A Method for Correcting Voltage Errors in a V / f Controlled Induction Motor Using Disturbance Observers

Abstract

This paper proposes a method for compensating voltage errors using a parallel disturbance observer and a current controller for V / f control in the d-q rotational frame. The parallel disturbance observer uses a fast-responce observer and a slow-responce observer to separate the back electromotive force (EMF) from the estimated disturbance voltage. The voltage error is thus efficiently corrected using the proposed method. The proposed method is validated on the basis of the experimental results. This method can be used to decrease current distortion to less than 1/9 that observed in the conventional method.