Optimisation method of magnetic levitation actuator for rotary table

Abstract

This study presents a general optimisation method for determining the dimensions of the magnetic levitation (maglev) actuator for rotary tables. Combined with an improved electromagnetic numerical model of the maglev rotary tables, the optimal thickness dimensions of coils and magnets are obtained by the evolutionary optimisation algorithm. Different from the existing magnetic force model built by the harmonic analysis method, the improved numerical model involves the clearances of the neighbouring magnets in the circular magnet array and applies the numerical integration method to solve the complex Lorentz integrals. According to the evaluation function based on the numerical force model, the optimal thickness dimensions are determined via an evolutionary optimisation algorithm. By this method, the size of coils and magnets in the rotary table with the circular Halbach magnet array can be determined accurately and directly, rather than obtaining a single structure dimension by an analytical approach. In this work, the method is applied to optimise the dimensions of a maglev rotary table, and a prototype is manufactured according to the obtained optimal parameters. The experimental and simulation results verify the accuracy and validity of the proposed optimisation design method.