Insulating Former for Axial Flux Stator Winding
Solution Overview
Problem
The existing insulation arrangements for axial flux machines are complex, difficult to assemble, and inefficient, requiring excessive material and process steps to maintain minimum clearance distances between copper windings and steel stators, leading to increased costs and reduced motor efficiency.
Innovation Solution
The use of insulating formers that closely conform to the shape of stator teeth, reducing the mean length of winding coils and eliminating the need for additional clearance, with features like flanges, flexible clips, and wiring channels to simplify assembly and improve electrical isolation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional insulating material with cuffed ends is used to maintain minimum clearance distance, then electrical isolation is achieved, but winding length increases and material usage increases
Solution Approach 1:
An insulating former is introduced as an intermediary component between the stator tooth and the winding coil. This former serves as a mediator that provides the necessary electrical isolation and maintains clearance distance, allowing the winding to be optimized for minimal length while still meeting insulation requirements.
Solution Approach 2:
The insulation function is segmented from the winding structure. Instead of using cuffed insulating material that extends the winding length, the insulation is provided by a separate insulating former that fits within the slot, decoupling the insulation requirement from the winding dimensional constraints.
2Reliability
If conventional insulating material with cuffed ends is used to maintain minimum clearance distance, then electrical isolation is achieved, but assembly complexity increases
Solution Approach 1:
The assembly process is segmented into distinct steps: first inserting the insulating former into the slot, then placing the winding coil. This segmentation allows each component to be positioned independently without requiring complex coordination of multiple components simultaneously, simplifying the overall assembly process.
Solution Approach 2:
The insulating former is prepared and positioned in the slot before the winding coil is installed. This preliminary action establishes the insulation barrier in advance, simplifying the subsequent winding installation process and eliminating the need for complex coordination of cuff positioning and clearance verification during assembly.
3Reliability
If conventional insulating material with cuffed ends is used, then minimum clearance distance is maintained, but motor efficiency decreases
Solution Approach 1:
The insulating former acts as a mediator that enables the use of shorter, more efficient windings while still maintaining the required electrical isolation and clearance distances. This allows the motor to operate with optimized winding lengths that reduce resistance and improve efficiency.
Solution Approach 2:
The invention changes the parameter of winding length by enabling shorter windings through the use of insulating formers. This parameter change directly improves motor efficiency by reducing the mean length of turn and associated copper losses, while the insulating former maintains the necessary electrical isolation parameters.
Data Source
AI summary
A stator 20 for an axial flux machine such as a motor or generator. The stator includes a stator core 32 having a back plane 24 which in use is disposed perpendicularly about a rotational axis of the machine. A plurality of teeth 26 extend axially from the back plane so as to form winding receiving slots 28 between adjacent teeth. The stator also includes an electrical winding 30 including a plurality of coils 32, each coil being located about a tooth of the stator core and being electrically isolated from the stator tooth by means of an insulating former 34 having a shape which closely conforms to the shape of the stator tooth. The coils 32 are interconnected to form the winding 30. A method of constructing a stator is also disclosed.