Model Reference Adaptive System using Rotor Flux and Back Emf techniques for speed estimation of an Induction Motor operated in Vector Control mode: A comparative study

Abstract

Model Reference Adaptive System (MRAS) is a simple approach for speed estimation of an Induction Motor (IM). It is an attractive scheme for analysis especially when knowledge relating to system parameters are poor. The technique incorporates an error signal to be generated by comparing the output of the reference model (RM) and the adjustable model (AM), respectively. The error signal generated drives an adaptation mechanism (ADM) towards computation of speed. In this paper, an attempt has been made to compare two different methods based on the principle of MRAS for determination of rotor speed of IM operated in Vector Control (VC) mode. Speed estimated and the dynamics under various modes of operation in both MRAS strategies are compared. Analysis has been carried out in MATLAB environment using Sim Power System (SPS) and Simulink toolboxes in discrete time frame.