  Direct torque control is considered as one of the most efficient techniques
for speed and/or position tracking control of induction motor drives. However,
this control scheme has several drawbacks: the switching frequency may exceed
the maximum allowable switching frequency of the inverters, and the ripples in
current and torque, especially at low speed tracking, may be too large. In this
paper we propose a new approach that overcomes these problems. The suggested
controller is a model predictive controller which directly controls the
inverter switches. It is easy to implement in real time and it outperforms all
previous approaches. Simulation results show that the new approach has as good
tracking properties as any other scheme, and that it reduces the average
inverter switching frequency about 95% as compared to classical direct torque
control.
