Coil Disc Winding Layout for High Copper Fill in Electric Machines
Solution Overview
Problem
Existing electric machine coil designs face inefficiencies due to the use of flat wire in meander configurations, which lead to electromagnetic inefficiencies and difficulties in achieving a compact, multiphase structure.
Innovation Solution
A coil module with a coil disc made of an insulating material and circumferentially arranged windings, featuring active and passive regions with varying thicknesses and cross-sectional shapes, allowing for increased copper filling ratio and efficient use of space, enabling a compact and efficient three-phase operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If flat wire is used in a meander configuration to achieve high density of electrically conductive material, then copper filling ratio is improved, but electromagnetic efficiency deteriorates and multiphase structure becomes difficult
Solution Approach 1:
The coil structure is segmented into multiple coil discs, each containing individual windings arranged circumferentially. This segmentation allows for optimized current paths in each winding while maintaining high copper density, resolving the conflict between copper filling ratio and electromagnetic efficiency by enabling proper phase arrangements for multiphase motors
Solution Approach 2:
The invention transitions from a planar meander configuration to a three-dimensional structure with coil discs stacked axially. Each coil disc contains windings with active regions extending radially and passive regions extending tangentially, creating a spatial arrangement that improves electromagnetic efficiency while maintaining high copper density through vertical stacking
2Quantity of substance
If passive regions are made thicker to accommodate more copper material, then copper filling ratio is improved, but axial thickness of coil disc increases
Solution Approach 1:
Multiple coil discs are nested axially, with each disc containing windings that have passive regions overlapping adjacent windings. This nesting allows copper material to be efficiently packed in the radial and tangential directions without requiring increased axial thickness, as the overlapping passive regions utilize space within the same axial envelope
Solution Approach 2:
The windings have non-uniform cross-sections with different thicknesses in active regions versus passive regions. The passive regions are made thicker locally to accommodate more copper material and improve copper filling ratio, while the active regions maintain optimal thickness for electromagnetic performance, resolving the contradiction through localized material distribution
3Ease of manufacture
If uniform thickness is used for all regions of windings, then manufacturing is simplified, but space utilization deteriorates and compact structure is reduced
Solution Approach 1:
The winding cross-sectional parameters are varied between active and passive regions, with passive regions having greater thickness to accommodate more copper material. This parameter change optimizes space utilization and copper packing density while the overall winding geometry remains regular enough for practical manufacturing through conventional winding processes
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 design achieves a compact structure with enhanced efficiency and power density by optimizing the arrangement of windings and magnetic field interaction, allowing for improved performance and reduced space requirements.
Implementation Method 1
a high density of electrically conductive material is ensured in the area of a magnetic field generated by permanent magnets
Data Source
AI summary
The present invention relates to a coil module for an electric machine, comprising at least one coil disc comprising a coil carrier made of an electrically insulating material and a plurality of individual windings made of an electrically conductive material and being circumferentially arranged on the coil disc around a center of the coil disc. Each of the windings comprises two active regions extending radially from the center and two passive regions extending tangentially at its radially outer and inner edges, wherein, in a top view of the coil disc, the active regions of different windings do not overlap each other, but each passive region of one of the windings partially overlaps the corresponding passive regions of the two directly adjacent windings. In the active regions, the respective winding in cross-section has a greater thickness in the axial direction than in the passive regions.