control the value of the eddy current impedance employed as an induction motor starter or as a dc current sensor. Moreover, this situation can be present in transformers and chokes connected with rectifier, inverter, or converter circuits. The analysis is for a one-dimensional configuration, a semiinfinite plate magnetized homogeneously in a direction parallel to its surface. The nonlinear magnetization characteristic of the ferromagnetic plate material is assumed to be of a step-function form. Solutions of the electric field intensity on the plate surface, the penetration depth of eddy currents in the plate, the eddy current losses, and surface impedance in the presence of a dc magnetic field are obtained. A connection is found between the values obtained in simultaneous dc and ac magnetization conditions and the values obtained in the case of only ac magnetic field excitation. As a result, it seems that the present analysis can be useful in estimating the eddy current effects produced in various configurations of nonlinear ferromagnetic materials by a simultaneous excitation of dc and ac magnetic fields through use of the extensive data concerning eddy current effects produced by only ac magnetic fields.
Original language | English |
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Pages (from-to) | 3704-3709 |
Number of pages | 6 |
Journal | IEEE Transactions on Magnetics |
Volume | 27 |
Issue number | 4 |
DOIs | |
State | Published - 1 Jan 1991 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering