Magnetic field modeling of a linear permanent magnet motor with two isolated movers

Abstract

A novel permanent-magnet (PM) linear motor which composes of two isolated movers and one single stator is proposed in this paper. It is suitable for tasks requiring multiple drive motors. Each mover can produce independent force and flexible motions by interacting with the stator poles. Compared with conventional multi-motor driven system, it achieves more compact size, and thus increases the system force density. The design concept is presented. To facilitate fabrication and installation, the flat type PM linear motor with two isolated movers is proposed. The magnetic field model is formulated by using equivalent magnetic circuit (EMC) method. The influence of magnetization pattern and back iron is included in the analysis. Numerical computation is carried out to verify the analytical model. Comparison shows that the analytical model and finite element analysis (FEA) result match well. The employment of same-magnetization pattern and back iron helps to improve the force output. The similar concept of multi-mover and single-stator can be implemented into other electromagnetic machines.Index Terms -Linear motor, magnetic circuit, permanent magnet, finite element analysis.