The Lyapunov-Based Estimator of Rotor Resistance for an ac Induction Motor

This paper proposes a novel methodology to estimate the rotor resistance for an ac 3-induction motor. The input of the estimator is derived by error function and model parameters. Associating with Lyapunov function, the controller drives estimation error to zero, and then a novel estimator for rotor resistance is successfully derived. Simulation results demonstrate the efficiency and robustness of the proposed estimator under load disturbance. The developed estimator will undoubtedly save not only the cost but also the maintenance of a servo system if the estimator is embodied in drive system regardless of the rising temperature when motor is running.