On the Scaling of Consequent Pole Vernier Machines With Spoke Type Magnets

This paper thoroughly investigates the scalability problem of consequent pole Vernier machines having a spoke-type permanent magnet (PM) structure, with the aim to lay the basis of design of Vernier PM machines for various applications. The scalability analysis is carried out based on a generic analytical model, observations are obtained considering physics-based key design factors such as: machine geometries and dimensions, slot per pole per phase (SPP) value, magnet dimensions and associated induced air gap flux density. With the help of finite element analysis (FEA), the derived methodologies are verified with a consequent pole spoke type Vernier machine designed for low speed high torque direct drive application, comparisons are made between the analytical sizing equations and FEA calculations, the results suggest good agreement.