Electromagnetic Actuator Pole Face Segmentation for Lower Eddy Loss

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Transportation systems face challenges in achieving high speed, high efficiency, and high power density due to track losses caused by eddy currents induced in electromagnetic actuators, which affect magnetic flux distribution and increase power consumption.

Innovation Solution

The electromagnetic actuator incorporates magnetic-flux changing components at the pole faces to spread magnetic flux over a wider area, reducing magnetic flux density in the active airgap and minimizing eddy currents, while retaining electrical windings using cold plates and retaining devices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Force

If electromagnetic actuator operates at high speed with concentrated magnetic flux, then magnetic force is improved, but eddy current losses increase

Engineering Contradiction:

Improvemagnetic forceVSAvoideddy current losses

Core Design Contradiction:

ForceVSLoss of energy

Solution Approach 1:

The pole face is segmented into multiple independent magnetic flux concentrating components arranged in parallel. Each component concentrates flux locally while the segmentation prevents eddy currents from forming large circulating loops across the entire pole face, thereby reducing eddy current losses while maintaining total magnetic force

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the pole face are equipped with dedicated flux concentrating components that locally concentrate magnetic flux where needed. This local concentration approach maintains magnetic force in critical areas while limiting the area over which eddy currents can develop, reducing overall energy losses

Inventive Principle:

Principle #3Local quality

2Force

If magnetic flux density is increased in active airgap, then magnetic force is improved, but power consumption increases

Engineering Contradiction:

Improvemagnetic forceVSAvoidpower consumption

Core Design Contradiction:

ForceVSUse of energy by moving object

Solution Approach 1:

The magnetic flux concentration is achieved through multiple segmented components rather than a single high-density source. This segmentation allows the system to achieve the required total magnetic force through distributed lower-density flux concentration, reducing the overall power consumption while maintaining force output

Inventive Principle:

Principle #1Segmentation

3Loss of energy

If magnetic flux is spread over wider area, then eddy currents are reduced, but magnetic force decreases

Engineering Contradiction:

Improveeddy current lossesVSAvoidmagnetic force

Core Design Contradiction:

Loss of energyVSForce

Solution Approach 1:

The pole face is divided into multiple flux concentrating components that collectively cover a wide area. Each segment concentrates flux locally to maintain force while the distributed arrangement across the wide area prevents large-scale eddy currents, achieving both goals simultaneously

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Instead of spreading flux uniformly in a single dimension which would reduce density, the invention uses multiple discrete components arranged in a multi-dimensional pattern across the pole face. This approach maintains effective flux concentration in the active airgap while distributing the magnetic field coverage to reduce eddy currents

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

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

This design reduces power consumption and maintains magnetic force by minimizing eddy currents, ensuring efficient operation of the actuator at high speeds.

Implementation Method 1

one or more magnetic-flux changing components at the pole portions, a respective magnetic-flux changing component located at a respective pole face, the respective magnetic-flux changing component configured to change magnetic flux density at a respective track-facing surface relative to the respective pole face

Methodology Applied

Scientific EffectMagnetic flux: Magnetic Field

Implementation Method 2

Track losses caused by such an electromagnetic actuator may be problematic... minimizing eddy currents

Methodology Applied

Scientific EffectEddy currents: Eddy Currents

Implementation Method 3

electrical windings around the pole portions

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 4

Force-producing electromagnetic actuator... electromagnetic actuator for generating force

Methodology Applied

Scientific EffectElectromagnetic force: Lorentz Force

Data Source

PatentUS12512742B2Force-producing electromagnetic actuator

Publication Date: 2025.12.30 DP WORLD LOGISTICS US HOLDINGS INC

AI summary

An electromagnetic actuator for generating force is provided. The electromagnetic actuator includes a ferromagnetic body extending along a longitudinal axis, the ferromagnetic body comprising: a back-iron portion; and a pair of pole portions, extending from the back-iron portion, the back-iron portion connecting the pair of pole portions. The electromagnetic actuator further includes one or more magnetic-flux changing components at the pole portions, a respective magnetic-flux changing component located at a respective pole face, the respective magnetic-flux changing component configured to change magnetic flux density at a respective track-facing surface relative to the respective pole face. The electromagnetic actuator further includes electrical windings around the pole portions.