Design and finite element analysis of high-density torque induction motor for traction applications

The paper presents the design and FEM simulation of a novel induction motor intended as a specialized drive for electric traction and/or airborne propulsion applications. Several particular requirements related to the size, weight and dynamics did rise non-conventional challenges and therefore a less-than classical approach have been considered. The proposed solution consists in a combination of an external rotor mated with an internal stator with ring coils. Furthermore, the coils arrangement may be reconfigured on-the-fly, allowing operation with two distinct synchronous speeds (different number of poles), solution which largely fulfills all the requirements.

I. Introduction

Lately, there is an indubitable concern for the increase of torque density of the electric machines. Obviously it is not about general utility (industrial) motors but units dedicated to special purposes. Without any doubts, electric traction (when it comes to road vehicles) or propulsion of airborne vehicles represent applications in which the torque density always was (and still is) a fundamental limitation. Historically, a plethora of non-conventional solutions have been investigated, among them multiphase machines or HT superconducting motors being the most considered.