Magnetic circuit

About: Magnetic circuit is a research topic. Over the lifetime, 15707 publications have been published within this topic receiving 118099 citations.

A generalized dynamic circuit model of magnetic cores for low- and high-frequency applications. II. Circuit model formulation and implementation

Abstract: This paper describes the formulation and implementation of a generalized dynamic magnetic core circuit model suitable for both low- and high-frequency applications. The behavior of magnetic cores with any arbitrary flux waveforms is modeled by a simple ladder network consisting of nonlinear inductors and resistors. The nonlinear B-H loop and the hysteresis loss are incorporated in distributed nonideal inductors and calculated by the Preisach scalar model of magnetic hysteresis. The eddy current and anomalous losses are accounted for by the generalized nonlinear equivalent resistors reported in Part I of the paper. The transmission line modeling method is employed to solve the nonlinear state equations. Numerical aspects and software implementation of the model are discussed. The generalized model has been verified by simulations and measurements at both low- and high-frequency operations.

Optimum Design of Transverse Flux Linear Motor for Weight Reduction and Improvement Thrust Force Using Response Surface Methodology

Abstract: Permanent magnet (PM)-type transverse flux linear motors (TFLMs) are electromagnetic devices which can develop directly powerful linear motion. The unique configuration makes power of output higher than longitudinal motors, but also it makes characteristic analysis difficulties. This paper deals with an effective analysis of PM-type TFLM by 3-D equivalent magnetic circuit network method (EMCNM). This paper presents optimum design of PM-type TFLM to reduce the weight of the machine with the constraints of thrust and detent force using response surface methodology (RSM). RSM was well adapted to make the analytical model of the minimum weight with constraints of thrust and detent forces and enable the objective function to be easily created and a great deal of the time in computation to be saved. Therefore, it is expected that the proposed optimization procedure using RSM can be easily utilized to solve the optimization problem of electric machines.

Analysis of the Efficiency of Thin‐Film Magnetic Recording Heads

Abstract: Equations for the flux, magnetic field, and current distributions in a single‐turn planar magnetic recording head are derived making the assumption that the magnetic material has constant permeability. These equations are solved in the frequency domain and an expression is given for the head efficiency in terms of the head dimensions, permeability, and frequency.

AMR current measurement device

Abstract: Many devices for contactless current measurement employ a magnetic circuit (flux concentrator) formed by a ferromagnetic ring (or yoke) with the sensor (typically Hall element) placed in the air gap. Thus the impact of the ambient magnetic fields (i.e. other than caused by the measured current) is highly reduced and the sensitivity of the device is increased. However, the linearity of such measurement can be affected by the non-linear behavior of the magnetic material of the yoke. A device for the contactless current measurement with anisotropic magnetoresistive sensors (AMR) has been developed. As the AMRs are much more sensitive than classically used Hall sensors, no magnetic concentrator is needed. The realized device reaches so far the linearity error of ±0.05% in the current range of ±8 A, i.e. the absolute resolution is 4 mA.

Accurately modeling EI core inductors using a high-fidelity magnetic equivalent circuit approach

Abstract: We present a high-fidelity magnetic equivalent circuit (HFMEC) inductor model that reduces the inaccuracies associated with a traditional MEC approach. The model can accurately predict the flux linkage versus current characteristic in a fraction of the time needed for finite-element analysis. The accuracy, computational efficiency, and simple inputs (consisting of only geometry and material specifications) make the model ideal for automated inductor design.