Thesis (Ph. D.)--Northwestern University, 1926. / Cover title: The slow acting relay; an investigation of Eddy current and magnetism during release ... Engineering bulletin 304. Bibliography: p. 39.

Thesis (Ph. D.)--Northwestern University, 1926. / Cover title: The slow acting relay; an investigation of Eddy current and magnetism during release ... Engineering bulletin 304. Bibliography: p. 39.

[No abstract available] / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

No description available.

No description available.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (M.E.)--University of Canterbury, 2009. / Typescript (photocopy). "November 2009." Includes bibliographical references (p. [120]-123). Also available via the World Wide Web.

Thesis (M.Phil.) - University of Queensland, 2004. / Includes bibliography.

Eddy current sensing has been successfully used in various applications from testing heat exchange tubes for nuclear power plants to assessing dielectric thickness on printed circuit boards. However, in civil infrastructures cosmetic or cementitious surface material often keeps the probe or reader coil from accessing conductive medium inside the structure, resulting in reduced coupling as the distance increases between the DUT (device under test) and probe. Thus, the direct application of existing eddy current sensing technique is not very useful to detect flaws in civil infrastructures. To address this weak coupling problem, a simple scheme is proposed in which a resonant passive repeater tag is placed between the reader coil and the conducting test target. The feasibility of detecting defects like cracks or fractures in conductive medium using a passive resonant tag and measuring the impedance as a method of interrogation is shown. The electromagnetic waves are transmitted into and detected from a resonant tag and the conductive medium underneath the tag without direct physical contact using a reader coil above the resonant repeater tag. Experimental data taken from simple setups to demonstrate the advantage of the proposed scheme are presented. In addition, the theoretical background, such as the self and mutual inductance, and image theory, are discussed extensively. It is also shown that the theories can be applicable to build the equivalent circuit with the proper calibration process. The analyses have been carried out to characterize the responses resulting from the various experiments. Furthermore, new measurands, the effective normalized inductance and resistance, were devised and employed to reanalyze the same experimental data. An effort to construct equivalent circuit model of the system has been made to correctly predict the response without the actual experiment. To improve the process of building the equivalent circuit, the total 4 types of tags and 6 types of DUT are built and tested. The analysis is also given for the constructed equivalent circuit model.

M.Ing (Electrical and Electronic Science) / High frequency magnetic components have significant advantages related to cost and physical size compared to their low frequency counterparts. The advent of high frequency power switch technology made the transformer frequency a variable and recent advances in this field have been ever pushing the switching frequency of higher power converters. Although high frequency inductors and transformers have been used and applied extensively to an increasingly broad range of applications over recent decades, analysis and design of these devices involves certain difficulties, related to extra losses due to eddy currents as well as smaller cooling surfaces, to the developer and designer. Numerical simulations of eddy currents in windings are slow, if not impossible in many cases, due to the large mesh impositions required in order to converge. Eddy currents and thermal constraints impose limitations on flux- and current densities, complicating the design. As yet, a convenient means of design, analysis and optimization of the physical magnetic topology does not exist. In this study, a method for analysing eddy currents in windings, usmg a combined analytical and numerical approach, is presented and implemented in a CAD tool. The one dimensional solutions for eddy currents in strip conductors are written in a more flexible form. A new approach to magnetic component design, called scant modelling, is presented and applied to two practical examples. The scant model comprises a minimum number of functional and form parameters in analysing and optimizing a design, but considers eddy current effects, thermal constraints and the effects of physical size and shape of core and windings at high frequencies.