On the Selection of the Commutating Instants in Induction Motor Drives

The main auxiliary phenomena are considered which arise in the drives using a frequency-controlled induction motor supplied by a three-phase bridge inverter as an actuator. Particularly, three quality indexes connected with these phenomena are taken into account and, for different drives, the commutating instants, which separately optimize the quality indexes, are determined. Lastly, a comparison among the optimum values of the quality indexes makes it possible to obtain simple variation laws of the commutating instants, which shows the overall behavior of the drive.