Indirect discrete-time sliding mode torque control of induction motors

In this paper the sliding mode technique is used to design a discrete-time control scheme for torque and flux tracking for induction motors. The controller is designed on the basis of an approximated nonlinear discrete-time model. First, the reference current vector is determined to impose the control objectives. Then, we propose a discrete-time sliding mode controller to force the motor currents to converge to the reference values. The rotor flux and the load torque are estimated by using a reduced order observer. The effectiveness of the designed control scheme is confirmed via simulations.