IVSC-based speed estimation for an AC induction motor

Proposes a method which uses only Hall current sensor to estimate the velocity and flux of an AC induction motor. The integral variable structure control (IVSC) approach is firstly employed to design an observer such that the observer can track actual state of the plant and minimize the steady state estimation error. An adaptive speed estimator is synchronously designed by incorporating the switching function of variable structure system theory with a Lyapunov function. Simulation results demonstrate that the presented system has potential for both fast and accurate estimation of motor speed. Furthermore, the robustness of estimation system for resisting load disturbance and motor parameter variation is also guaranteed.