First order Robust Controller Design for the Unstable Process with Dead Time

Thirunavukkarasu, I and George, V I and D’Souza, Jeane Maria and Shanmugapriya, S and Iyer , Narayan S (2011) First order Robust Controller Design for the Unstable Process with Dead Time. Journal of Emerging Trends in Engineering and Applied Sciences (JETEAS), 2 (1). pp. 117-122. ISSN 2141-7016

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In this paper, the problem of stabilizing a given but arbitrary linear time invariant continuous time system with the transfer functions P(s)= N(s)/ D(s), by a first order feedback controller C= x1s + x2 / s + x3 was taken. The complete set of stabilizing controllers is determined in the controller parameter space [x1, x2 , x3] . This includes an answer to the existence question of whether P(s) is “first order stabilizable” or not. The set is shown to be computable explicitly, for fixed 3 x .The results to stabilize lower order plants is extended to determine the subset of controllers which also satisfy various robustness and performance specifications. The problem is solved by converting the H∞ problem into the simultaneous stabilization of the closed loop characteristic polynomial. The stability boundary of each of these polynomials can be computed explicitly for fixed x3 by solving linear equations. The union of the resulting stability regions yields the set of all set of all X1 and X2.The entire three dimensional set is obtained by sweeping X3 over the stabilizing range. They demonstrate that the shape of the stabilizing set in the controller parameter space is quite different and much more complicated compared to that of the PID controllers.

Item Type: Article
Uncontrolled Keywords: lower order h-infinity, PID controller, hurwitz criteria, robust performance, inverted pendulum
Subjects: Engineering > MIT Manipal > Chemical
Engineering > MIT Manipal > Instrumentation and Control
Depositing User: MIT Library
Date Deposited: 10 Jan 2012 10:46
Last Modified: 13 Sep 2014 04:26

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