International Journal of Applied Science and Engineering
Published by Chaoyang University of Technology

D. Krishnaa, K. Suryanarayanab, G. Aparnab, and R. Padma Sreeb,*

Department of Chemical Engineering, M.V.G.R. College of Engineering, Vizianagaram, India
Department of Chemical Engineering, Andhra University College of Engineering (A) Visakha-patnam, India

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Tuning Proportional Integral and Derivative (PID) controllers for unstable Second Order Plus Time Delay systems with a Zero (SOPTDZ), based on internal model control (IMC) and stability analysis (SA) principles is proposed. The controllers designed by the proposed methods are used to control unstable jacketed Continuous Stirred Tank Reactors (CSTR), carry-ing out irreversible first order reaction. The performance of proposed controllers is compared with the synthesis method. Simulation results on nonlinear unstable continuous stirred tank re-actors and transfer function models are presented to the show the efficiency of the proposed con-trollers.

Keywords: Internal model control; stability analysis method; synthesis method; CSTR; PID controller; Unstable systems; Second Order Plus Time Delay system with a Zero (SOPTDZ).

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Received: 2011-05-24
Revised: 2011-07-02
Accepted: 2011-09-29
Available Online: 2012-03-01

Cite this article:

Krishna, D., Suryanarayana, K., Aparna, G., Sree, R.P. 2012. Tuning of PID controllers for unstable continuous stirred tank reactors. International Journal of Applied Science and Engineering, 10, 1–18.