Stator Winding Axial Length Reduction via Coil Rotation

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Solution Overview

Problem

Existing methods for producing stator windings in electrical machines result in axial overhangs that are not optimally shortened, leading to inefficiencies in space utilization and cooling, and require complex handling and sorting of coil sides during production.

Innovation Solution

A method for producing a stator winding with a continuous wire that allows for a short axial length by rotating coils 90° relative to each other, enabling independent embossing of coil sides and flexible slot fill factors, which improves cooling and space utilization, and simplifies the production process by allowing for easier insertion and alignment of phase windings.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If conventional stator winding production methods are used, then the stator winding can be produced, but the axial overhang of coil side connectors is not optimally shortened, leading to increased axial length

Engineering Contradiction:
Improveaxial length of stator windingVSAvoidcomplexity of handling and sorting coil sides
Core Design Contradiction:
Length of moving objectVSEase of manufacture

Solution Approach 1:

The stator winding is segmented into multiple phase windings, each consisting of discrete coils that can be independently produced and then assembled. This segmentation allows for simplified handling during manufacturing while achieving the desired compact axial length through systematic arrangement of the segmented components.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent employs a multi-layer arrangement of coils in the axial dimension, with coils positioned at different axial levels and connected through coil side connectors. This dimensional approach allows the winding to achieve compact axial length while maintaining ease of manufacture through modular assembly of coils from different layers.

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

2Ease of manufacture

If coil sides are embossed together as a group, then the embossing process is simpler, but the coil sides near the yoke and on the slot side cannot be embossed independently

Engineering Contradiction:
Improveembossing process simplicityVSAvoidindependent embossing capability of coil sides
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The embossing process is segmented into separate operations for different coil side groups. Coil sides near the yoke can be embossed independently from those on the slot side, allowing each group to be optimized for its specific function while maintaining overall manufacturing efficiency.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Certain coil sides are embossed in advance during coil production, while other embossing operations are performed later during assembly. This preliminary action allows yoke-side coil sides to be prepared beforehand, enabling independent treatment and optimization of different coil side regions.

Inventive Principle:
Principle #10Preliminary action

3Length of moving object

If the axial length of the stator winding is reduced, then space utilization improves, but the groove cross section becomes more constrained

Engineering Contradiction:
Improveaxial length of stator windingVSAvoidfreedom in groove cross section design
Core Design Contradiction:
Length of moving objectVSAdaptability or versatility

Solution Approach 1:

The patent compensates for reduced axial length by utilizing the radial and circumferential dimensions more effectively. Multiple coils are arranged in different radial layers and angular positions, allowing the groove cross section to be optimized for electrical performance while maintaining compact axial length through three-dimensional space utilization.

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

Solution Approach 2:

Coils are nested in multiple radial layers within the stator winding structure, with inner-layer coils positioned radially inside outer-layer coils. This nesting arrangement allows the winding to achieve compact axial length while providing flexibility in groove cross section design through the layered configuration.

Inventive Principle:
Principle #7Nested doll (Nesting)

Data Source

PatentEP2436102B1Method for producing a stator winding of an electric machine, in particular for producing an alternator
Publication Date: 2019.12.11 SEG AUTOMOTIVE GERMANY GMBH
  • EP2436102B1 patent drawingFigure 1
  • EP2436102B1 patent drawingFigure 2~3
  • EP2436102B1 patent drawingFigure 4a~4b

AI summary

The invention relates to a method for producing a stator winding (18) of an electric machine (10), in particular of an alternator, the stator winding (18) comprising at least n phase windings (120, 121, 122, 123, 124) and a phase winding (120, 121, 122, 123, 124) having several directly consecutively wound coils (82) having coil sides (88) and coil side connectors (91), the coils (82) being divided into first coils (82.1) and second coils (82.2), by means of a forming tool (100), in which grooves (105, 106; 105', 106') suitable for accommodating the coils (82) are provided, a first coil (82.1) being arranged in one groove (105; 105') and a second coil (82.2) being arranged in another groove (105; 105'), characterized in that n-1 grooves (105, 106; 105', 106') are arranged between the first coil (82.1) and the second coil (82.2).