Research Article
Brain Emotional Learning Based Intelligent Decoupler for
Nonlinear Multi-Input Multi-Output Distillation Columns
M. H. El-Saify,
1
A. M. El-Garhy,
1
and G. A. El-Sheikh
2
1
Electronics, Communications, and Computers Department, Faculty of Engineering, Helwan University, Cairo, Egypt
2
Electronics and Communications Department, Pyramids High Institute (PHI) for Engineering and Technology,
6th of October, Giza, Egypt
Correspondence should be addressed to M. H. El-Saify; mhelsaify@hotmail.com
Received 27 August 2016; Revised 24 December 2016; Accepted 9 January 2017; Published 31 January 2017
Academic Editor: Asier Ibeas
Copyright © 2017 M. H. El-Saify et al. Tis is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Te distillation process is vital in many felds of chemical industries, such as the two-coupled distillation columns that are usually
highly nonlinear Multi-Input Multi-Output (MIMO) coupled processes. Te control of MIMO process is usually implemented via
a decentralized approach using a set of Single-Input Single-Output (SISO) loop controllers. Decoupling the MIMO process into
group of single loops requires proper input-output pairing and development of decoupling compensator unit. Tis paper proposes a
novel intelligent decoupling approach for MIMO processes based on new MIMO brain emotional learning architecture. A MIMO
architecture of Brain Emotional Learning Based Intelligent Controller (BELBIC) is developed and applied as a decoupler for 4
input/4 output highly nonlinear coupled distillation columns process. Moreover, the performance of the proposed Brain Emotional
Learning Based Intelligent Decoupler (BELBID) is enhanced using Particle Swarm Optimization (PSO) technique. Te performance
is compared with the PSO optimized steady state decoupling compensation matrix. Mathematical models of the distillation columns
and the decouplers are built and tested in simulation environment by applying the same inputs. Te results prove remarkable success
of the BELBID in minimizing the loops interactions without degrading the output that every input has been paired with.
1. Introduction
In chemical industries, distillation is one of the most impor-
tant processes. Te objective of distillation is to separate a
mixture of chemical components. Te purpose of control
is to maintain bottom and top product (distillate) purity
despite variations in feed fow and feed concentration. As
the distillation columns process is a MIMO system, many
researches utilize decentralized approaches to control it [1].
Te two-coupled distillation columns is a 4 input/4 output
process. Normally, control engineers decouple the process
into four independent loops via a decoupler [2]. Ten, every
loop is controlled separately by SISO controller [3]. Tis work
is aimed at proposing MIMO decoupling unit based on brain
emotional learning technique and applying it to the two-
coupled distillation columns.
Te design of intelligent systems is one of the most
growing felds that have received considerable attentions
in recent years. Biologically motivated intelligent control is
the discipline in which control algorithms are developed
by emulating certain characteristics of intelligent biolog-
ical systems. Many control techniques, such as artifcial
neural networks [4, 5], fuzzy control [6, 7], and genetic
algorithms [8, 9], had proven its efectiveness in solving
wide range of complex control problems. Recently, a new
member was added to this family of biologically motivated
intelligent control, which mimics the emotional learning
process in the limbic system of the mammalian brains.
Te model of brain emotional learning algorithm had been
proposed in [10, 11] and then was developed and shared for
control engineering applications [12]. Since then, BELBIC
is increasingly being utilized in many control engineering
applications such as electric motors [13, 14], servo systems
[15, 16], motion control [17, 18], and power systems [19, 20].
Some recent researches utilize other intelligent techniques in
cooperation with BELBIC to control the system such as fuzzy
logic [21, 22]. Tese applications had utilized BELBIC as a
SISO system. In [3], the two-coupled distillation columns is
Hindawi
Mathematical Problems in Engineering
Volume 2017, Article ID 8760351, 13 pages
https://doi.org/10.1155/2017/8760351