Direct Torque Control of an Induction Machine driven by a Matrix Inverter with Speed estimator (MRAS)

To advance the performance of AC adjustable speed system, this article proposes a strategy of direct torque control of induction machines fed by a three-phase matrix inverter. In addition to the control of torque and flux obtained with the DTC applied to a three-phase inverter with two levels, the matrix inverter application provides the control of an additional variable which is the input power factor. This process control allows to combine the advantages of the DTC with the advantages of the matrix inverter. The rotor speed is estimated by the model reference adaptive system scheme, which is determined from measured terminal voltages and currents. The MATLAB SIMULINK is used to perform the simulation.