Title: Stability analysis of non-smooth optimisation-based controller design for CSTR using Kharitonov theorem

Authors: Bhawna Tandon; Shiv Narayan; Jagdish Kumar

Addresses: ECE Department, Chandigarh Engineering College, Ladran, Mohali, India; Electrical Engineering Department, PEC University, Sec-12, Chandigarh, India ' Electrical Engineering Department, PEC University, Sec-12, Chandigarh, India ' Electrical Engineering Department, PEC University, Sec-12, Chandigarh, India

Abstract: The paper presents the application of numerical solver H-infinity fixed order optimisation (HIFOO), for structured and fixed-order controller design to a feedback linearised continuous stirred tank reactor (CSTR). This solver constitutes a practical exploitation of the research in numerical techniques for non-convex non-smooth optimisation based on several techniques namely quasi Newton updating, bundling and gradient sampling that is implemented in a supporting package hybrid algorithm for non-smooth optimisation (HANSO) and results in the design of controller that is easy to implement. The reactor is considered to be an uncertain system on account of changes of concentration of input streams and reaction constants. The Kharitonov theorem is used to analyse the stability of the designed controller. Four Kharitonov polynomials are employed to analyse the robustness of the controller due to parametric uncertainties. Simulation results show the robust stability of the designed controller on account of changes of concentration of input streams and reaction constants of CSTR over the operation range.

Keywords: feedback linearisation; robustness analysis; H-infinity fixed order optimisation; HIFOO; Kharitonov theorem; continuous stirred tank reactors; CSTR; stability analysis; non-smooth optimisation; controller design; quasi Newton updating; bundling; gradient sampling; parametric uncertainties; simulation.

DOI: 10.1504/IJSCC.2016.076843

International Journal of Systems, Control and Communications, 2016 Vol.7 No.2, pp.151 - 163

Received: 02 Jul 2015
Accepted: 04 Jan 2016

Published online: 01 Jun 2016 *

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