Electrical Steel Lamination Stacks for Long Stator Production

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for producing stators for magnetic levitation systems, such as those used in hyperloop systems, are limited by the length of electrical steel laminations, which are typically restricted to the width of cold-rolled coils, resulting in stators that are no longer than approximately 1100 mm.

Innovation Solution

A method that involves providing an electrical steel strip with cut-outs on one or both sides along its length, allowing for continuous and repetitive punching operations to produce long, narrow laminations. These laminations are then stacked and post-processed to create stators of extended length.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If electrical steel laminations are produced from cold-rolled coils, then the manufacturing process is simple and straightforward, but the length of the laminations is limited to approximately 1100 mm

Engineering Contradiction:
Improvelength of laminationVSAvoidmanufacturing complexity
Core Design Contradiction:
Length of moving objectVSEase of manufacture

Solution Approach 1:

The strip of electrical steel is divided into multiple sections along its length, with cut-outs formed at specific locations. The strip is then separated at these cut-outs to produce individual laminations of desired length, enabling precise length control while maintaining continuous production

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Cut-outs are formed in the strip of electrical steel before the strip is separated into individual laminations. This preliminary action defines the future separation points and ensures that laminations will have the correct length and shape after separation

Inventive Principle:
Principle #10Preliminary action

2Length of moving object

If the length of electrical steel laminations is extended beyond conventional limits, then stators of extended length can be produced, but the number of interfaces between individual stators increases

Engineering Contradiction:
Improvelength of statorVSAvoidnumber of interfaces
Core Design Contradiction:
Length of moving objectVSReliability

Solution Approach 1:

The strip is divided into sections with cut-outs that define lamination boundaries. By controlling the position and spacing of cut-outs, laminations can be produced with precise lengths that minimize the number of interfaces required in the final stator assembly

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The method enables continuous production of long laminations from a continuous strip of electrical steel, maintaining the integrity and continuity of the magnetic path while reducing the number of discrete components and interfaces required

Inventive Principle:
Principle #20Continuity of useful action

Data Source

PatentEP3747114B1Method for producing a stack of electrical steel laminations and stack produced thereby
Publication Date: 2025.04.23 TATA STEEL NEDERLAND TECH BV
  • EP3747114B1 patent drawingFigure 1A
  • EP3747114B1 patent drawingFigure 2
  • EP3747114B1 patent drawingFigure 3A~3C

AI summary

This invention relates to a method for producing stacks of electrical steel laminations, e.g. for the production of stators for magnetic levitation trains and stacks produced thereby.