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The aim of this paper is to present a comprehensive approach to analyse and interpret power loss in ferromagnetic materials with particular attention devoted to excess power loss. Experimental results obtained with an Epstein frame and toroidal core made of electrical steel are presented in the paper, including quasistatic and dynamic hysteresis loops. According to the time waveforms of the measured magnetic field and magnetic flux density, an instantaneous power loss is calculated for the quasistatic and dynamic case. Moreover, the instantaneous power loss due to eddy current is calculated, as well as the instantaneous excess power loss and excess magnetic field. This excess magnetic field is compared to the excess magnetic field calculated by Bertotti’s model. Analysis and discussion of the results obtained is given in the paper.

The paper presents a new approach to modeling of magnetic properties and the influence of temperature on hysteresis loops in La(FeCoSi)13 magnetocaloric compound. The GRUCAD hysteresis model has been used for analysis of magnetic behavior in the vicinity of the magnetic phase transition. The modeling results are in a qualitative agreement with experiment.

The approach advanced by Harrison puts in the spotlight the fundamental role of bistability in hysteresis modeling. The description is based on physical premises concerning irreversible thermodynamics. In the original model, the upscaling of irreversible phenomena acting on the micromagnetic level is carried out by the introduction of a phenomenological parameter β. In the present paper, an alternative approach is proposed. The outputs of individual outputs of elementary hysteresis units (hysterons) are considered like in the stop model. A verification of the proposed model is carried out using measurement data for a praseodymium–dysprosium ribbon sample and a cylinder core made of cobalt-based amorphous material. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present a methodology for the calculation of the R-L parameters of a model of a nonlinear hysteretic inductor. The methodology is based on the analysis of the instantaneous magnetising power calculated from the hysteresis loop of the inductor and is completely developed in the time domain. The instantaneous magnetising power is firstly separated into the oscillatory and absorbed components. Thereafter, the parameter R is calculated using the absorbed component and the parameter L using the oscillatory component. The methodology is validated through the comparison of the results for parameters R and L obtained with the proposed method and the existing method based on the Poynting theorem. The validation is demonstrated on the specific simulated cases with idealised parameters of a nonlinear circuit. Additionally, the paper presents results for the parameters R and L calculated from the hysteresis loops measured at frequencies from 1 to 300 Hz. Furthermore, the fitting functions representing the variation of these parameters with the rate of change of magnetic flux density, and the corresponding results, are presented in the paper. A discussion of all the results presented and applicability of the methodology proposed, as well as the concluding remarks, are given thereafter. [ABSTRACT FROM AUTHOR]

The paper considers a qualitatively different behaviour of two phenomenological hysteresis models. The first one is the widespread Jiles-Atherton description, which is based on the ”effective field” concept. The other model is the proposal by the Brazilian research team GRUCAD. First order reversal curves simulated with the latter formalism do not exhibit negative slopes. This feature is in accordance with the experiment.

Magnetic properties of electrical steels, either grain-oriented or non-oriented ones, are significantly affected by anisotropy. The paper considers two descriptions for the dependence: power losses versus angle. The first one is based on the theoretical studies on texture from materials science. The other one is purely phenomenological, and based on an equation of ellipse in a rotated coordinate system.

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Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper presents a new approach to modeling of magnetic properties and the influence of temperature on hysteresis loops in La(FeCoSi)13 magnetocaloric compound. The GRUCAD hysteresis model has been used for analysis of magnetic behavior in the vicinity of the magnetic phase transition. The modeling results are in a qualitative agreement with experiment. [ABSTRACT FROM AUTHOR]