VECTOR-CONTROLLED-INDUCTION-MOTOR-DRIVE

Controlling An Induction Machine

Vector controlled 3 level VSI –fed IM can be used for the rotor side control of IM, which is more beneficial than its preceders. Rotor side control of IM permits the control of voltage, current, active power and reactive power. In the proposed scheme the rotor is fed through a 3 level VSI which gets its switching pulses by SPWM technique. Direct vector control method is adopted and rotor and stator parameters are converted from rotating reference frame to synchronous reference frame which provide precise independent control of both the active and reactive power which is to be studied. By this technique it is possible to operate the IM in 4 quadrants -sub synchronous & super synchronous generating and sub synchronous & super synchronous motoring. This method finds its application where an IM is to be operated as a generator supplying power to the grid. The simulated response of an induction motor will be presented in different modes of operation.