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Presents a study that examined two-dimensional finite-element and analytic calculation of eddy-current losses in thin linear conductors. Eddy-current losses for thick conductors; Comparison between the analytic and the finite-element-method; Conclusion.

This paper presents a 3-D finite element formulation for a skin depth-independent shell element. With this formulation, thin conducting shells, which are multiply connected (i.e., having holes), and which can be coupled with an external circuit, can be modeled. This formulation takes into account the field variation through the depth due to skin effect. First, the method is described. Next, three numerical examples, including an automotive example, are presented. [ABSTRACT FROM PUBLISHER]

In order to compute eddy current distributions in thin conductive nonmagnetic shells, a new integral formulation is proposed. The method is based on a surface impedance condition which takes into account the field variation through depth due to skin effect. It is general and enables the modeling of various problems whatever their skin-depth and avoiding the meshing of the air region. [ABSTRACT FROM PUBLISHER]

In order to improve the finite-element modeling of macroscopic eddy currents (associated with motion and/or a time-varying electrical excitation), an original error criterion for adaptive meshing, based on a local power conservation, is proposed. Then, the importance of the order element in the error computation is investigated. Finally, the criterion is coupled to a "bubble" mesh generator, and an adaptive meshing of a 2-D induction heating case is performed. [ABSTRACT FROM AUTHOR]

In this paper, we consider taking both microscopic excess and macroscopic classical induced losses and damping, occurring within bulk and laminated soft magnetic materials, into account. We will not detail actual eddy currents distributions but use homogenizing techniques and variational principles to derive a dedicated formulation with respect to the reduced magnetic vector potential AM, and still including specific material dynamic properties. At last, some 2-D computations are carried out and first results are discussed. [ABSTRACT FROM AUTHOR]

High frequency electrical machine modeling based on lumped parameter equivalent circuit requires that eddy currents effects be taken into account for 11 and L coefficient derivation. Substituting hysteretic materials (complex permeability) to conductive materials makes it possible to accurately approximate proximity losses and shielding effect while considering realistic meshes for finite element methods computation. Three-dimensional magnetodynamic simulations of transformer test-cases using anisotropic complex permeability for magnetic core and windings have shown a good agreement with the standard models results. [ABSTRACT FROM AUTHOR]

Presents a study which focused on T-T0-phi formulation for modeling coupled problem of three-dimensional eddy current and electrical circuit. Presentation of the problem; Relation between global current and voltage; Conclusions.

Abstract: So as to fuse dynamic magnetization properties of soft materials with the electromagnetism theory, we investigate the inclusion of microscopic reversal processes related to domains and walls in macroscopic Maxwell equations. We first introduce a model for independent walls and the unidirectional motion mechanism; then we characterize one sample with measurements and analytical calculations in case of one-dimensional linear problems. [Copyright &y& Elsevier]