On the Temperature Control for a Test Case Short Pipe Network
Central Heating System
Nikolaos D. Kouvakas and Fotis N. Koumboulis
Halkis Institute of Technology, Department of Automation, 34400 Psahna Evoias, Greece
Keywords: Central Heating Systems, Temperature Control, Autonomous Heating, Dynamic Controllers.
Abstract: In the present paper the mathematical representation of a test case central heating system with a short pipng
network, three radiators and one boiler heating two apartments is developed in the form of a nonlinear
model. A linear dynamic controller achieving independent apartment temperature control and being
unaffected from the external temperature is proposed. The controller is developed on the basis of a linear
approximant. The closed loop performance is tested through simulations on the original nonlinear model.
1 INTRODUCTION
The problem of modelling and control of central
heating systems has attracted considerable attention
during the last years (see Cai, 2006; Hansen, 1997;
Koumboulis et al., 2007; Koumboulis et al., 2008a
and b; Koumboulis et al., 2009a,b and c;
Koumboulis and Kouvakas, 2010; Mendi et al.,
2002; Morel et al., 2001; Zaheer-Uddin et al., 1994;
Zanobini et al., 1998 and the references therein).
Significant attention has also been given to the
modelling of core components of central heating
systems as well as to the application of different
control techniques to regulate the performance
variables. These techniques range from classical and
metaheuristic controllers, fuzzy control schemes,
adaptive controllers, optimal controllers to multi
delay dynamic controllers satisfying transfer matrix
design requirements. In the present paper the
mathematical representation of a test case short pipe
network central heating system including two
apartments is presented in the form of a nonlinear
model. The first apartment has one room while the
second is considered to have two rooms. The system
consists of a short piping network, three radiators, a
boiler and three rooms. The main difference between
the present model and those in Koumboulis et al.,
(2007), Koumboulis et al., (2008a and b),
Koumboulis, Kouvakas and Paraskevopoulos
(2009a-c), and Koumboulis and Kouvakas (2010) is
the length of the pipes. The transport delays are
small and so they do not significantly to influence
the behavior of the plant. Thus, the present
mathematical representation does not incorporate
time delays. Furthermore, the first and the second
room of the second apartment are coupled via direct
heat exchange. A linear dynamic controller
achieving independent apartment temperature
control and being unaffected from the external
temperature is proposed. The controller is developed
on the basis of a linear approximant. The closed loop
performance is examined through simulations on the
original nonlinear model.
2 MODEL OF THE SYSTEM
In the present section the mathematical model of the
test case central heating system, will be presented. It
is similar to that proposed in Koumboulis et al.,
(2007), Koumboulis et al., (2008a and b),
Koumboulis et al., (2009a, b and c), and
Koumboulis and Kouvakas (2010). The system
consists of the piping network, three radiators, a
boiler and three rooms. In each room one of the
radiators is installed. The main difference between
the model developed here as compared to those
presented in Koumboulis et al., (2007), Koumboulis
et al., (2008a and b), Koumboulis et al., (2009a-c),
and Koumboulis and Kouvakas (2010) is that small
length pipes are used. Thus, the transport delays are
small and so they can be neglected. Furthermore, the
two rooms of the second apartment are considered to
be coupled via direct heat exchange. Let
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D. Kouvakas N. and N. Koumboulis F..
On the Temperature Control for a Test Case Short Pipe Network Central Heating System.
DOI: 10.5220/0004048506220627
In Proceedings of the 9th International Conference on Informatics in Control, Automation and Robotics (ICINCO-2012), pages 622-627
ISBN: 978-989-8565-21-1
Copyright
c
2012 SCITEPRESS (Science and Technology Publications, Lda.)