Design And Related Research On Permanent Magnetic Levitation Device

This paper presents a textile machine rotor supported by permanent magnetic bearing, realizingfrictionless bearing of spindle rotor on the textile machine without any complex electronic controlsystem,the stator of rotating driver is ordinary stator of asynchronous motors, two kinds of rotors aredesigned,one is solid rotor and the other is interference fitted by squirrel-cage rotor and the shaft. Forthe convenience of analysis of radial permanent magnet mechanical properties, this paper calculatesthe bearing capacity of single and multiple pairs permanent magnet rings using the equivalentmagnetic charge method.Meanwhile,for analyzing the bearing and suspension properties of permanentmagnet bearings,a proper model is established using Finite Element Analysis(FEA) software ANSYS,the structure and superimposition method are also designed according to the results that permanentmagnet will lose its suspension when the axial displacement of inner and outer magnet ring is greaterthan0.3mm,furthermore,this displacement will also produce axial force on the rotor,experimentsshow that the above results are correct.So,axial electromagnetic bearing is designed to decrease theaxial force which is benefited to the speed increasing. Since NdFeB can not bear large tensile stress，it is necessary to analysis its stress at high speed using theoretical calculation and simulation analysis,results of the two methods are nearly equal,which is also applied to analysis the reliability of magnetrings assembly.This paper also analyses the permanent magnet bearing rotor modal and critical speedusing Riccati transfer matrix method,getting modals and critical speeds of a certain stiffness,thenmakes comparision with experiment by excitation method,verifying the correctness of mathematicalmodel of permanent magnet bearing.The rationality of the design is verified by suspension androtating experiments after machining and assemblling the device into a whole.