Shingled Planar Coil Layout for Cooling Dense Multilayer Windings

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing multilayer coil systems face challenges in achieving high energy density and efficient lateral heat dissipation due to limited thermal conductivity, primarily because of the large insulation distances required for electrical insulation, which hinder effective heat transfer across layers.

Innovation Solution

A coil system with a shingled arrangement of planar coils, where adjacent coils are laterally offset, combined with a passive conductor track structure that is galvanically isolated and thermally connected, allows for improved lateral heat transfer and efficient cooling through a cooling channel.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If large insulation distances are used for electrical insulation between planar coils, then electrical insulation reliability is improved, but thermal conductivity and heat dissipation efficiency deteriorate

Engineering Contradiction:
Improveelectrical insulation reliabilityVSAvoidheat dissipation efficiency
Core Design Contradiction:
ReliabilityVSTemperature

Solution Approach 1:

The patent transitions from lateral heat transfer within single layers to vertical heat transfer across layers by stacking planar coils with lateral offsets. This dimensional change allows heat to escape through the vertical axis, bypassing the lateral insulation barriers that prevent efficient heat dissipation.

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

Solution Approach 2:

The patent creates a nested structure where planar coils are stacked vertically with lateral offsets, forming a configuration where each coil partially overlaps with adjacent coils. This nesting enables thermal pathways to penetrate through multiple layers while maintaining electrical insulation through the lateral offset design.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Quantity of substance

If planar coils are stacked vertically to increase energy density, then compactness and energy density are improved, but lateral heat transfer capability deteriorates

Engineering Contradiction:
Improveenergy densityVSAvoidlateral heat transfer
Core Design Contradiction:
Quantity of substanceVSTemperature

Solution Approach 1:

The patent introduces vertical stacking with lateral offsets to create three-dimensional thermal pathways. This allows heat to transfer not only laterally within each layer but also vertically across layers, effectively bypassing the heat transfer limitations imposed by dense lateral packing.

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

Solution Approach 2:

The patent segments the thermal conduction path into multiple vertical channels created by the lateral offsets between stacked coils. Each offset creates a thermal pathway through the insulation layer, dividing the heat dissipation task into parallel vertical channels that collectively improve overall heat transfer efficiency.

Inventive Principle:
Principle #1Segmentation

3Temperature

If lateral offset arrangement is used to enable vertical heat transfer, then thermal conductivity is improved, but electrical insulation complexity increases

Engineering Contradiction:
Improvethermal conductivityVSAvoidelectrical insulation complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The lateral offset design serves dual functions: it creates vertical thermal pathways for heat dissipation while simultaneously maintaining electrical insulation between adjacent coils. This multi-functionality eliminates the need for additional complex insulation structures, as the offset arrangement itself provides both thermal and electrical functionality.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The structural arrangement of laterally offset stacked coils self-generates the necessary thermal pathways without requiring additional thermal management components. The same offset configuration that enables vertical heat transfer also inherently provides electrical insulation, making the system self-sufficient for both thermal and electrical requirements.

Inventive Principle:
Principle #25Self-service

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 shingled arrangement enhances thermal conductivity across layers, enabling higher energy density and efficient cooling while maintaining electrical insulation, thus optimizing the performance of compact electric motors.

Implementation Method 1

the heat generated in one conductor section has the opportunity to reach the edge region laterally by transferring to a vertically adjacent conductor section of another planar coil

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

efficient cooling through a cooling channel

Methodology Applied
Scientific EffectConvection: Convection

Data Source

PatentEP3815221B1Actively cooled coil
Publication Date: 2025.10.15 SCHAEFFLER TECHNOLOGIES AG & CO KG
  • EP3815221B1 patent drawingFigure 1~3
  • EP3815221B1 patent drawingFigure 4~5
  • EP3815221B1 patent drawingFigure 6~9

AI summary

The invention relates to a coil system comprising a first coil with a large number of planar coils (1-6) which are layered one above the other. In order to increase the energy density in a coil system of this kind, provision is made • for in each case two planar coils (1-6) which are situated directly one above the other to be vertically layered one on the other with a lateral offset in such a way that, at least in sections, in each case one turn of a first planar coil (1) and two turns of a second planar coil (2) which is arranged directly above the first planar coil are arranged with a partial overlap, • for the coil system to comprise a passive conductor track structure (7) which is DC-isolated from all current-carrying planar coils (1-6) of the coil system and has a large number of conductor tracks (23) which are layered one on the other and form a first comb-like structure, • for the first comb-like structure, at at least one edge region of the first coil, to engage into a second comb-like structure which is produced by the lateral offset of the outer turns of the planar coils (1-6) which are situated one above the other, and • for the lateral insulation gap (15) of the outer turn of each planar coil (1-6) from the passive conductor track structure (7) to be dimensioned in such a way that it causes base insulation of the first coil in relation to the passive conductor track structure (7).