Research On Modeling And Drive Optimization Of Magnetically Levitated Planar Actuator

In recent years,the era of the all things are interconnected is getting closer and closer to us.The development of the hardware industry represented by large-scale integrated circuits has laid the cornerstone for the smart future.In order to improve China's comprehensive national strength and maintain national security,it is necessary to independently develop large-scale integrated circuit manufacturing equipment.Based on the ultra-precision motion platform lithography machine,this paper studies the replacement object of the new generation of wafer stage-the modeling of the magnetically levitated planar actuator and the commutation method of the drive.Firstly,the basic structure and design principle of the planar actuator designed in this paper are briefly introduced.The two-dimensional Halbach array is used as the magnetic steel,and the assembled form and size of the magnetic steel are designed according to the actual conditions.The design of the coil winding portion is based on the motor drive method based on Lorentz force law,and its size and arrangement are determined.Subsequently,the decoupling model of the electromagnetic force and current was established under the condition that the planar actuator structure was determined.Firstly,an analytical model of the permanent magnet array is established,and the force model of a single coil in a magnetic field according to a certain placement mode is obtained under the condition that the magnetic induction intensity is known.According to the spin theory,the force decoupling model of the whole coil array is obtained.In order to verify the accuracy of the model,the magnetic field model and the single-coil force model were compared with the results of the finite element simulation.Finally,a corresponding commutation algorithm is designed for the overdriving structure of the magnetically levitated planar actuator.In order to reduce the thermal power consumption of the coil,the coil commutation method based on the gradient descent method and the heuristic optimization algorithm is proposed for a single fixed position.Then the S-curve is used as the realization goal of coil continuous trajectory commutation,and a norm-based commutation method is proposed.Among them,the 2 norm method and the infinite norm method can respectively contribute to the reduction of thermal power consumption and the limitation of maximum current.On this basis,combined with the idea of heuristic algorithm,a commutation method with improved 2 norm is proposed,which realizes the optimization of the current limit of the algorithm.The final simulation proves that the method can realize the commutation of the coil in the S-curve trajectory.