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In the last decade, various works have demonstrated that a class of artificial material called metamaterials (MTM) can synthesize mu-negative (MNG) media capable of evanescent-wave focusing which largely enhances the magnetic coupling between coils, which is the basic mechanism of Inductive Power Transmission (IPT) systems. In the present work, MTM-enhanced coupling in IPT systems is examined through analytical and numerical results, which are validated by experimental data. Adopting a transmission-line (TL) based approach to describe the general MTM-enhanced IPT system, it is evidenced that MNG MTMs can be interpreted as a negative impedance from a circuital point of view. [ABSTRACT FROM AUTHOR]

A complete modeling technique for unshielded power cables is proposed. The focus is on applications where the resonance phenomena take place in electrically long cables and is originated from periodic excitation, such as power converters. The resonance problems caused by switching converters tend to become more common with the advent of wide band gap semiconductors. This paper includes a new experimental protocol specific for unshielded power cable parameter identification in a wide frequency band, from DC up to medium frequencies (tens of MHz), with an impedance analyzer. It also introduces a frequency-domain simulation tool with conversion to the time domain, via the Fourier series. This frequency-domain modeling is straightforward, and its accuracy depends only on the accuracy of the cable parameter identification. [ABSTRACT FROM AUTHOR]

In the electromagnetic compatibility behavior of power electronic converters, parasitic magnetic couplings between components are one of the main causes of dysfunctions or poor filtering. These couplings may be either conducted or near-field interferences. To handle interaction problems, full knowledge of these magnetic couplings is essential. This paper is an overview of the work on near magnetic field interference undertaken in the last 15 years by the International Maxwell Laboratory. This paper details a predictive method that accurately and efficiently calculates near magnetic field coupling between two sources. The method uses near-field multipolar expansion in spherical harmonics of electromagnetic sources to determine close magnetic coupling between two sources from their equivalent models. This paper also shows how theoretical developments of large loop antennas have evolved from the van Veen antenna, a model with only two degrees of freedom, to a more complex model in terms of degrees, order, and types of harmonics. In parallel, it describes developments in the measurement method that provides input to the theoretical model. To illustrate how the research has evolved, we discuss coupling between two complex sources to assess the accuracy of this predictive method. [ABSTRACT FROM PUBLISHER]

This paper aims to present an evaluation of noncanonical mode stirred chambers, whose excitation is carried out by transmission lines. Many configurations are taken into account regarding the influence of the wire arrangement and their phase shift excitation on the field homogeneity. The simulations were carried out within the framework of finite integration technique (FIT) and transmission- line modeling (TLM) methods. Experimental and theoretical results are presented regarding the chamber suitability to electromagnetic compatibility (EMC) tests. It is emphasized the viability of extending the present standard frequency range recommendation to lower frequency values. [ABSTRACT FROM AUTHOR]

Focuses on a study which proposed the application of constrained decision planning in the optimization of lightning protection system (LPS). Assessment of the threshold levels of LPS when sample structure is struck by lightning; Discussion on time-domain simulation to analyze magnetic flux; Methodology and results.

Discusses transient induced voltage computation in a high building struck by lightning. Prediction of electromagnetic (EM) fields and their induced effects; Important aspects of the method used for evaluating the lightning induced voltage.