Segmented Asynchronous Rotor for Large Diameter Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing asynchronous rotating electrical machines face challenges in manufacturing and maintenance due to the difficulty in producing large ferromagnetic sheets and the need for on-site assembly, which increases costs and complexity.
Innovation Solution
The rotor is segmented circumferentially into multiple segments, allowing for manufacturing off-site and easy assembly on the torque transmission shaft, with flexible connections and form-fitting elements for secure attachment, enabling efficient transportation and maintenance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the rotor is made as a single integrated unit with large ferromagnetic sheets, then the magnetic ring has sufficient structural integrity, but the manufacturing complexity and cost increase significantly
Solution Approach 1:
The rotor is divided into multiple independent segments (typically 3-6 segments) along the axial direction, each segment containing a portion of the ferromagnetic sheets and squirrel cage bars. This segmentation allows each segment to be manufactured separately using standard-sized ferromagnetic sheets, avoiding the need for large sheets while maintaining overall structural integrity through precise assembly and connection mechanisms between segments.
2Reliability
If the rotor is assembled on-site directly on the torque transmission shaft, then the assembly is secure, but the time and cost of maintenance increase
Solution Approach 1:
The rotor segments are designed as modular units that can be manufactured off-site and transported to the installation location. During maintenance, only the faulty segment needs to be removed and replaced, rather than disassembling the entire rotor. This significantly reduces maintenance time and allows for pre-assembled tested segments to be quickly swapped in.
Solution Approach 2:
The connection between rotor segments and the torque transmission shaft is designed to be dynamically adjustable, allowing for easy assembly and disassembly during maintenance while ensuring secure mechanical and electrical connections during operation. This includes removable coupling mechanisms and flexible electrical connections that maintain reliability during normal operation but facilitate quick maintenance.
3Reliability
If the rotor segments are connected with rigid connections, then the electrical connection is stable, but the assembly flexibility and ease of maintenance decrease
Solution Approach 1:
Flexible electrical connection elements (such as flexible busbars or elastic conductors) are used to connect the squirrel cage bars between rotor segments. These flexible connections maintain stable electrical contact during rotation and operation while allowing for thermal expansion, mechanical deformation, and easy assembly/disassembly of segments during maintenance.
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 segmentation reduces manufacturing, transportation, and maintenance costs while allowing for efficient assembly and repair of the asynchronous electrical machine, facilitating the use of asynchronous rotors with larger diameters and varying electrical poles.
Implementation Method 1
a magnetic ring comprising a plurality of axially stacked ferromagnetic metal layers
Implementation Method 2
a squirrel cage having a plurality of conductive elements regularly distributed over the periphery of the magnetic ring, each having two opposite ends extending axially beyond the magnetic ring
Data Source
Figure 1~2
Figure 3~4
Figure 5~7
AI summary
Rotor for an asynchronous electrical machine comprising a magnetic ring (20) comprising a plurality of layers of ferromagnetic metal sheets stacked axially and a squirrel cage (22) having a plurality of conductive elements (24) regularly distributed over the periphery of the magnetic ring (20) and each having two opposite ends extending axially beyond the magnetic ring (20) and each connected to a short-circuit crown (26; 28), arranged axially on either side of the magnetic ring (20) and intended to connect the ends of the conductive elements (24) electrically. The rotor is segmented circumferentially into at least two rotor segments (20a).