A comparative study on the starting methods of three phase wound-rotor induction motors

This paper presents a comparative study on the starting performance of three-phase wound-rotor induction motors under different methods of starting. These methods are online direct starting, variable rotor resistance starting, and double-feed starting. In double-feed starting, the rotor winding is connected in parallel with the stator winding across the supply for a predetermined short period. By this connection, the motor produces an extremely high starting torque. For carrying out the investigations sought, a rigorous state space mathematical model has been developed and simulated. The effect of torsional dynamics has been taken into considerations.IEE