A Note on Stability Analysis Using Bode Plots

Authors

  • Juergen Hahn The University of Texas at Austin
  • Thomas Edison The University of Texas at Austin
  • Thomas F. Edgar The University of Texas at Austin

Abstract

Every chemical process control textbook states the Bode stability criterion in one form or another. But the stated definitions of the criterion are in almost all cases incomplete.  This not only influences the stability analysis of the system, but also has an effect on the gain and phase margins. In this paper the limitations of different versions of the Bode stability criterion are analyzed and a revised criterion is formulated.  This revised criterion results in a correct analysis for stability as well as robustness of the system. Examples are given to illustrate the importance of this revised stability criterion.

Author Biographies

Juergen Hahn, The University of Texas at Austin

Juergen Hahn was born in Grevenbroich, Germany, in 1971. He received his diploma degree in engineering from RWTH Aachen, Germany, in 1997, and his MS degree in chemical engineering from the University of Texas, Austin, in 1998. He is currently a PhD candidate working as a research assistant in chemical engineering at the University of Texas, Austin. His research interests include process modeling, nonlinear model reduction, and nonlinearity quantification.

Thomas Edison, The University of Texas at Austin

Thomas Edison is a lecturer at the University of Texas, Austin. He received his BE degree in chemical engineering from Annamalai University, his MTech degree from IIT Kanpur, and his PhD degree from the University of Maryland, College Park. His research interests include phase transition in liquid-liquid systems, equation of state close to critical point, and robust process control.

Thomas F. Edgar, The University of Texas at Austin

Thomas F. Edgar is Associate Vice President of Academic Computing and Instructional Technology Services at the University of Texas, Austin. He received his BS in chemical engineering from the University of Kansas and his PhD from Princeton University. He has concentrated his academic work in process modeling, control, and optimization, with over 200 articles and book chapters in addition to coauthoring two textbooks.

Downloads

Published

2020-06-23

Issue

Vol. 35 No. 3 (2001): Summer 2001

Section

Manuscripts