The effects of various magnetic materials on lamination design for stator–rotor diecasting of induction motors for electric vehicle applications

Abstract

In this paper we describe a novel technique to model induction motors with a diecast stator and rotor and to examine the effects of various magnetic materials on the electrical performance of the motor. For electric vehicle applications, a high volume production operation of the electric motor requires the motor to be small and inexpensive. The expensive labor and material used to manufacture the motor encouraged the researchers to find new methods and techniques to reduce the cost and improve the performance. Diecast rotor and stator windings reduce motor cost and size. For diecasting induction motors, the motor laminations should be designed to optimize the electromagnetic field distribution over the cross section and along the axial direction. The magnetic material used for the laminations should also reduce losses and improve the overall efficiency. A 100 hp four-pole induction motor was modeled with finite elements, the field distribution, the magnetic flux density, and the mechanical performance of the motor were computed using nonlinear magnetostatic and complex steady-state eddy current techniques. The difference in the electrical and mechanical performance of the motor were evaluated for copper and aluminum diecasting. The results show that copper diecasting of the rotor and the stator of the induction motor with magnetic material properties and identified slotting shape is the way to achieve better motor performance and low cost operation.