High performance Direct Torque Control for induction motors using an adaptive sliding mode observer

The principal objective of this work is to show that the performance of the control techniques well known like the Direct Torque Control, can be improved by the introduction of an adaptable state observer structure to estimate variables that cannot be easily measured like the magnetic flux and torque; and that also, allow at the same time to know the stator resistance of the three phase squirrel cage induction motor, indispensable for their control using the DTC scheme. The secondary objective consists on developing a control strategy that allows limiting the current that is presented in the motor start, since this can be from 6 to 8 times the nominal current, which originates that the power devices are subjected to big efforts.