Techniques for modeling an induction motor with skewed slots with a time-stepping 2D-3D finite element method

This paper deals with the effect of rotor skewing in induction machines. Two cases of rotors with an identical number of bars but different skewing angles (0 and 10.23 degrees) are compared. This analysis is based on results obtained from real tests and 2D simulations and models performed with a new FLUX application called SKEW. Two approaches for the calculation of the skewed machine are presented: the N-slice model and the extruded model.

I. Introduction

This paper deals with the modeling of induction machines having a rotor with skewed slots; the model uses a 2D extruded approach within the finite element method. For this purpose, P. Dziwniel has proposed two approaches in [1] – [3]. Whereas he used the AV-A formulation for the 3D approach, we have used the electric vector potential and magnetic scalar potential formulation presented in [4], which requires a lower CPU time and less memory than the AV-A formulation.