Integrated Magnetic Choke Layout for Higher Differential Inductance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing electromagnetic interference (EMI) filters face challenges in achieving sufficient leakage inductance for differential mode interference while maintaining compact size, effective electrical insulation, and cost-effectiveness, particularly when combining common and differential mode chokes.

Innovation Solution

An integrated magnetic component that combines common and differential mode inductances, utilizing a closed-loop common mode core with adjacent surfaces to concentrate leakage flux, eliminating air gaps for improved insulation and heat dissipation, and using thermally conducting materials for enhanced heat management.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the distance between coils and core is increased to increase leakage inductance, then differential mode inductance is improved, but the size of the choke increases

Engineering Contradiction:
Improvedifferential mode inductanceVSAvoidsize of the choke
Core Design Contradiction:
ReliabilityVSVolume of moving object

Solution Approach 1:

The patent introduces a differential mode core that extends in a dimension perpendicular to the plane of the common mode core, creating a three-dimensional structure. This allows the leakage flux to be concentrated along the length of the differential mode core without increasing the footprint area, effectively increasing differential mode inductance while maintaining compact size.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The differential mode core acts as an intermediary structure that captures and concentrates the leakage flux generated by the common mode choke. By positioning the differential mode core adjacent to the common mode core with its longitudinal axis perpendicular to the winding window, it efficiently utilizes the leakage flux to achieve high differential mode inductance without requiring increased coil-to-core distance.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If traditional separators are used to maintain insulation, then electrical insulation is improved, but heat dissipation is reduced

Engineering Contradiction:
Improveelectrical insulationVSAvoidheat dissipation
Core Design Contradiction:
ReliabilityVSTemperature

Solution Approach 1:

The differential mode core acts as a thermal intermediary that provides a thermally conductive path away from the coils. By using materials with appropriate thermal conductivity for the differential mode core, heat generated by the coils can be efficiently dissipated through the core structure without compromising electrical insulation, as the thermal and electrical pathways are decoupled.

Inventive Principle:
Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The integrated magnetic component achieves a differential mode inductance five to ten times higher than prior art, with reduced size and cost, improved power density, and efficient heat dissipation, suitable for both common and differential mode EMI attenuation.

Implementation Method 1

The common mode core (2) has at least one surface (6) being adjacent to each of the at least two windings (4). The at least one surface (6) concentrates substantial leakage flux caused by the arrangement consisting of the common mode core (2) and the at least two windings (4)

Methodology Applied
Scientific EffectMagnetic flux concentration: Magnetic Field

Implementation Method 2

The gap (14) is arranged between the differential mode core (5) and the common mode core (2)

Methodology Applied
Scientific EffectMagnetic saturation prevention: Magnetic Saturation

Implementation Method 3

using thermally conducting materials for enhanced heat management

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentEP3683811B1Integrated magnetic component
Publication Date: 2025.06.25 DELTA ELECTRONICS (THAILAND) PUBLIC CO LTD
  • EP3683811B1 patent drawingFigure 1~2
  • EP3683811B1 patent drawingFigure 3~4
  • EP3683811B1 patent drawingFigure 5~8

AI summary

An integrated magnetic component comprises a common mode inductance and a differential mode inductance. The common mode inductance is formed by a common mode core surrounding a winding window and at least two windings wound around the common mode core and through the winding window. The differential mode inductance is formed by the at least two windings and a differential mode core being spaced from the common mode core by a gap. The differential mode core comprises at least one surface being adjacent to each of the at least two windings. Further, a filter for attenuating electromagnetic interference comprises an integrated magnetic component according to the invention. Even further, the integrated magnetic component according to the invention is used for attenuating electromagnetic interference, preferably in a vehicle, a data center, or a telecommunication unit. A method for manufacturing an integrated magnetic component according to the invention comprises two steps. One step comprises providing a common mode inductance formed by a common mode core surrounding a winding window, and at least two windings wound around the core and through the winding window. Another step comprises providing a differential mode core and spacing it from the common mode core by a gap, such that at least one surface of the differential mode core is adjacent to each of the least two windings.