Starting time calculation of large induction motors using their manufacturer technical data

Large high-voltage induction motors are widely used in industrial applications. Their accurate starting time is very much important for setting their over-current protective devices against heating and assessing power quality of distribution power system. In this paper, the starting time is accurately evaluated from a newly proposed technique that is employed to estimate electrical torque curve of induction motors from their manufacturer technical data. An accuracy of the proposed technique is validated by comparing the obtained starting times against those from precise time-domain simulation using full fifth-order model of induction motor. The comparative results mostly agree in satisfactory manner.