Synchronous Reluctance Rotor Notch Layout for Low Torque Ripple
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Direct starting synchronous reluctance motors face issues with low efficiency, high torque ripple, and vibration noise due to the complexity and cost of traditional rotor manufacturing methods, as well as poor starting capability and insufficient salient pole ratio in existing designs.
Innovation Solution
The design incorporates a rotor core with slit grooves and filling grooves forming magnetic barrier layers, where notches at the ends of the filling grooves reduce torque ripple and vibration noise, and the use of conductive magnetic-insulation materials and end rings forms a squirrel cage for improved efficiency and starting capability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If traditional rotor manufacturing methods are used with filling material reaching rotor periphery, then the rotor structure is complete, but machining is required after filling which leads to long manufacturing time, low efficiency and high manufacturing cost
Solution Approach 1:
The patent pre-forms the filling material into a rod shape with a notch before insertion, so that the notch is already present in the filling material itself. This eliminates the need for subsequent machining operations on the rotor periphery, resolving the contradiction between manufacturing simplicity and productivity.
2Ease of manufacture
If long arc-shaped flux barriers in outer rotor region are all filled with aluminum or aluminum alloy, then the rotor structure is simplified, but the starting capability of the machine becomes poor
Solution Approach 1:
The patent applies different filling strategies to different regions: the outer rotor region flux barriers are left unfilled or partially filled, while inner rotor region flux barriers are filled with conductive material. This local differentiation improves starting capability by maintaining flux paths in the outer region while providing squirrel cage action in the inner region.
3Ease of manufacture
If slot portions are arranged radially at equal intervals in circumferential direction, then the manufacturing is simplified, but the flux between slot portions flows radially perpendicular to rotor surface which blocks flux flow in q-axis direction, so salient pole ratio is not large and output and efficiency are insufficient
Solution Approach 1:
The patent positions the notches in the filling material asymmetrically relative to the rotor geometry, specifically aligning them with the d-axis direction. This asymmetric placement creates preferential flux paths that enhance the salient pole effect and improve the inductance difference between d-axis and q-axis, thereby increasing motor efficiency.
4Reliability
If the rotor is provided with slit portions and slot portions filled with conductivity materials, then the motor can start easily, but the slot portions block flux flow in q-axis direction which reduces salient pole ratio and output
Solution Approach 1:
The patent segments the filling material into multiple rods, each with its own notch, and places them at specific positions within the flux barriers. This segmentation allows selective placement of conductive material to provide starting capability while maintaining flux paths in other regions, thus preserving motor output.
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 torque ripple and vibration noise while enhancing the motor's efficiency and starting capability by optimizing the reluctance torque and inductance difference between the d-axis and q-axis, resulting in improved motor performance and reduced manufacturing costs.
Implementation Method 1
realizing a start by generating a torque through a squirrel cage induction
Implementation Method 2
carrying out a constant-speed running by generating a reluctance torque through a rotor inductance gap
Data Source
AI summary
The present disclosure provides a direct starting synchronous reluctance motor rotor, a motor and a rotor manufacturing method. The direct starting synchronous reluctance motor rotor comprises: a rotor core provided with a plurality of slit grooves, two ends of each of the slit grooves being provided with a filling groove respectively to form a magnetic barrier layer, a first end of the filling groove being disposed adjacent to the slit groove, a second end of the filling groove being extended towards an outside of the rotor core, and an outer peripheral surface of the rotor core being provided with a notch communicated with the second end of the filling groove. By disposing notches and bevels at the end of the filling grooves, a reluctance torque of the motor can be increased, and then torque ripples generated by rotor and stator slots can be weakened mutually, thereby achieving the purpose of reducing the torque ripple of the motor and vibration noise of the motor, while improving an efficiency of the motor with the rotor and a starting capability of the motor.