jic.5.4.13839 Stability Analysis of a Three-Phase Induction Motor Drive using Variable Frequency Technique Mohd. Sarfaraz Alam M. Rizwan Khan Journal on Instrumentation and Control Engineering 2321–1148 5 4 1 9 10.26634/jic.5.4.13839 Three-Phase, Drive, Linearized Model, Stability, Analysis, Induction Motor, Matlab Codes This paper deals with the stability analysis of three-phase Induction motor drive using three stability criteria, namely Root locus, Bode plot, and Nyquist plot. etc. of the control system. The dynamic model of three-phase induction motor drive is designed. This model has been derived using two-phase motor in direct and quadrature axes. This approach is desirable because of the conceptual simplicity obtained with a two sets of windings, one on the stator and other on the rotor. The required transformation in voltages, currents, or flux linkages are derived in a generalized way. The mathematical equations so obtained are non-linear in nature. The mathematical model used is linearized around an operating point using the perturbation technique. The transfer function of three-phase induction motor drive is determined at different rotor frequencies and hence rotor speeds. The effect on stability of the drive is assessed at different frequency conditions. The rotor frequency (fr) and hence corresponding speed (wr =2πfr) at which the drive is unstable is reported. This analysis is carried out using MatLab codes. August - October 2017 Copyright © 2017 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=13839