Sliding mode observer with parameter estimation for sensorless induction motor

Variable-speed drives are being continually innovated. Recently, sensorless induction motor drives have been much studied due to several advantages, and various sensorless algorithms for an induction motor drive have been proposed. Most sensorless control algorithms are based on the flux and speed estimations which are obtained from the voltage equations. Therefore, the sensorless control performance is largely influenced by the parameter errors of a motor. This paper investigates an improved sliding mode observer with the parameter error compensation for the speed sensorless control of an induction motor. The proposed parameter estimation is obtained from the error between the measured and decoupled currents. The performance of the proposed algorithm is verified through the simulation and experimentation.