Impact of the fringing effect on temperature distribution in windings and physical properties of toroidal ferrite inductors with a dual air gap

• Autorzy: Kasikowski R.
• Języki publikacji: EN

Abstrakty

EN

This paper examines the impact of the fringing field at an air gap on the temperature distribution, power loss and other properties of toroidal ferrite inductors with a dual air gap. An air gap constitutes a discontinuity in a magnetic path of an inductor, representing significantly greater reluctance to magnetic flux than that of a ferrite core. The magnetic flux does not cross the air gap in straight lines, but fringes out into the surrounding medium causing electromagnetic interactions with the copper winding enclosing the air gap. This phenomenon is a function of the air gap and the windings geometry as well as the operating frequency. The net effect of the fringing flux is to shorten the gap and to decrease the effective reluctance of the magnetic path. Consequently, coils wound on magnetic cores with a relatively large single air gap, thus with an exacerbated fringing effect, exhibit higher inductance than those with multiple, quasi-distributed or distributed air gaps of the same effective length as the discrete one. The presented research investigates the effects of splitting a discrete air gap on the electromagnetic and thermal properties of toroidal ferrite inductors.

Słowa kluczowe

EN

fringing effect; ferrite inductors; IR thermography; fringing-effect factor; power losses

• Wydawca: Wydawnictwo PAK
• Czasopismo: Measurement Automation Monitoring
• Rocznik: 2017
• Tom: Vol. 63, No. 4
• Strony: 135--138
• Opis fizyczny: Bibliogr. 9 poz., rys., tab., wykr., wzory

Twórcy

autor

Kasikowski R.

• Stadium Stontronics, Norwich Research Park, Norwich, United Kingdom
• Institute of Electronics, Lodz University of Technology, 211/215 Wólczańska St., 90-924 Łódź

Bibliografia

• [1] Jee-Hoon Jung, Jong-Moon Choi, Joong-Gi Kwon: Design Methodology for Transformers Including Integrated and Center-tapped Structures for LLC Resonant Converters. Journal of Power Electronics, Vol. 9, No. 2, March 2009.
• [2] Kenneth L. Kaiser: Electromagnetic Compatibility Handbook. CRC Press, 2005, p. 16-56.
• [3] Ericson R. W., Maksimovic D.: Fundamentals of Power Electronics, Springer Science+Business Media, 2001, p. 506-522.
• [4] Dowell P. L., “Effects of eddy currents in transformer windings”, IEE Proceeding 1966.
• [5] Kasikowski R., Więcek B., Farrer M.: Thermographic measurement and thermal modelling of air gap inductors in H-F power forward converters. 13th Quantitative InfraRed Thermography Conference, qirt.2016.053.
• [6] Kasikowski R., Więcek B., J. Gołaszewski J., Farrer M., Thermal Characterization of High-Frequency Flyback Power Transformer Measurement Automation Monitoring, Jun. 2015, vol. 61, no. 06.
• [7] Ferroxcube Data Handbook: Soft Ferrites and Accessories, 2009, p.1033.
• [8] Colonel Wm. McLyman T.: Transformer and Inductor Design Handbook, Fourth Edition, CRC Press, 2011, ISBN 9781439836880.
• [9] Kazimierczuk M. K.: High-Frequency Magnetic Components, John Wiley &Sons (2014), p. 54.

Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).