Thermal analysis of an induction motor fed by unbalanced power supply using a combined finite element-symmetrical components formulation

In this paper, the authors study and analyse the thermal performance of a three-phase squirrel cage induction motor fed by asymmetrical power supply voltages with and without the neutral connected. Two load conditions and two different voltage dip situations were analysed. The steady-state temperature distribution in the motor was evaluated using a 2D finite element software package. Only thermal conduction and convection were considered. The thermal sources in the stator windings were evaluated from the measured currents. In the rotor bars, they were calculated using the symmetrical components method and the skin effect was taken into account. The iron losses were evaluated from the maximum flux density given by the manufacturer. The temperature numerical results are compared with experimental data obtained using an infrared data acquisition system