Two-dimensional Vector Hysteresis Characteristics Modeling Of The Magnetic Materials In Electrical Engineering

According to the requirements of the key project supported by the Natural Science Foundation of China, two-dimensional(2-D) vector hysteresis characteristics theory and application of the magnetic materials are carried out in this thesis. To begin with, a novel vector hysteron is defined based on the theory of classical hysteresis models. Then, a 2-D vector magnetic hysteresis model is established by combining the classical hysteresis models with the previous vector magnetic hysteresis operator. Furthermore, the availability and practicality of the hysteresis model are verified by analyzing the magnetization process of magnetic materials under different excitation. This study can provide theoretical guidance for the tensor magnetic hysteresis properties of the magnetic materials in electrical engineering. The main research contents are as follows:1. The modeling method of hybrid vector hysteresis model based on the classical Preisach model and Stoner-Wohlfarth(S-W) model is proposed. Based on the conditions of single domain uniaxial anisotropy of magnetic particles in the magnetic steady state, vector magnetic equipotential line equation of the magnetized magnetic particles is deduced, which paves the theoretical foundation for the definition of two-dimensional vector hysteresis operator.2. In terms of the magnetic energy points, magnetization characteristics of a single magnetic particle is qualitatively analyzed. The critical surface equations of hysteron are established by means of the equipotential curves of magnetic particles magnetic field, so that the hysteron is defined as a closed region in the applied field plane. The determination of magnetization direction of hysteron and the effect of interaction field on the critical surface equations are also discussed in detail. Availability of the hysteron is verified by analyzing its magnetic properties.3. Numerical simulation of the hysteresis characteristics for single hysteron under different excitation is achieved by calculating the magnetization process of magnetic materials under alternating and rotational excitation magnetic field. The impact factors,which would affect the simulation results of magnetic hysteresis property of the hysteron, are also discussed systematically. The density function of hysteron in the applied field plane was also presented.4. Based on the vector magnetic hysteresis operator defined previously, a 2-D vector magnetic hysteresis model was established. The magnetization process of hysteresis models that consist of anisotropy or isotropy hysteron are calculated and analyzed under the alternating and rotational excitation. Meanwhile, the vector hysteresis magnetic characteristics modeling of the magnetic materials is initially realized.5. The 2-D vector magnetic hysteresis model is built for soft magnetic composite(SMC) materials. And the hysteresis characteristics of the SMC materials under the condition of sinusoidal alternating and circular rotating excitation magnetic field are modeled by using the new hysteresis model. Comparisons between the simulation and experimental results show that the hysteresis model can efficiently simulate the hysteresis characteristics of SMC materials under middle or lower excitation magnetic field.