Performance Evaluation of Three-Phase Induction Motor Fed by unbalanced voltage Combined with Over- or Under Voltage Using Finite Element Method

Unbalanced voltages can exist anywhere in a three-phase power distribution system. Thus, investigation of their effects on power system equipments, especially three-phase induction motors as most commonly used type of electric motors, is vital. This paper presents performance evaluation of a three- phase squirrel cage induction motor under unbalanced voltage combined with over- or undervoltage based on Finite Element Method (FEM) simulation. To achieve this purpose , number of unbalanced voltages with averages equal to 90, 100 and 110% of rated voltage is applied to FEM simulation model of the motor and its steady state operating performance has been analyzed and the resulted input/output power, losses, efficiency and torque have been discussed. The employed measure for voltage unbalance in the present work is complex voltage unbalance factor (CVUF) that consists of voltage magnitude and angle.