Characterization of a High Speed 24 kW Class Squirrel-cage Induction Motor for Electric Vehicles

This paper presents a possible application of squirrel-cage induction motor (IM) for electric vehicles (EVs). First, we have fabricated a 24 kW class high speed IM, and then characterized it based on experiment, finite element method (FEM) analysis, and equivalent circuit analysis. We have confirmed in experiment that the maximum efficiency of the IM reaches 91.3% at 8000 rpm. We have also verified by FEM analysis and equivalent circuit analysis that much higher efficiency can be realized by modulating slip, input frequency, and input voltage. We have succeeded in searching the optimum condition achieving the maximum efficiency.