Modeling of Pulsed Transformer with Nanocrystalline Cores

Subject Areas : Renewable energy

Amir Baktash ¹ , Abolfazl Vahedi ²

1 - Iran University of Science & Technology
2 - Iran University of Science & Technology

Received: 2014-03-30 Accepted : 2014-08-03 Published : 2014-09-01

Keywords: Hysteresis loop model, Nanocrystalline materials, reluctance networks method, series resonant converter, tape wound core,

Abstract :

Recently tape wound cores, due to their excellent properties, are widely used in transformers for pulsed or high frequency applications. The spiral structure of these cores affects the flux distribution inside the core and causes complication of the magnetic analysis and consequently the circuit analysis. In this paper, a model based on reluctance networks method is used to analyze the magnetic flux in toroidal wound cores and losses calculation. A Preisach based hysteresis model is included in the model to consider the nonlinear characteristic of the core. Magnetic losses are calculated by having the flux density in different points of the core and using the hysteresis model. A transformer for using in a series resonant converter is modeled and implemented. The modeling results are compared with experimental measurements and FEM results to evaluate the validity of the model. Comparisons show the accuracy of the model besides its simplicity and fast convergence.

References:

[1] S. Zurek, F. Al-Naemi, A.J. Moses, “Finite-element modeling and measurements of flux and eddy current distribution in toroidal cores wound from electrical steel”, IEEE Trans. on Magn., Vol. 44, No. 6, pp. 902-905, 2008.

[2] T. Nakata, N. Takahashi, K. Fujiwara, M. Nakano, “Analysis of flux and eddy current distributions in wound cores and experiments”, Trans. on Engineering Sciences, Vol. 11, pp. 255-264, 1996.

[3] G. Loizosa, T. Kefalasb, A. Kladasb, T. Souflarisa, D. Paparigas, “Flux distribution in single phase, Si–Fe, wound transformer cores”, Journal of Magnetism and Magnetic Materials, Vol. 320, No. 20, pp. 874-877, 2008.

[4] I. Hernandez, F. de Leon, J. M. Canedo, J.C. Olivares-Galvan, “Modeling transformer core joints using Gaussian models for the magnetic flux density and permeability”, IET Electr. Power Appl., Vol. 4, No. 9, pp. 761–771, 2010.

[5] J. Turowski, “Reluctance Networks”, in Sykulski, J. K., Computational Magnetics, Springer, Netherlands, pp. 145-164, 1995.

[6] C.R. Lines, W.A. Cronje, B. Wigdorowitz, “Extended 2D magnetic equivalent circuit method”, COMPEL, Vol. 29, No. 6, pp. 1435-1443, 2010.

[7] A. Ibala, A. Masmoudi, G. Atkinson, A.G. Jack, “On the modeling of a TFPM by reluctance network including the saturation effect with emphasis on the leakage fluxes”, COMPEL, Vol. 30, No. 1, pp. 151-171, 2011.

[8] V. Basso, “Hysteresis models for magnetization by domain wall motion”, IEEE Trans. Magn., Vol. 34, pp. 2207–2212, 1998.

[9] P. Nakmahachalasint, K.D. T. Ngo, L. Vu-Quoc, “A Static hysteresis model for power ferrites”, IEEE Transactions on Power Electronics, Vol. 17, No. 4, pp. 453-460, 2002.

[10] P. Nakmahachalasint, K.D. T. Ngo, L. Vu-Quoc, “A behavioral model for frequency-dependent hysteresis in power ferrites”, IEEE Transactions on Magnetics, Vol. 40, No. 4, pp. 1784-1790, 2004.

[11] “Nano-crystalline: A special product announcement”, MK Magnetics, 2007, available at: http://www.mkmagnetics.com/dataSheets/pdf/mkm-nanoCurves.pdf.

[12] A. Baktash, A. Vahedi, “Calculation of parasitic elements in Toroidal core transformers,” IEEE Trans. on Plasma Science, Vol. 42, No. 6, pp. 1690 - 1696, 2014.