vector magnetization of a distribution of cubic particles

A model for the vector magnetization of a distribution of particles with cubic anisotropy is presented. Recent work by the authors modeled the vector magnetization of a distribution of uniaxial particles by decomposing the total magnetization into reversible and irreversible components. In this paper, using an energy approach applicable to a generic plane, the model is extended to include cubic anisotropy projected to the (100) plane. The magnitude of the irreversible component is modeled using a Preisach differential-equation approach; however, other valid models can be used. The direction of the reversible component is modeled using the minimum energy approach of the classical Stoner–Wohlfarth model and taking into account the anisotropy field. The formulation of the generalized model is derived and its results are discussed considering (i) oscillation and rotational modes, (ii) lag angle, and (iii) magnetization trajectories

Influence of Non-Linearity in Losses Estimation of Magnetic Components for DC-DC Converters

In this paper, the problem of estimating the core losses for inductive components is addressed. A novel methodology is applied to estimate the core losses of an inductor in a DC-DC converter in the time-domain. The methodology addresses both the non-linearity and dynamic behavior of the core magnetic material and the non-uniformity of the field distribution for the device geometry. The methodology is natively implemented using the LTSpice simulation environment and can be used to include an accurate behavioral model of the magnetic devices in a more complex lumped circuit. The methodology is compared against classic estimation techniques such as Steinmetz Equation and the improved Generalized Steinmetz Equation. The validation is performed on a practical DC-DC Buck converter, which was utilized to experimentally verify the results derived by a model suitable to estimate the inductor losses. Both simulation and experimental test confirm the accuracy of the proposed methodology. Thus, the proposed technique can be flexibly used both for direct core loss estimation and the realization of a subsystem able to simulate the realistic behavior of an inductor within a more complex lumped circuit

Electromagnetic Nondestructive Test (ENDT) Data Inversion by a Neural Network Approach

With this paper we aim at presenting a neural based approach to conductivity distribution reconstruction by eddy current (EC) data inversion

Design and Comparison of the Performance of 12-Pulse Rectifiers for Aerospace Applications

In this paper, a conventional 12-pulse transformer unit (CTU) and an autotransformer 12-pulse transformer unit (ATU) are compared in the view of the RTCA DO-160 standard for aircraft applications. The design of the magnetic components is proposed via a coupled FEM-circuital analysis in the time domain for an 800 Hz/2 kW system. Input AC distortion, power factor, and output DC ripple are evaluated through simulations. An accurate power loss analysis is carried out, taking into account copper losses, magnetic losses, and power losses due to power switches. The reduction in the size and weight of the ATU with respect to the CTU solution is discussed, including the need for filtering systems and the standard requirements