Disturbance Torque Observers for the Induction Motor Drives

Abstract

The paper presents a comparative study on the performances of two disturbance torque observers in a induction motor drives. The first observer is a very simple one and is based on the mechanical system equation while the second one is a well-known observer, based on the reduced-order Gopinathâ??s method. To estimate the disturbance torque the electrical drive systems must be endowed with a low-resolution encoder and an acquisition system for the electrical variables, which helps to calculate the electromagnetic torque of the motor. The values of the estimated disturbance torque can be used, either for an instantaneous low-speed observer or for the control algorithm (feedforward control).