Two-Tooth Radial Flux Motor Layout for Large Air Gaps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Radial flux motors with large air gaps face issues of magnetic stray fluxes, which are costly to mitigate with complex windings, and struggle to maintain a large media flow cross-section while ensuring efficient electrical operation.
Innovation Solution
The design features an annular stator with only two stator teeth and windings arranged around the circumferential surface, using soft-magnetic composite material and a rotor with permanent magnets, allowing for a simple winding configuration that minimizes stray fields and maximizes the air gap, enabling efficient media flow and compact construction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If the air gap is designed to be large to allow media flow, then the throughflow cross-section is improved, but magnetic stray fluxes increase
Solution Approach 1:
The stator is segmented into exactly two stator teeth instead of using a continuous stator structure with multiple slots. This segmentation creates only two stator slots, dramatically reducing the number of openings that cause eddying and stray fluxes while maintaining a large air gap for media flow
Solution Approach 2:
The invention extracts and eliminates the problematic distributed winding structure from known radial flux motors. Instead, it uses a simplified winding arrangement with only two stator slots, removing the source of complexity and stray flux generation while preserving motor functionality
2Object-generated harmful factors
If a complicated distributed winding is provided to reduce stray fluxes, then magnetic stray fluxes are reduced, but device complexity and manufacturing cost increase
Solution Approach 1:
The winding system is segmented into only two stator slots instead of using distributed windings across multiple slots. This drastic reduction in the number of winding locations simplifies the overall winding structure and eliminates the complexity of distributed winding arrangements
Solution Approach 2:
Instead of using complex distributed windings to achieve simple flux patterns, the invention inverts the approach by using a simple two-slot stator structure with concentrated windings, which naturally produces the desired magnetic field distribution without requiring complicated winding patterns
3Area of stationary object
If the number of stator slots is increased to improve media flow, then throughflow capability is improved, but eddying of the medium increases
Solution Approach 1:
The stator structure is designed with only two strategically positioned stator teeth, creating large open spaces between them. This local structural choice minimizes the number of surfaces and openings that could cause eddying, while the large air gap provides sufficient throughflow cross-section for media passage
Solution Approach 2:
By segmenting the stator into only two teeth rather than using multiple closely-spaced slots, the invention reduces the total surface area and number of openings that interact with the flowing medium, thereby minimizing eddying effects while maintaining adequate flow capacity
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
This configuration reduces magnetic stray flux, allows for a large throughflow cross-section, and maintains efficient electrical operation with low power consumption, achieving good startup behavior and torque performance even with single-phase current.
Implementation Method 1
A first stator slot and a second stator slot, which is arranged opposite with respect to the rotation axis, extend along the circumferential surface between the stator teeth. At least one first winding (or a plurality of first windings) is arranged in the first stator slot and at least one second winding (or a plurality of second windings) is arranged in the second stator slot, wherein each winding extends over the end sides and on the outside and on the inside in the radial direction around the annular circumferential surface
Implementation Method 2
The rotor can have one or more one permanent magnets and/or soft-magnetic elements. Permanent magnets can preferably be used to form a permanently excited synchronous or brushless DC motor, abbreviated to BDLC
Implementation Method 3
The stator of the electric motor has, in particular, a soft-magnetic material, for example what is known as 'Soft Magnetic Composite' (SMC), or a combination of electrical sheets and SMC
Data Source
AI summary
An electric motor having a rotor with an axis of rotation and an annular stator surrounding the rotor, the stator extending along an axial direction parallel to the axis of rotation and having a first end face and a second end face pointing in opposite axial directions. The stator has exactly two stator teeth extending from an annular circumferential surface that runs between the end faces of the stator, in a radially inward direction to the rotor and facing one another in relation to the axis of rotation, a first stator slot and a second stator slot, which faces the first slot in relation to the axis of rotation, extending along the circumferential surface, between the stator teeth.