Vibration Analysis of PMLSM Considering Magnetostriction Under High-Intensity Magnetic Fields

The generation of high-intensity magnetic fields is often necessary in permanent magnet linear synchronous motor (PMLSM) systems to meet the requirements of fast response and high thrust density. However, there is currently a lack of research on the magnetic field harmonics and vibration issues that arise in PMLSM under such operating conditions. This article investigates the influence of iron core saturation on air-gap magnetic field harmonics under high-intensity magnetic fields. The impact of saturation on normal electromagnetic force harmonics is obtained by analyzing temporal and spatial harmonics of air-gap flux density and conducting analytical calculations for electromagnetic force. In addition, this article analyzes the frequency characteristics of vibrations caused by magnetostriction combined with tooth magnetic density harmonics. The theoretical results are validated through finite-element simulation and vibration experiments. A new method to reduce the vibrations of PMLSM is proposed.