Segmented Permanent Magnet Rotor for High-Speed Centrifugal Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-speed induction machines with surface permanent magnets face challenges due to increased centrifugal forces, which can lead to deformations and require stronger magnets, increasing weight and demands on holding means, while existing solutions for fixing magnets are complex and may not fully utilize magnetic flux potential.
Innovation Solution
A rotor design featuring permanent magnet elements with two active surfaces, connected via a support profile with a groove for form-fitting engagement with holding elements, allowing for stable and efficient fixation without undercuts or complex profiles, enabling the use of thin, lightweight magnets and optimizing magnetic flux.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If permanent magnet elements are made thicker to withstand high centrifugal forces in high-speed machines, then mechanical strength and stability are improved, but weight increases and magnetic flux requirements increase leading to heavier stator and rotor
Solution Approach 1:
The permanent magnet elements are divided into segmented structures with recesses in their outer surfaces. These recesses allow the magnets to be thinner while maintaining mechanical stability through the holding elements that engage with the recesses, thus reducing the overall weight of the rotor and stator without compromising strength.
Solution Approach 2:
Holding elements are inserted into the recesses of the permanent magnet elements, creating a nested structure where the holding elements are positioned within the magnet structure. This allows for efficient use of space and reduces the need for thicker magnets, thereby reducing weight while maintaining mechanical integrity under centrifugal forces.
2Weight of moving object
If permanent magnet elements are made thinner to reduce weight, then weight and material requirements are reduced, but mechanical strength decreases making them susceptible to deformation under centrifugal forces
Solution Approach 1:
The permanent magnet elements feature recesses in their outer surfaces that engage with holding elements. This segmented design allows the magnets to be thinner while the holding elements provide the necessary mechanical support to withstand centrifugal forces, thus reducing weight without sacrificing strength.
Solution Approach 2:
Holding elements act as intermediaries between the permanent magnet elements and the rotor structure. These holding elements engage with the recesses in the magnets and provide mechanical support, allowing the magnets to be thinner while still withstanding the high centrifugal forces in high-speed machines.
3Stability of the object's composition
If complex fixation methods such as dovetail grooves or bandages are used to secure permanent magnets, then mechanical stability is improved, but device complexity and manufacturing complexity increase
Solution Approach 1:
The fixation system is segmented into simple recesses in the permanent magnet elements and corresponding holding elements. This segmentation replaces complex dovetail grooves or bandages with simpler geometric features that are easier to manufacture while providing adequate mechanical stability through the engagement of the holding elements with the recesses.
Solution Approach 2:
Instead of creating complex external fixation structures like dovetail grooves or bandages, the design inverts the approach by incorporating recesses directly into the permanent magnet elements themselves. The holding elements then simply engage with these recesses, simplifying the overall fixation structure while maintaining stability.
4Quantity of substance
If surface magnets are used to maximize flux potential, then magnetic flux density is improved, but mechanical strength decreases making them more susceptible to deformation under centrifugal forces
Solution Approach 1:
The surface magnets are designed with recesses in their outer surfaces, creating a segmented structure. This allows the magnets to maintain thin profiles for maximizing flux potential while the recesses engage with holding elements that provide the necessary mechanical support to withstand centrifugal forces in high-speed machines.
Solution Approach 2:
Holding elements serve as intermediaries that connect the thin surface magnets to the rotor structure. These holding elements engage with the recesses in the magnets, providing mechanical support without interfering with the magnetic flux path, thus allowing the magnets to be thin for maximum flux while maintaining mechanical strength.
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 design enhances the stability and magnetic performance of surface magnets, allowing for high power density with reduced weight and complexity in the rotor and stator, while maintaining high flux densities and preventing magnetic short circuits.
Implementation Method 1
permanent magnet elements (5, 6) for a synchronous electric machine, wherein the permanent magnet elements (5, 6) each have two active surfaces (8, 9) through which a magnetic field passes perpendicularly
Implementation Method 2
the second active surface (9) is designed as a radial surface for an annular gap (air gap) between the rotor and a stator
Implementation Method 3
The support profile is provided with a groove (11) which is designed for a form fit acting in the radial direction with a holding element (17) arranged on the rotor
Implementation Method 4
High centrifugal forces occur in high-speed induction machines, which can lead to deformations or changes in position if the permanent magnet elements are too thin
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
The invention relates to a permanent magnet element (5, 6) for an electric synchronous machine, comprising two active surfaces (8, 9) that are vertically intersected by a magnetic field, the first (8) being designed to be installed on a circumferential surface (3) of a rotor (1) of an electric machine, and the second (9) being designed as a radial surface for an annular gap between the rotor (1) and a stator, a web surface which connects said first and second active surfaces (8, 9) being designed as a profiled carrier section (10) that is provided with a groove (11) and is designed to form-fittingly connect, in the radial direction, to a retainer element (17) that is arranged on said rotor (1). The invention also relates to a rotor (1) for an electric synchronous machine, said rotor comprising a plurality of magnetic poles (4) each having a plurality of permanent magnet elements (5, 6) according to one of claims 1 to 5, and said rotor (1) having retainer elements (17) arranged thereupon whose outer contours engage form-fittingly into the profiled carrier sections (11) of adjacent permanent magnet elements (5; 5, 6) of a magnetic pole (4).