The main objective of the thesis was to build a numerical model of an induction motor with Dahlander winding connection. The operation of the motor was analyzed based on numerical calculations of the magnetic flux density distribution, torque characteristics, mechanical power and efficiency. The introductory part lists the areas of application of the analyzed motor, its main features, advantages (with an emphasis on the possibility of changing the number of pole pairs) and drawbacks of the Dahlander winding connection (with an emphasis on the poor winding factor). Based on the literature review a comparison is provided between the analyzed motor and conventional induction motors. The central part of the thesis presents the numerical results obtained with the magnetic analysis in frequency and time domain. First, the comparisons of the calculated static torque characteristics, mechanical power, and efficiency for different numbers of pole pairs have been performed. Second, the torque pulsations, the transient phenomena during the switching of the pole pairs and the influence of different numbers of rotor bars on the machine's output characteristics have been investigated. In the final part of the thesis, the suggestions for upgrades and improvements of induction motors with Dahlander winding connection have been provided.
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