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
More filters
Journal ArticleDOI
Calculation method of winding eddy-current losses for high-voltage direct current converter transformers
TL;DR: In this paper, a correction method is introduced to make a more accurate calculation of winding eddy-current losses of high-voltage direct current (HVDC) converter transformer.
Journal ArticleDOI
Electromagnetic considerations in power electronic converters
P.D. Evans,B. Heffernan +1 more
TL;DR: A circuit example of a half-bridge series-parallel resonant converter working between 1-2 MHz and implemented using hybrid technologies is used to demonstrate how circuit, component and layout design are electromagnetically interdependent.
Proceedings ArticleDOI
Practical issues when calculating AC losses for magnetic devices in PCB implementations
TL;DR: In this paper, a method to calculate the ac losses (including skin effect and proximity losses) in planar magnetic devices having rectangular cross-section conductors is presented, which is based on the superposition of different losses in the wire (conduction and proximity) and also in an orthogonal decomposition of the field where the conductors are immersed.
Journal ArticleDOI
Optimal Stray Magnetic Couplings for EMC Filters
TL;DR: In this article, a PEEC model of an electromagnetic compatibility (EMC) filter is presented, including the discrete components as well as the interconnection models, including all magnetic stray elements (inductance and couplings).
Journal ArticleDOI
Design of high-efficiency non-insulated step-up converters
Luigi Schirone,Michele Macellari +1 more
TL;DR: The design techniques of high-efficiency non-insulated step-up converters were upgraded on the basis of a comprehensive model of power losses, also including several feeble effects whose contribution, although overshadowed at large power by conduction and switching losses, is relevant in the low-power regime and at the maximum power point.
References
More filters
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.