Sensorless high-order sliding modes vector control for induction motor drive with a new adaptive speed observer using super-twisting strategy

Abstract

This paper proposes a high-order super-twisting sliding mode control method applied to an induction motor fed by a power voltage source without speed sensor. Based on the vector control principle, high-order super-twisting sliding mode controllers in speed loop and flux loop are designed respectively. The super-twisting sliding mode control is utilised to improve the response speed and robustness of motor control systems. Meanwhile, high-order sliding modes are adopted to eliminate the chattering phenomenon. We also present the mechanism of adaptive super-twisting speed and rotor flux observers with the only assumption that from stator voltages and currents are measurable. The objective is to improve the speed control, the rotor flux control under load torque disturbances and parameter variations. The simulation results prove clearly a good robustness against load torque disturbances, the estimated fluxes and the rotor speed converge to their real values. Our study is close to reality; all the simulations are based on real models simulated within the Matlab SymPower System environment in continuous time.