# Electromagnetic Analysis and Experimental Study of Laminated Mn-Zn Toroidal Ferrite Cores for High-Frequency Inductance and Impedance Enhancement

## TL;DR

This paper studies how laminated Mn-Zn toroidal ferrite cores can improve high-frequency inductance and reduce electromagnetic interference in power electronics.

## Contribution

The study introduces a validated analytical method for optimizing lamination structures to enhance impedance and frequency performance.

## Key findings

- A four-layer lamination increases resonant frequency by about 2.8 times compared to a monolithic core.
- Lamination effectively interrupts eddy current loops and mitigates the skin effect.
- The proposed method extends stable frequency bandwidth and prevents impedance degradation.

## Abstract

To achieve high-frequency inductance and impedance enhancement for effective electromagnetic interference (EMI) mitigation in power electronics, this paper presents an electromagnetic analysis and experimental study of laminated Mn-Zn toroidal ferrite cores. The electromagnetic field is analyzed using a 2D analytical solution based on a simplified Cartesian approximation. Although neglecting curvature, this approach enables efficient eigenfunction expansion and is rigorously validated against cylindrical finite difference (FDM) and 3D finite element (FEM) benchmarks. The results demonstrate that lamination effectively interrupts eddy current loops; notably, a four-layer structure increases the resonant frequency by approximately 2.8 times compared to a monolithic core. Experimental measurements confirm that this design significantly mitigates the skin effect and extends the stable frequency bandwidth. This study establishes a validated, computationally efficient methodology for optimizing core geometries to prevent impedance degradation.