Flat Wire Stator Insulating Layer Thickness Variation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing stator coil designs using flat wires face a trade-off between in-slot space factor and insulation performance, where thick insulating layers for interphase insulation impede the improvement of the in-slot space factor, leading to limitations in motor size reduction and output characteristics.
Innovation Solution
A stator design featuring flat wires with varying insulating layer thicknesses, where the layer is thicker only at adjacent portions to ensure interphase insulation and thinner elsewhere, allowing for improved in-slot space factor while maintaining effective insulation performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a thick insulating layer is applied to the entire flat wire to ensure interphase insulation at coil end portions, then insulation performance is improved, but the in-slot space factor of the stator coil deteriorates
Solution Approach 1:
The insulating layer is designed with different thicknesses at different locations: a first insulating layer with greater thickness is applied to the first surface of the flat wire that contacts adjacent flat wires in the radial direction within the same slot, while a second insulating layer with smaller thickness is applied to other surfaces. This local differentiation ensures adequate insulation where needed (within-slot insulation) while reducing overall insulation material usage, thereby improving the in-slot space factor without compromising insulation performance.
2Quantity of substance
If a thin insulating layer is used to improve in-slot space factor, then the in-slot space factor is improved, but insulation performance deteriorates
Solution Approach 1:
The insulating layer is designed with different thicknesses at different locations: a first insulating layer with greater thickness is applied to the first surface of the flat wire that contacts adjacent flat wires in the radial direction within the same slot, while a second insulating layer with smaller thickness is applied to other surfaces. This local differentiation ensures adequate insulation where needed (within-slot insulation) while reducing overall insulation material usage, thereby improving the in-slot space factor without compromising insulation performance.
3Reliability
If a coil insulating member is attached to ensure interphase insulation, then insulation performance is improved, but device complexity and manufacturing difficulty increase
Solution Approach 1:
The insulating layer is integrated directly into the flat wire structure during the wire manufacturing process, forming an insulating flat wire where the insulating layers are pre-applied to the conductor. This merging of the insulating function into the wire itself eliminates the need for separate coil insulating members, thereby reducing device complexity and simplifying the manufacturing process while ensuring adequate insulation performance.
Solution Approach 2:
The insulating layers are applied to the flat wire in advance during wire manufacturing, creating a pre-insulated conductor before the coil winding process. This preliminary insulation application ensures that insulation requirements are met before assembly, eliminating the need for additional insulation components and simplifying subsequent manufacturing steps.
Data Source
AI summary
A flat wire (36) that forms a stator coil (16) has an insertion portion (22) that is inserted into a slot (14), and a coil end portion (30) that protrudes from an end portion of the stator coil (16). An insulating layer of an adjacent portion (38) that is adjacent to a flat wire (36) of a different phase at the coil end portion (30) is thicker than an insulating layer in another region. Setting the thickness of the insulating layer of each part according to the required insulation performance in this way makes it possible to make the overall insulating layer thinner, and improve the in-slot space factor of the stator coil while ensuring insulation performance.