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PREDICTIVE CONTROL WITH CON-STRAINTS, J.M. Maciejowski; PearsonEducation Limited, Prentice Hall, London,2002, pp. IX+331, price £35.99, ISBN 0-201-39823-0
For complex processes with time-delay effects,
a non-minimum phase behaviour, unusual dy-
namics or a multivariable system structure,
advanced techniques such as generalized predic-
tive control (GPC) or dynamic matrix control
(DMC) may be required to achieve better control
performance. For example, in the petrochemical
industries, the GPC method [1] has become one of
the most popular Model Predictive Control
(MPC) methods to be implemented. However, in
other industries and in more routine situations,
even though these advanced techniques may
provide superior control, they may not be used.
Implementing model-based control may also
require capital investment to support new hard-
ware and software products and also resources to
train personnel in the operational behaviour of
the new advanced controllers.
There are relatively few books devoted to
the subject of model predictive control. ‘Model
Predictive Control’ by Camacho and Bordons
[2], is one notable textbook contribution to
the Predictive Control bibliography. This is
an improved version of the monograph ‘Model
Predictive Control in the Process Industry’
by Camacho and Bordons [3], which was pub-
lished in the series ‘Advances in Industrial
Control.’ Recently Springer Verlag also pub-
lished the book ‘Applied Predictive Control’ by
Huang, Tan and Lee [4]. However, this review
concerns a new book by Maciejowski which
provides a good presentation of the state of the
art in Predictive Control. The book has been
organized as follows:
Chapter one presents a review of the historical
background of MPC and the motivation for
publishing the book. Also this chapter introduces
the main concepts involved in predictive control
such as the internal model, the reference trajec-
tory, a receding horizon and optimization.
Chapter 2 presents a standard formulation of
predictive control, which assumes the presence of
constraints, and of a multivariable plant. For this
purpose a state space setting is used. Offset free
tracking and stabilization of an unstable model
are discussed in the context of state observers.
Most of the interest in predictive control comes
from its ability to handle constraints. Chapter 3
considers how to solve on-line optimization
problems which arise in predictive control when
constraints are present. A major problem is the
possibility that the optimization becomes infea-
sible, and special strategies are needed for hand-
ling this situation. Chapter 3 includes an
explanation of how this can be done.
As is well known, the only information that
is really needed to implement a predictive
controller is the plant’s step response. Indeed the
original developments of predictive control
assumed a model in the form of a step response
[2, 3]. Some developments like GPC assumed
the model to be in the form of a transfer func-
tion. Chapter 4 deals with formulations of
predictive control based on step response and
transfer function models, and shows how these are
related to the state space setting used in the rest of
the book.
Many variations on the basic formulation of
predictive control are possible. For example, it is
possible to use other criteria than a quadratic one
for finding the optimal future input trajectory.
Also, it is possible to be creative when defining
required performance. These and other possibi-
lities are introduced in Chapter 5.
Nominal stability of the closed-loop system
with predictive control is discussed in Chapter 6.
It is assumed that an exact model of the plant is
available. Some methods such as, using terminal
constraints or distributing coincidence points
evenly along an infinite prediction horizon, are
introduced and discussed to adjust the formula-
tion and the tuning parameters so that closed-loop
stability is guaranteed.
In Chapter 7, the tuning problem of predictive
control is considered. Effect of the prediction
horizon, the time constant of the reference
trajectory and weights in the criterion are
investigated to adjust the controller.
Stability robustness of the predictive control is
addressed in Chapter 8. This issue is still at the
research stage.
In Chapter 9, predictive control is applied to
two well-known systems. First, the Shell heavy-oil
Copyright # 2003 John Wiley & Sons, Ltd. Int. J. Adapt. Control Signal Process. 2003; 17:259–263
BOOK REVIEWS 261
fractionator problem is considered and then the
effect of plant non-linearity is demonstrated by
applying the method to the Newell–Lee evapora-
tor model.
Chapter 10 addresses some wider perspectives
on predictive control such as the possibility of
constraint management within the predictive
control framework, the use of non-linear models
and the potential of the predictive control as a
basis for fault tolerant control systems.
Finally, descriptions of some predictive com-
mercial products, the software, which is used in
Chapter 1 and MATLAB’s Model Predictive
Control Toolbox, can be found in the appendices.
Summing up, this book is well organized. It
starts by introducing the different formulations of
predictive control and various methods used to
solve the on-line optimization problems, which
arise in predictive control with constraints, con-
tinues with nominal stability, nominal perfor-
mance and stability robustness issues for
predictive control and finishes with two case
studies. The theory of predictive control and
formulation of tuning parameters is presented and
practical issues are discussed.
There are many examples in each chapter of this
book that make the book easier understandable
for reader, particularly the novice reader. Also, at
the end of each chapter some exercises enable the
reader to assess their understanding of the
chapter’s contents. The predictive control toolbox
of MATLAB, which is common everywhere, has
been used to explain the solution procedures of
the examples and this makes the book much
better.
Most Model Predictive Controllers are formu-
lated based on the step response or transfer
function models but in this book the state space
model is used. This may make the material a little
strange for some readers. If a related CD were
included it would be easier for reader to follow the
material of the book.
Finally, the book is of interest for industrial and
process engineers who wish to apply modern
control in industry and also for researchers who
are interested in the recent progress in Predictive
Control.
MOHAMMAD H. MORADI
Faculty of EngineeringUniversity of Bu-Ali Sina
Hamadan, Iran
REFERENCES
1. Clarke DW, Mohtadi C, Tuffs PS. Generalisedpredictive control I & II. Automatica 1987; 23(2):137–160.
2. Camacho E.F, Bordons C. Model Predictive Controlin the Process Industry. Springer: London, 1995,ISBN 3-540-19924-1.
3. Camacho EF, Bordons C. Model Predictive Control.Springer: London, 1999; ISBN 3-540-76241-8.
4. Huang S, Tan KK, Lee TH. Applied PredictiveControl. Springer: London, 2002; ISBN 1-85233-338-3.
(DOI: 10.1002/acs.736)
SIGNAL PROCESSING SYSTEMS.THEORY AND DESIGN. N. Kalouptsidis,A Wiley-Interscience Publication, NewYork, 1997, pp XXI+840, price £75. ISBN0-471-11220-8.
Signals are an extremly important area that
covers many disciplines. Especially nowadays in
multimedia environments the signals like speech,
music and images need to be compressed,
encrypted, transmitted, stored, retrieved, filtered,
enhanced etc.
The book ‘Signal Processing Systems’ presents
the essentials of the signal processing (SP) that is
one of the most powerful technologies, which
have already been used in a wide range of fields
such as communications, medical imaging, remote
sensing, robotic systems etc. Each of these areas
needs deep development of digital signal proces-
sing (DSP) technology, with its own algorithms,
mathematics, and specialized techniques.
Copyright # 2003 John Wiley & Sons, Ltd. Int. J. Adapt. Control Signal Process. 2003; 17:259–263
BOOK REVIEWS262