Analysis of double side ironless permanent magnet linear synchronous machine with low normal force
Xinghua He1, Qixin Sun1, Liang Yan2,3,4
1School of Automation Science and Electrical Engineering, Beihang University, Beijing, 100191, China.
Scientific Reports
|April 29, 2025
Summary
This study investigates the normal force in double-sided permanent magnet linear synchronous machines (DPMLSMs), often overlooked but critical for system performance. Findings show installation offset significantly impacts normal force, while more segments reduce it.
Area of Science:
- Electromagnetism
- Mechanical Engineering
- Energy Conversion Systems
Background:
- Electromagnetic linear machines convert electrical energy to linear motion.
- Conventional studies prioritize axial thrust, neglecting normal force in DPMLSMs.
- Unbalanced normal force causes detrimental effects like increased friction, vibration, and noise.
Purpose of the Study:
- To systematically analyze the normal force in DPMLSMs.
- To provide theoretical design support for mitigating unwanted normal forces.
- To understand the impact of mover deformation and Halbach segment configuration.
Main Methods:
- Analytical formulation of magnetic field distribution.
- Analysis of normal force under varying mover deformation and Halbach segment counts.
- Optimization of pole width.
- Experimental verification of analytical and numerical models.
Main Results:
- Mover deformation and installation offset significantly influence normal force.
- Increasing the number of Halbach segments reduces the normal force.
- Optimized pole width contributes to improved performance.
Conclusions:
- Normal force is a critical parameter in DPMLSM design, not just axial thrust.
- Understanding and controlling normal force is essential for reducing friction, vibration, and noise.
- The study provides a validated framework for designing DPMLSMs with minimized normal forces.
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