Vybrané modely magnetické hystereze

Abstract

The subject of this thesis is to study selected models of ferromagnetic hysteresis and apply them to properly chosen materials. A literature search was conducted, and an overview of models was compiled. The main focus is on the Jiles-Atherton model and FORC diagrams. Inconsistencies found in the Jiles-Atherton model led to the proposal of a new differential isotropic model of ferromagnetic hysteresis (DIMFH). To describe the ferromagnetic behaviour of materials, the assumption of the existence of magnetic clusters was proposed. Three modifications of Jiles-Atherton model and DIMFH were applied to the experimental data and the models were compared with each other. A user-friendly MATLAB code was created to determine the parameters of the models. An analysis of the freely available doFORC program was performed with an emphasis on possible program settings and noise suppression.