Performance analysis of twin induction motors with field oriented control

The objective of this research is to study the performance of twin inductionmotors with field oriented control. This type of control is usually controlthe spatial orientation of the electromagnetic fields in the machine, tomaintain 90 spatial orientation between stator and rotor fields. Then themachine will develop high torque per ampere. Two identical wound rotor3-phase induction machines are used in tins work for field orientation of 3-phase wound rotor induction motors . Three different methods for fieldorientation of the two identical motors are achieved ,In the First method, the two stator windings are connected in parallel tothe supply and tile two rotor windings are connected together in series.The two rotors are mechanically coupled by different angles of the tworotor axes. The two stator rotating fields are in the same direction ofrotation. TIns method of connection is remarked by system (A) .Theexperimental and computed results show that the motor fields can beoriented by 90 degrees ,when the rotor is injected by an external voltage,shifted by a time angle would be varied with speed variation. When thisinjected voltage is shifted by a constant angle through the speed variation,a suitable value of tins angle can be improve tile field angle to about 90 .This suitable angle is chosen to be 120 degree, in which the motor fullload torque is increased to 1.11 times that the conventional rated torquewithout any increasing of motor losses.III tile second method, the two stator windings are connected in series tothe supply and the two rotor windings are connected together in series Thetwo rotors are mechanically coupled by different angles of tile two rotoraxes. The two stator rotating fields are in the same direction of rotation.This method of connection is remarked by system (B). from tile analysisof this system ,it is shown that tile magnitude of injected voltage will be