Design of magnet arrays for permanent magnetic linear motor

Abstract

An iron-less single side permanent magnetic linear motor structure is presented, and two-dimensional analytical formulae for its magnetic field are deduced to design the types of magnetic arrays, the thickness of permanent magnet, and the duty ratio of magnet arrays, etc. With certain design parameters, conventional arrays are used instead of a piecewise Halbach arrays, and the machining and assembling of the motor are greatly simplified. Calculation results coincide with that of ANSYS. The analytical formulae can be used in designing cored linear motors by modifying boundary conditions. A linear motor driven bench with a single degree of freedom is realized, where the travel reaches 27 mm, the mass of the moving parts is 1.4 kg, and the maximum acceleration is 11.5 m/s².

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