Related Experiment Video

Updated: Jan 19, 2026

Eddy Currents

Eddy Currents

Numerical modelling of magnetic characteristics of ferrite core taking account of both eddy current and displacement

Mohendro Kumar Ghosh¹, Yanhui Gao¹, Hiroshi Dozono¹

¹Department of Electrical and Electronic Engineering, Saga University, Saga 840-8502, Japan.

|September 10, 2019

Abstract:

In the magnetic field analysis of magnetic devices using a ferrite core, such as a pulse transformer, the frequency-domain analysis is often carried out using the measured complex permeability under different frequency range. However, the nonlinear magnetic characteristics cannot be considered in the frequency-domain analysis because of the harmonics caused by it cannot be represented. The nonlinear magnetic characteristics can be considered in the time-domain analysis, but suitable constant conductivity and permittivity taking account of the microstructure of ferrite core, which can represent the measured complex permeability under different frequencies, needs to be investigated for the time-domain analysis. In this paper, the effective permeability of a toroidal ferrite core is tried to be demonstrated by using the linear ac steady state magnetic field analysis taking account eddy currents and displacement currents. It is shown that the measured permeability can be realized roughly by using the modified constant conductivity and permittivity. The nonlinear time-domain magnetic field analysis can be carried out using the modified constant conductivity and permittivity obtained from this paper.

Keywords:

Complex permeability Displacement current Eddy current Electromagnetism Ferrite core Magnetic field analysis

More Related Videos

Displacement Current

Displacement Current

Quantifying the Relative Thickness of Conductive Ferromagnetic Materials Using Detector Coil-Based Pulsed Eddy Current Sensors

Quantifying the Relative Thickness of Conductive Ferromagnetic Materials Using Detector Coil-Based Pulsed Eddy Current Sensors

Published on: January 16, 2020

Related Concept Videos

Eddy Currents

Eddy Currents

Since eddy currents occur only in conductors, magnets can separate metals from other materials. For example, in a recycling center, trash is dumped in batches down a ramp, beneath which lies a powerful magnet. Conductors in the trash are slowed by eddy currents, while nonmetals in the trash move on, separating from the metals. This works for all metals, not just ferromagnetic ones.
Other major applications of eddy currents appear in metal detectors and the braking systems of trains and roller...

Displacement Current

Displacement Current

Ampère's law, in its usual form, does not work in places where the current changes with time and is not steady. Thus, Maxwell suggested including an additional contribution, called the displacement current, Id, to the real conduction current I.

Significance of Displacement Current

Significance of Displacement Current

A displacement current is analogous to a real current in Ampère's law, participating in Ampère's law the same way as the usual conduction current. However, it is produced by a changing electric field. Displacement current is defined in terms of a time-varying electric field, and also has an associated displacement current density. By adding a term accounting for displacement current, Maxwell modified the existing Ampère's law, which is now called generalized Ampère's law.

Quantifying the Relative Thickness of Conductive Ferromagnetic Materials Using Detector Coil-Based Pulsed Eddy Current Sensors

Quantifying the Relative Thickness of Conductive Ferromagnetic Materials Using Detector Coil-Based Pulsed Eddy Current Sensors

Here, we present a protocol to quantify the relative thickness (i.e., thickness as a percentage with respect to a reference) of conductive ferromagnetic materials using detector coil-based pulsed eddy current sensors, while overcoming the calibration...

Magnetic Force Between Two Parallel Currents

Magnetic Force Between Two Parallel Currents

Two long, straight, and parallel current-carrying conductors exert a force of equal magnitude on one another. The direction of the force depends on the current direction in the conductors.
The force exerted by the magnetic field due to the first conductor over a finite length of the second conductor is given as the product of the current in the second conductor and the vector product of the length vector along the current element and the field due to the first conductor. According to the...

Magnetic Field Of A Current Loop

Magnetic Field Of A Current Loop

Consider a circular loop with a radius a, that carries a current I. The magnetic field due to the current at an arbitrary point P along the axis of the loop can be calculated using the Biot-Savart law.

Articles linked to this work by shared authors, journal, and citation graph.

NaF induced excessive autophagy of rat hippocampal neurons and NG108-15 cells via epigenetic upregulation of miR-183-5p.

Ecotoxicology and environmental safety·2026

Laparoscopic transfer of in vitro fertilized gene-edited embryos in pigs.

Theriogenology·2026

Advances in Long-Acting Ocular Therapies for Dry Eye Disease: Delivery Systems, Formulations, and Clinical Perspectives.

Experimental eye research·2026

Single-cell transcriptomic analysis reveals endothelial mitochondrial dysfunction and synaptic impairment underlying arsenic-induced hippocampal neurotoxicity in mice.

Ecotoxicology and environmental safety·2026

Reduced nerve growth factor (NGF) mediates arsenic-induced mitochondrial dynamics imbalance and neuronal damage both in vivo and in vitro.

Journal of Zhejiang University. Science. B·2026

Efficacy and safety of diazepam nasal spray in Japanese Pediatric patients with or at risk for status epilepticus: a phase 3, Multicenter, open-label clinical trial.

Epilepsy & behavior reports·2026

See all related articles