Stator Lamination Axial Tunnels for NVH Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric vehicles experience high levels of Noise, Vibration, Harshness (NVH) due to the electric motor, which affects user experience and is a significant issue in the automotive industry, with existing solutions failing to adequately address vibration and noise reduction.
Innovation Solution
The electric-machine stator lamination features axial tunnels filled with a damping medium, weight-reduction holes, and mounting holes, which increase the damping coefficient of the stator iron core, reducing vibration and noise transmission by weakening the paths of vibration and noise, and improving passenger comfort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the stator iron core is made solid and dense, then the structural strength is improved, but the vibration and noise transmission is enhanced
Solution Approach 1:
The patent introduces a porous structure into the stator iron core by creating axial tunnels filled with damping medium. This porous configuration allows the damping medium to absorb and dissipate vibration energy while maintaining the overall structural integrity of the stator iron core, thereby reducing vibration and noise transmission without significantly compromising structural strength.
Solution Approach 2:
The patent combines the stator iron core material with a damping medium filled in axial tunnels to create a composite structure. This composite configuration leverages the strength of the iron core while utilizing the vibration-damping properties of the damping medium, achieving both structural strength and vibration reduction simultaneously.
2Object-generated harmful factors
If damping structures are added to the stator, then the vibration and noise reduction is improved, but the device complexity is increased
Solution Approach 1:
The patent divides the stator iron core into segments by introducing axial tunnels that run through the yoke. These tunnels are filled with damping medium to create localized damping zones. This segmentation approach allows vibration damping to be implemented in specific areas without requiring complete structural redesign, thereby controlling device complexity while achieving vibration reduction.
Solution Approach 2:
The patent applies damping medium locally within axial tunnels positioned at the stator yoke where vibration transmission occurs. This localized application of damping material targets specific vibration paths without adding damping structures throughout the entire stator, thus reducing vibration and noise while minimizing the increase in device complexity.
3Reliability
If axial tunnels are introduced in the stator yoke, then the damping coefficient is increased, but the structural strength is reduced
Solution Approach 1:
The axial tunnels create a porous structure within the stator yoke that is filled with damping medium. This porous configuration increases the damping coefficient by providing pathways for vibration energy dissipation while maintaining sufficient structural strength through the surrounding iron core material.
Solution Approach 2:
The combination of the solid stator iron core with the damping medium-filled tunnels creates a composite structure where the iron core provides structural strength and the damping medium provides vibration damping. This composite approach balances structural strength and damping coefficient effectively.
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
The solution effectively reduces NVH levels by mitigating vibration and noise, achieving significant noise reduction of 3-5dBA at 48-order radial and axial frequencies and 4-13dBA at 96-order radial and axial frequencies, enhancing passenger comfort and overall machine performance.
Implementation Method 1
axial tunnels which are filled with a damping medium
Implementation Method 2
The damping medium is selected from a group consisting of: a rubber-based material, a bitumen-based material, an asphalt-based material, a polymer-based material, a viscoelastic material, and a magnetorheological material
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The present disclosure discloses an electric-machine stator lamination (1), an electric-machine stator iron core and an electric machine, which effectively solves the technical problem in the prior art that electric machines have high NVHs. The yoke of the electric-machine stator lamination (1) is circumferentially provided with a plurality of axial tunnels (6), and the tunnels (6) are empty or are filled with a damping medium. The electric-machine stator iron core is formed by laminating a plurality of the electric-machine stator laminations (1) or is integrally manufactured. The electric machine includes an electric-machine housing (4) and the electric-machine stator iron core, the outer circumference of the electric-machine stator iron core and an inner wall of the electric-machine housing (4) have gaps (5) therebetween, and the gaps (5) are empty or are filled with a damping medium. The structures in which the gaps (5)/tunnels (6) are empty or the gaps (5)/tunnels (6) are filled with a damping medium can weaken the vibration energy generated by the stator to the electric-machine housing (4), increasing the damping coefficient of the electric-machine housing (4), reduces the response amplitude/frequency of the electric-machine housing (4), weaken the paths of the vibration/noise transmission , and reduce the response amplitudes, thereby inhibiting vibration and noise, to effectively reduce the overall NVH level.