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To understand the behavior of the magnetization processes in ferromagnetic materials in function of temperature, a temperature-dependent hysteresis model is necessary. This study aims to investigate how temperature can be accounted for in the energy-based hysteresis model, via an appropriate parameter identification and interpolation procedure.

The hysteresis model used for simulating the material response is energy-consistent and relies on thermodynamic principles. The material parameters have been identified by unidirectional alternating measurements, and the model has been tested for both simple and complex excitation waveforms. Measurements and simulations have been performed on a soft ferrite toroidal sample characterized in a wide temperature range.

The analysis shows that the model is able to represent accurately arbitrary excitation waveforms in function of temperature. The identification method used to determine the model parameters has proven its robustness: starting from simple excitation waveforms, the complex ones can be simulated precisely.

As parameters vary depending on temperature, a new parameter variation law in function of temperature has been proposed.

A complete static hysteresis model able to take the temperature into account is now available. The identification is quite simple and requires very few measurements at different temperatures.

The results suggest that it is possible to predict magnetization curves within the measured range, starting from a reduced set of measured data.

The purpose of this paper is to analyze the main assumption of a dynamic flux tube model and to define its rules of use.

The studied dynamic model lumps together all dynamic effects in the circuit by considering a single dynamic parameter. A physical meaning of this parameter as well as rules of use of the model are elaborated from analyses performed on several samples. A systematic comparison between experimental and calculated results allows to argue the conclusions.

The model gives accurate results when a weak heterogeneity of magnetic data exists, nevertheless, the saturation phenomenon enlarges the validity domain. By considering the losses separation assumption, the model allows to obtain separately an estimation of losses due to classical eddy currents and due to the wall motion effects.

The estimation of the model's parameter value is still empiric, a work is in progress on this subject.

The model's implementation in a flux tubes network allows to simulate the dynamic behaviour of industrial actuators having massive cores.

A physical interpretation of the parameter associated to the dynamic flux tube model is given. Rules of use of the model are also defined.