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This paper presents a simple dynamic vector-play model to calculate the iron loss and describe the vector hysteresis behavior of a non-oriented (NO) electrical steel sheet (ESS) under 50 Hz rotating magnetic fields. Based on the iron loss separation theory, the proposed model is separated to the static hysteresis component and eddy current component. The static hysteresis component is constructed by vector play model, which is identified by using 1 Hz minor B – H loops. And two coefficients \omega x and \omega y are introduced to consider the anisotropic property of NO ESS and the excess loss of eddy-current component under 50 Hz magnetic field. The validity of the proposed dynamic vector hysteresis model is verified by comparing it with the experimental results under various 50 Hz magnetic field conditions. [ABSTRACT FROM AUTHOR]

This paper proposes an equivalent magnetic hysteresis (B–H) curve for magnetic multiscale problems of complex materials composed of electrical conductors separated by insulating material. The conventional method, which assigns equivalent material constants to each material, cannot properly express the local eddy current loss and the extra magnetic field derived from the local eddy current. To solve this problem, we derive the magnetic hysteresis curve from the volume-averaged magnetic flux density and the surface magnetic field in the micro-model, and apply this curve to the macro-model. The mesh number of the novel macro-model is reduced to around one-tenth that of the micro-model. Magnetic hysteresis is treated by a free energy magnetic hysteresis model, and the macro-model ignores electrical conductivity. The magnetic hysteresis curve and the numerically calculated losses are consistent in the micro- and macro-models. The proposed method well expresses the local eddy current phenomena. [ABSTRACT FROM AUTHOR]

This paper compares two different identification methods of a static rate-independent energy-based hysteresis model with regard to the dynamic hysteresis loop shape prediction when coupled to the parametric magnetodynamic lamination model. The values of hysteresis model parameters are determined solely based on the quasi-static major loop. A semiphysical approach identifying the reversible and irreversible field components independently and a purely mathematical scheme using a differential evolution optimization algorithm determining all parameters simultaneously are compared. Both variants of parameter identification are analyzed in terms of hysteresis loop shape prediction for quasi-static as well as dynamic loops. [ABSTRACT FROM AUTHOR]

Recent advances have been made into modeling the soft-magnetic materials using the surface charge model. Until now, the model has only been used to model the field outside the soft-magnetic material. To include the saturation in the future, the magnetic field inside the material should be known. In this paper, the model is used to calculate the field inside the material when three different shapes of boundaries are considered. Comparing the results with Finite Element Method shows that the differences in the air region are <1 mT and those in the soft-magnetic region are <4 mT. Larger discrepancies can, however, occur near the corner of the material. [ABSTRACT FROM AUTHOR]

An analysis method for characteristics calculation of electric machines is proposed in order to take the effects of eddy currents and hysteresis phenomenon in laminated cores into account. In the proposed method, both the effects of eddy currents and hysteresis phenomenon are expressed as reaction magnetic fields against the exciting field. These fields are determined by coupling the main electromagnetic field analysis that neglects the detailed structures of laminated cores, and 1-D time-stepping analysis along the thickness of electrical steel sheets. The validity of this coupling is confirmed by comparing the measured and calculated results of the core-material characteristics. The effects of the reaction field on the torque characteristics of rotating machines are also clarified. [ABSTRACT FROM AUTHOR]

The magnetic tunnel junction (MTJ) effect has been widely applied in information technology and has brought about many revolutionary products in the past decade. In the meantime, many research studies on linear magnetoresistive sensors based on MTJ have been published to improve their performance metrics, such as linear field range, sensitivity, hysteresis, and noise. Though the frequency response of high-speed magnetic reading has been researched, the performance and application of linear magnetoresistive sensors with bridge configuration for high-frequency sensing remain underexplored. In this paper, we proposed an equivalent impedance network model of packaged linear magnetoresistive sensors based on MTJ with Wheatstone bridge configuration, and derived the corresponding frequency-dependent performance model, considering the influences of the parasitic capacitances and the amplitude of the applied magnetic field. Our work shows that the frequency characteristics of linear magnetoresistive sensors are closely associated with their $RC$ time constants, which depends on their resistances and parasitic capacitances. The useful bandwidth of an MTJ linear sensor is also related to the amplitude of the applied magnetic field. The bandwidth changes negligibly with the varying magnetic field in the range of less than 30% of the saturation field, but increases rapidly when it exceeds 30% of the saturation field. [ABSTRACT FROM AUTHOR]