Voltage vectorial control of an induction motor drive

The paper describes a vectorial control strategy for induction motor fed by VSI which allows to exploit the dynamic performances by taking into account both the rotor and stator time constant, and avoiding at the same time the use of current control loop. It is based on the step-by-step evaluation of the feeding voltage of the motor, in such a way as to achieve the imposed space vector of the stator current, corresponding to the reference values of the electromagnetic torque and flux. The strategy has been implemented on fully DSP-based control architecture for speed control of an induction motor drive. Experimental results are presented and compared with the ones obtained with an hysteresis current control loop. They show a very good behaviour of the system, both in dynamic and steady state operating conditions.