Article

Electromagnetism

January 2015

DOI:10.4018/978-1-4666-8441-6.ch001

Authors:

For Direct Current machines, Electromagnetism serves as the core. Therefore, in this chapter, the authors provide the fundamental background to the reader by giving basic information regarding electromagnetism. The chapter starts by discussing system of units, then the authors discuss regarding magnetic field, intensity of magnetic field, flux, flux density, amperes law, and units of flux. After that the authors discuss theory of magnetism, law of electromagnetic induction, Fleming’s right and left hand rules, law of magnetic circuit, energy stored in a magnetic field and energy of inductive circuit. Hysteresis loop with core losses and hysteresis loss is then discussed. Finally, we discuss Eddy current loss.

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August 1915 · Transactions of the American Institute of Electrical Engineers

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October 2015 · Physica B Condensed Matter

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Article

Full-text available

Electromagnetic characterization of current transformer with toroidal core under sinusoidal conditio...

April 2016 · Physica B Condensed Matter

The aim of this paper is to present a new procedure for the electromagnetic analysis of a measuring current transformer under sinusoidal conditions in its electrical and magnetic circuit. The influence of the magnetic hysteresis has been taken into account using the measured inverse magnetization curve and phase lag between the time waveforms of the magnetic field and the magnetic induction. ... [Show full abstract] Using the proposed analysis, ratio and phase errors of the current transformer have been calculated. The results of the calculation have been compared with experimental results and a good agreement has been found.

Last Updated: 21 Nov 2024