Design and Analysis of a Linear Permanent- Magnet Vernier Machine With Improved Force Density

This paper proposes a novel linear permanent-magnet (PM) vernier machine, which offers high force density, high efficiency, simple structure, and low cost. The novelty of the proposed machine is substantiated by integrating appropriate magnetization directions of PMs in the armature core. First, the structure and the operation principle of the proposed machine are descried. The machine is subsequently designed for a given set of specifications and its electromagnetic performances are analyzed by time-stepped transient finite-element method. An analytical equation is derived for evaluation of the thrust force ripple. Finally, experiments on a prototype of the proposed machine are carried out for validation.