Sensorless second-order sliding mode control of Induction Motor

This paper presents the use of a higher order sliding mode scheme for sensorless control of induction motors (IM). The sliding mode approach is used both for control and for generating the rotor speed and the rotor flux estimates necessary for the controller, based only on the measurements of stator voltages and currents. The second order sliding mode control (SOSMC) is based on a super-twisting algorithm. Then, the proposed control scheme and the observer are tested on an experimental setup confirming their convergence properties. The used observer converges in a finite time and permits to give a good estimate of flux and speed even in presence of rotor and stator resistance variations.