Sensorless Vector Control of Induction Motor Stabilized at the Whole Region with Speed and Stator Resistance Identification based on Augmented Error

Abstract

This paper proposes new identification laws of an adaptive flux observer for speed sensorless vector controls. In speed sensorless vector controls of an induction motor with the adaptive observer, the speed identification system is known to be unstable in a part of regenerating region. In addition, it is pointed out that the stator resistance variation interferes with the speed identification. Thus it is necessary to find an adaptive scheme which can stabilize the identification system.
In this paper, firstly, the stability on the parameter identification is discussed from the viewpoint of Popov’s hyper stability. Secondly, identification laws for the speed and the stator resistance are proposed based on the new identification system which is derived by using the augmented error. Finally, effectiveness of the proposed method is shown by experiments.