Simultaneous Estimation of Rotor Speed and Stator Resistance in Speed-Sensorless Vector Control of IMs

Abstract

In recent years, it is required to extend the operation regions of induction motors (IMs) even at low-speed in regenerating while maintaining a high control performance. Conventional rotor speed estimation methods using an adaptive flux observer are unstable at low-speed in regenerating, particularly near the zero frequency. In this paper, we propose a simultaneous estimation method of the rotor speed and the stator resistance to improve the control performance of the speed-sensorless vector control of IMs. In addition, we prove that the proposed estimation method is stable even at low-speed in regenerating. Furthermore, the effectiveness of the proposed method is demonstrated experimentally.