Sliding mode observer for vector control of induction motor

Vector control of induction motor is preferred as it gives independent control of flux and torque. For vector control knowledge of flux and speed is required. To eliminate the sensors, observers are used to estimate the flux and speed rather than measuring it. Sliding mode approach is popular due to its robust nature and very suitable for nonlinear system. This paper designs a sliding mode observers for speed control of induction motor. The sliding mode observer is verified experimentally. The experiment is carried out on a closed loop system consisting of induction motor, PI controller and the proposed estimator.