Design Optimization and Performance Comparison of Two Linear Motor Topologies With PM-Less Tracks

An essential requirement for a long-stroke linear motion system is a low-cost and robust track. To allow the implementation of a linear motor topology in such application, passive tracks, consisting no rare-earth material, are recommended to reduce the price. This paper presents a comparison between two linear motor topologies with permanent magnet (PM)-less tracks: e.g., linear induction motor (LIM) and linear flux-switching permanent magnet motor (LFSM). These motors are benchmarked to a linear permanent magnet synchronous motor (LSM), which merits itself for high force density. The LIM and the LFSM are optimized for maximized continuous force while considering the same footprint as the LSM. The optimization is based on a multiphysical model containing an analytical representation of the magnetic field distribution, force production, power losses, and thermal the behavior of both structures. The obtained parameters are used to compare different configurations of both motors to the LSM. The results of the comparison show that at the price of higher losses, both topologies have comparable thrust force to the LSM.