Torque Regulation by Means of Stator Flux Control for Induction Machines

The common characteristic of all direct torque control drives is the manipulation of stator flux by means of the application of an adequate stator voltage. In this work this concept is extended to the pulse width modulated of the correct stator voltage to achieve stator flux regulation and tracking of commanded torque. The strategy is based on a few simplified machine equations based on the principle that torque and load angle are related and that it is possible to control this angle in a rotor oriented coordinate system. High bandwidth control loop can be obtained using this method due to the absence of sources of uncertainty. Simulation and experimental results for a 4[kW] induction machine are presented.