Segmented Stator Structure for Outside Winding Insertion
Solution Overview
Problem
Current stator configurations for radial flux machines with distributed windings face geometrical and manufacturing constraints, limiting the insertion of windings from the outside, which results in inefficiencies, high costs, and reduced torque yield due to the need for compression and deformation of conductor bars during assembly.
Innovation Solution
A stator design featuring a toothed star-shaped element with bridges connecting teeth and a segmented yoke ring allows for the insertion of distributed windings from the outside, enabling efficient assembly, high torque yield, and reduced rotor losses by using grain-oriented steel sheets and segmented components for improved magnetic performance and cost-effective manufacturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the stator uses a conventional design with teeth connected to a solid yoke, then the structural strength is sufficient, but the insertion of distributed windings from the outside is geometrically constrained and requires compression of conductor bars
Solution Approach 1:
The stator is divided into two separate components: a toothed star-shaped element and a yoke ring. The toothed star-shaped element contains the grooves for winding insertion and can be independently manufactured and assembled. This segmentation allows distributed windings to be inserted from the outside without geometric constraints, as the grooves can be designed with optimal opening dimensions independent of the yoke structure.
2Productivity
If conductor bars are compressed and deformed during assembly to fit into grooves, then the windings can be inserted, but manufacturing precision and quality are reduced
Solution Approach 1:
The toothed star-shaped element is pre-formed with grooves that have optimized dimensions and geometries for winding insertion. The grooves are designed beforehand to accommodate the distributed windings without requiring compression or deformation of the conductor bars during assembly, thereby maintaining manufacturing precision while enabling efficient assembly.
3Ease of manufacture
If tooth tips are made small or omitted to allow radial insertion of windings, then winding insertion is easier, but torque yield and rotor loss reduction are compromised
Solution Approach 1:
By separating the toothed star-shaped element from the yoke ring, the design allows the grooves to be positioned and dimensioned optimally for winding insertion without compromising the structural integrity or electromagnetic performance of the tooth tips. The tooth tips can maintain their full size and optimal geometry for torque generation while the grooves are designed independently for easy winding access.
4Volume of moving object
If the stator bore diameter is reduced or the number of grooves increased, then machine size is reduced, but geometric constraints on winding insertion from outside increase
Solution Approach 1:
The segmented stator design with a separate toothed star-shaped element allows the grooves to be optimally positioned and dimensioned regardless of the stator bore size or number of grooves. Each groove can be designed with sufficient opening dimensions to accommodate the distributed windings, enabling winding insertion from the outside even in compact machines with small bore diameters and high groove counts.
Data Source
AI summary
The invention relates to a stator for an electrical radial flux machine having a distributed winding and an internal rotor design, comprising: a toothed star-shaped element having multiple teeth, wherein stator grooves are provided between the teeth in the circumferential direction and wherein the teeth are connected by means of one or more bridges in the region facing an air gap between the stator and the rotor, and a yoke ring, wherein the toothed star-shaped element is accommodated, at least in sections, within the yoke ring.