The main purpose of the thesis is to analyze and numerically model a three-phase induction motor with a triple squirrel cage. One of the main goals is to vary the geometrical and the material properties of the squirrel cage rotor bars, and to observe their influence on the resulting torque characteristic. The aim was also to investigate the effect of the squirrel cage manufacturing technology on the shape of the torque characteristic (die-cast aluminum cage or copper cage with welded short-circuit rings). In the first part of the thesis, the important characteristics of induction motors and the numerical method used to solve the electro-magnetic problem are described. The numerical analysis is performed in frequency domain using Flux Altair software. Based on 2D numerical calculations, we analyzed whether the triple squirrel cage could outperform the induction motors with conventional single or double squirrel cages in terms of rated, maximum and starting torque. Different models of the conventional single and double squirrel cages were built and compared to the results of the reference model with the triple squirrel cage. We also analyzed the magnetic flux density distribution and the corresponding stator currents. In the final part, numerical calculations were compared with analytical ones.
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