Journal ArticleDOI
Effects of eddy currents in transformer windings
P.L. Dowell
- Vol. 113, Iss: 8, pp 1387-1394
TLDR
In this article, the effect of eddy currents on transformer windings is considered and a method is derived for calculating the variation of winding resistance and leakage inductance with frequency for transformers with single-layer, multilayer and sectionalised windings.Abstract:
The effects of eddy currents in transformer windings are considered, and a method is derived for calculating the variation of winding resistance and leakage inductance with frequency for transformers with single-layer, multilayer and sectionalised windings. The method consists in dividing the winding into portions, calculating the d.c. resistances and d.c. leakage inductances of each of these portions, and then multiplying the d.c. values by appropriate factors to obtain the corresponding a.c. values. These a.c. values are then referred to, say, the primary winding and summed to give the total winding resistance and leakage inductance of the transformer. Formulas are derived and quoted for calculating the d.c. resistances and leakage inductances of the winding portions. Theoretical expressions are derived for the variation with frequency etc. of the factors by which the d.c. values must be multiplied to obtain the corresponding a.c. values. These expressions are presented in the form of graphs, permitting the factors to be read as required.read more
Citations
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Optimal stray magnetic couplings for EMC filters
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Generalization of orthogonality principle to model solenoidal wound multiwinding transformers
TL;DR: In this paper, a generalization of the orthogonality principle is presented in order to increase model accuracy of the well known 1D-model for eddy current phenomena in multiwinding transformers with mixed conductor configurations consisting of foils, round wires and litz wire.
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Health monitoring of POL converter using digital PWM controller
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Proceedings ArticleDOI
Effective modeling of leakage inductance for use in circuit simulation
Peter R. Wilson,Andrew Brown +1 more
TL;DR: In this article, Dowell's well-known theoretical approach is tested using measurements and finite element analyses and the results presented show deficiencies in the accuracy of models generated using Dowell approach and highlight the trade-offs between model complexity, simulation time and accuracy when the finite element analysis method is applied.
Proceedings ArticleDOI
Optimal Design of a Highly Integrated Brushless Rotor Power Supply for Electrically-Excited Generators in Vehicle-Related Applications
TL;DR: In this paper, the substitution of slip rings through an inductive power transfer system for field winding supply in wound rotor synchronous generators is presented, where an analytical model of the inductive link as well as the compensation circuitry is presented.
References
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Journal ArticleDOI
Effective resistance to alternating currents of multilayer windings
Edward Bennett,Sidney C. Larson +1 more
TL;DR: In this article, a multilayer winding carrying an alternating current, such as the windings illustrated in figures 1, 2, and 3, each layer of copper lies in the alternating magnetic field set up by the current in all the other layers.
Journal ArticleDOI
Eddy Currents in Large Slot-Wound Conductors
TL;DR: In this article, the authors discuss the more important causes of eddy currents in heavy conductors carrying alternating currents and surrounded on three sides by iron, and propose a method to identify the most important causes.
Journal ArticleDOI
Effective Resistance to Alternating Currents of Multilayer Windings
Journal ArticleDOI
Eddy-Current Losses in Cylindrical Conductors, with Special Applications to the Alternating Current Resistances of Short Coils
TL;DR: In this article, it is shown that a considerable proportion of the effective resistance of inductive coils when used at radio frequencies is caused by the eddy-currents set up in the wires of the coils by the alternating magnetic field in which they are situated, and that in extreme cases the alternating current resistance may amount to more than one hundred times the direct current resistance.
Journal ArticleDOI
Heat Losses in the Conductors of Alternating-Current Machines
TL;DR: In this article, the authors show how hyperbolic functions of complex angles may be applied to the solution of the problem of heat losses in rectangular conductors that are embedded in open slots.