Novel robust simultaneous estimation of stator and rotor resistances and rotor speed to improve induction motor efficiency

Abstract

This paper presents a novel method of parallel stator and rotor resistances and rotor speed estimation for robust sensorless induction motor drive. Moreover, the estimated parameters have been used to calculate the optimal rotor flux for improving the motor efficiency. In this scheme, a parallel model reference adaptive system (MRAS) is designed to simultaneous estimation of rotor speed and rotor-stator resistances in order to achieve a high-precise control in a wide range of motor speed. The aim of design of one MRAS for parallel estimation of stator and rotor resistances and rotor speed is to save the implementation cost and to reduce the processes time. Moreover, the stability of the control scheme has been derived based on Popov's criterion to design the adaptation mechanisms. Digital simulation based on Matlab/Simulink is carried out to evaluate the effectiveness of the proposed scheme at different operating conditions. The simulation results demonstrate the effectivity of the proposed scheme at a wide range of speed under load disturbance and parameter variation.