Synchronous Reluctance Rotor Structure for Stronger Direct Start
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing direct-start synchronous reluctance motors suffer from low efficiency and starting performance due to design issues with squirrel cage slots and magnetic flux distribution, leading to reduced mechanical strength and reliability.
Innovation Solution
A rotor structure with q-axis squirrel cage slots filled with conductive and non-magnetic material, featuring snap-fit limits, symmetric arrangement, and inclined squirrel cage slots to enhance d-axis magnetic flux and reduce q-axis flux, using aluminum or aluminum alloy for increased mechanical strength and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a rotor structure with separate pole pieces and flux barriers is used to achieve direct-start capability, then the motor can operate in both CFCC and DCM modes, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
The patent merges the pole pieces and flux barriers into a single integrated rotor structure. The rotor includes a rotor body with pole pieces formed as integral parts, where flux barriers are embedded within the pole pieces. This integration eliminates the need for separate assembly of pole pieces and flux barriers, reducing device complexity while maintaining the ability to operate in both CFCC and DCM modes.
Solution Approach 2:
The rotor structure utilizes composite construction by embedding flux barrier materials within the magnetic pole piece material. The pole pieces are formed with recesses that receive flux barrier elements, creating a composite structure that combines the magnetic properties of the pole piece material with the non-magnetic or low-remanence properties of the flux barrier material, enabling dual-mode operation without excessive complexity.
2Ease of manufacture
If conventional rotor structures are used, then manufacturing is simpler, but the motor cannot achieve true direct-start capability and requires external assistance
Solution Approach 1:
The rotor structure is pre-configured with specifically designed pole pieces and embedded flux barriers during manufacturing. The pole pieces have predetermined geometries with recesses that receive flux barriers, and the entire structure is designed beforehand to provide the necessary magnetic pathways for direct-start operation. This preliminary design and integration ensure that the rotor inherently possesses direct-start capability without requiring external assistance or complex assembly procedures.
3Adaptability or versatility
If flux barriers are embedded in pole pieces, then magnetic flux pathways are optimized for dual-mode operation, but the manufacturing precision requirements increase
Solution Approach 1:
The rotor structure is segmented into distinct functional zones: pole pieces with formed recesses and embedded flux barriers. Each pole piece is divided into a body portion and recess portions, allowing the flux barriers to be positioned precisely within dedicated spaces. This segmentation approach enables optimized magnetic flux pathways while providing natural positioning features that reduce the overall precision requirements compared to attempting to machine complex three-dimensional features.
Solution Approach 2:
The flux barriers serve as intermediary elements that mediate between the magnetic pole pieces and the air gap. By embedding these flux barrier elements within the pole piece recesses, the structure creates controlled magnetic pathways that guide flux distribution. The flux barriers act as intermediaries that simplify the magnetic circuit design while maintaining precise flux control, as the barriers are positioned within pre-formed recesses rather than requiring precise positioning in open space.
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
Enhances motor efficiency and starting ability by increasing the difference between d-axis and q-axis magnetic fluxes, improving mechanical strength, and eliminating the need for rare earth magnets, thus reducing costs and demagnetization risks.
Implementation Method 1
a first set of magnetic pole pieces extending from a first end of the rotor body along a radial direction towards a second end of the rotor body
Implementation Method 2
Direct-start synchronous reluctance electric motor
Data Source
Figure 1
Figure 2~3
AI summary
Provided are a rotor structure for a direct-start synchronous reluctance motor, and a motor, and a compressor. The rotor structure for the direct-start synchronous reluctance motor comprises: a rotor iron core, wherein q-axis squirrel-cage slots are provided in the outer peripheral surface of the rotor iron core, and the q-axis squirrel-cage slots are located at the q-axis of the rotor iron core; an end portion of at least one of two slot walls, close to the outer peripheral surface of the rotor iron core, of each of the q-axis squirrel-cage slots is configured to extend towards the outer slot wall, such that a snap-fit limiting space is formed between the two slot walls; and an electrically conductive but not magnetically conductive material is filled in the snap-fit limiting space. By applying the technical solution of the present application, the difference between the magnetic flux of eh d-axis and that of the q-axis can be effectively increased; the problems of the low efficiency and low rotation speed of an asynchronous electric motor are solved; and the output power and efficiency of an electric motor with the rotor structure are improved.