An induction motor FEM-based comparative study: Analysis of two topologies

The most important component of electric traction chain is the traction motor, especially the Induction Motor `IM´ type for its multiple advantages such as the best reliability, reduced cost maintenance, ruggedness, higher efficiency reduced starting time compared to thermal motor traction and high starting torque. Rotor slot design of the IM for electric vehicle drives is investigated in this paper because improper rotor slot design will lead to bad torque performance of the IM. Calculations, using Finite Element Method `FEM´ analysis, for magnetic field density and magnetic flux are carried, by simulation using FEMM software in order to identify the IM parameters allowing the diagnostic of its defaults. In this paper, we present a comparative study of the two design structures of IM by varying the shape slots based on FEM. Simulation results prove that the optimal form of rotor slots is the round shape since the gain in torque ripple peak to peak may reach 40% compared to rectangular one.