Initial Sizing of Tubular Linear Actuators Using Simplified Maxwell Stress Tensor Method

Abstract

This paper presents an innovative method for performing the initial sizing of tubular linear actuators (TLAs). Based on the Maxwell Stress Tensor (MST), an analytical expression is developed that allows the calculation of the force produced by a TLA in a quick and simple way. This expression can be employed for determining dimensional parameters considering the electric and magnetic loadings usually found in such electromagnetic devices. This technique can be applied to design slotless or slotted tubular linear permanent magnet synchronous motors (TLPMSM). In order to validate the developed method, four topologies of TLPMSM are considered. The calculated results of the developed analytical expression are presented and compared with results obtained by means of a magnetostatic finite element analysis (FEA). Additionally, the test results of a TLA prototype were used to validate experimentally the expression of force calculation by means of the MST method.