Analytical and 3D FEM modeling of a tubular linear motor taking into account radial forces due to eccentricity

Electrical linear motors are electromechanical devices that produce short unidirectional or bidirectional strokes. The purpose of this work is to model a tubular linear motor (TLM) using 2D and 3D finite element (FE) method and analytical equations. The 2D and 3D FE magnetodynamic analyses are performed using a magnetic vector potential formulation. The linear displacement is modeled by means of a layer of finite elements placed in the air gap. The analytical model is obtained from a magnetic circuit formed by reluctances and magnetomotive forces. The topologies of these circuits change for each position of the mover. In this paper, the modeling of TLM is carried out focusing the optimization of analytical model and the calculation of radial forces in the presence of eccentricity. In addition, a comparison between simulated and measured performance on a motor prototype is reported.