Rotor Speed Observer with Extended Current Estimator for Sensorless Control of Induction Motor Drive Systems

Abstract

The aim of paper is to investigate an efficient sensorless control method with vector-control technique for the induction motor (IM) drive systems. The proposed technique relies on the indirect rotor-field orientation control scheme (IRFOC). All sensorless control techniques are greatly affected by the observation of the speed estimation procedure. So, an efficacy new algorithm for estimating the rotor speed of the adopted machine is proposed. In addition, a simple effective method to estimate the machine rotor currents is suggested. The adopted rotor-speed observer is based on the concept of IRFOC method and the phase-axis relationships of IM. To ensure the capability of the proposed sensorless speed-control system, a simulation model is developed in the MATLAB/Simulink software environment. The robustness of the new control method is analyzed under parameter uncertainty issue. Furthermore, comprehensive experimental results are obtained. The whole obtained results confirm the validity of the proposed observer for sensorless speed control capability. The given results also verify the effectiveness of the suggested sensorless control system-based IRFOC for speed-control drive systems of IM. Moreover, the results assure that the presented rotor-speed observer is effectively robust via any parameter changes.

Keywords

• induction motor (IM)
• indirect rotor-field orientation control (IRFOC)
• rotor current estimation
• rotor-speed observer
• sensorless vector control strategy