Core loss behavior in high frequency high power transformers—I: Effect of core topology

Abstract

This two-part paper presents an overview of core loss computations performed in both time and frequency domains in order to evaluate their behavior in single phase transformers with different core topologies. Moreover, the effects of non-sinusoidal waveforms on well-known core loss calculation methods are investigated with both analytically and finite element calculations. Three well-known configurations of transformers utilized in high frequency high power applications are investigated, namely, the core type, the shell type, and the matrix transformer. Based on the results obtained from a large number of FEM simulations for different operating conditions, the efficiencies of the transformers are compared in terms of distribution of magnetic flux density, loss density, total core loss, and weight. The analysis shows that for lower range of frequency and power, the shell type core could be the favorable option, and on the other hand, core type seems to be an appropriate solution for higher values of the operating frequency and nominal power. V C 2012 American Institute of Physics. [http://dx.

Design optimisation of an inductor‐integrated MF transformer for a high‐power isolated dual‐active‐bridge DC–DC converter

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Optimization and experimental validation of medium-frequency high power transformers in solid-state transformer applications

“…2, resulting in distinct transformer geometries corresponding to its set of free variables. Utilizing the modified and developed expressions, the core, windings and dielectric losses are then being evaluated for each set of free parameters [9], [10]. The efficiency, power density and temperature rise of each transformer are then extracted and compared in order to obtain the optimum combination that meets the requirements.…”

Design Methodology and Optimization of a Medium-Frequency Transformer for High-Power DC–DC Applications

“…Among all categories of magnetic materials which are suitable for high frequency applications, ferromagnetic materials are favored to be used in higher power density applications, due to their higher saturation flux densities than ferrites [14]- [16]. Particularly, amorphous and nanocrystalline materials are categorized as low loss and high saturation level ferromagnetic material [17], [18]. Therefore, Vitroperm500F is chosen as the magnetic material used in the current case study optimization.…”