Speed estimation of an induction machine based on designed Lyapunov candidate functions.

This paper describes a new approach to estimate speed of the induction machine from measured terminal voltages and currents. In this approach, the speed is assumed to be unknown constants, because it changes slowly compared to electrical variables such as currents and fluxes. Based on this assumption, a state observer is defined to eliminate the flux information of the machine. Then, a Lyapunov function and a new candidate expression for the time derivative of Lyapunov function that guaranties the stability conditions of the system dynamics are developed from which the speed of the machine is derived. The proposed system is analyzed and verified by both simulation and experiment. [ABSTRACT FROM AUTHOR]