Parameter Optimization Of Halbach Permanent Magnet Array For Magnetic Levitation Planar Motor Based On Magnetic Field Harmonic Analysis

With the development of the precision machining industry,higher requirements have been put forward for precision positioning stages.The magnetic levitation planar motor is a new type of drive element,but there is very little research on it in China.The Halbach permanent magnet array is the core part of the magnetically levitated planar motor,and its special magnetic field characteristics make the application in aviation,aerospace,defense,equipment manufacturing,industrial and agricultural production and daily life.The main research of this paper on Halbach permanent magnet array for moving coil magnetic levitation planar motor is as follows:First of all,this paper synthesizes the Halbach permanent magnet array developed at home and abroad,takes the Halbach permanent magnet array as the object,uses the theoretical method to deduce,establishes the magnetic field mathematical model of Halbach permanent magnet array of magnetic levitation plane motor,gives the comparison between the simulation and the real measurement.Secondly,in terms of finite element modeling,multi-physical field simulation software COMSOL is used to model according to Halbach permanent magnet array model.Firstly,two-dimensional Halbach permanent magnet array is modeled,the established model material properties are assigned,and then the grid is divided,and finally the general steps of operation processing are carried out.On the basis of two-dimensional Halbach permanent magnet array,permanent magnet steel thickness was added to obtain three-dimensional Halbach permanent magnet array modeling.The two-dimensional Halbach permanent magnet matrix and three-dimensional Halbach permanent magnet array were established respectively.The magnetic field intensity of Halbach permanent magnet array magnetic steel with different widths and thicknesses of large and small permanent magnets was studied by finite element analysis.Determine the size of each part of Halbach permanent magnet array,including the thickness and width of magnetic steel,etc.Finally,the finite element model of Halbach permanent magnet array is used to analyze the X-component and Z-component distribution of magnetic flux density of Halbach permanent magnet array in time domain and frequency domain.The total harmonic distortion rate of magnetic field THD value is introduced to measure the size of flux density distribution of permanent magnet array under different structures.According to the THD value,the width and thickness of large and small permanent magnet steel of Halbach permanent magnet array are selected to maximize the flux density distribution and maximize the utilization of magnetic field energy.The magnetic field contains different odd harmonics,and the amplitude of these harmonics will decrease with the increase of the order of the magnetic field harmonics.When the thickness of large and small permanent magnet steel remains unchanged,and the width of large and small permanent magnet steel is 10 mm and 5mm respectively,the total harmonic distortion rate is minimum,the flux density distribution is maximum,and the magnetic field utilization rate is maximum.With the increase of the thickness of permanent magnet array magnetic steel,the amplitude of magnetic flux density also shows a wavy curve movement.When the thickness of large and small permanent magnet steel is the same as the width of large permanent magnet steel,the distribution of magnetic flux density is the largest,the total harmonic distortion rate is the smallest,and the utilization rate of magnetic field is the largest.