This book focuses on the study and development of one of the most
advanced topics in broadband wireless communications systems:
power efficiency and power consumption in wireless communications
systems, especially of mobile devices. Hence, the main focus of this
book is on the most recent techniques for the conservation of power
and increase in power efficiency.
December 2007, San Jose, California: It seems a long time ago.
I walked into a big networking company to head their small
Power over Ethernet (PoE) applications team. Surprisingly,
I hardly knew anything about PoE prior to that day, having been a
switching-power conversion engineer almost all my life. But it
seemed a great opportunity to widen my horizons. As you can see,
one notable outcome of that seemingly illogical career choice five
years ago is the book you hold in your hands today. I hope this small
body of work goes on to prove worthy of your expectations and also
of all the effort that went into it. Because, behind the scenes, there is a
rather interesting story to relate—about its backdrop, intertwined
with a small slice of modern PoE history, punctuated by a rather res-
tive search for our roots and our true heroes, one that takes us back
almost two centuries
Modern day large power systems are essentially dynamic systems with stringent
requirements of high reliability for the continuous availability of electricity.
Reliability is contingent on the power system retaining stable operation during
steady-state operation and also following disturbances. The subject of power sys-
tem stability has been studied for many decades. With new developments, and there
have been many over the past couple of decades, new concerns and problems arise
that need to be studied and analysed. The objective of this book is a step in that
direction though not ignoring the conventional and well-established approaches.
The electrical power grid is often referred to as one of the most complex man-
made systems on Earth. Its importance to all aspects of our daily lives, economic
stability, and national security cannot be overstated, and the need for an updated,
secure, resilient, and smarter power grid infrastructure is increasingly recognized
and supported by policy makers and market forces.
For many years prior to the 1970s, engineers designed and built switch mode
power supplies (SMPSs) using methods based largely on intuitive and exper-
imentally derived techniques. In general, these power supplies were able to
achieve their primary goal of high-efficiency power conversion; unfortu-
nately, due to the lack of adequate theoretical analysis techniques, many of
these power supplies only marginally met their desired performance require-
ments. In many cases, they were considered to be unreliable.
Thepredecessorvolumeofthisbookwaspublishedin1996.Intheyears
since then, some things have changed and some have not.
Two of the things that have not changed are the desire for better
models and faster simulations. I performed the original simulations on
my “hyperfast” 133-MHz computer! At the time, I thought if I could just
getafastercomputer,allofourSPICEproblemswouldbehistory,right?
TodayIamsimulatingonacomputerthathasa2.6-GHzprocessorwith
512 MB of RAM, and I would still say that simulations run too slow.
The computer technology has evolved, but so have the models. In 1996
wewereperformingsimulationson100-kHzpowerconverters,whereas
today I routinely see 1- and 2-MHz power converters.
I am presenting this novel book on advances and trends in power electronics and motor
drives to the professional community with the expectation that it will be given the same
wide and enthusiastic acceptance by practicing engineers, R&D professionals, univer-
sity professors, and even graduate students that my other books in this area have. Unlike
the traditional books available in the area of power electronics, this book has a unique
presentation format that makes it convenient for group presentations that use Microsoft’s
PowerPoint software. In fact, a disk is included that has a PowerPoint file on it that is
ready for presentation with the core figures. Presentations can also be organized using
just selected portions of the book
n recent years, there have been many books published on power system optimization.
Most of these books do not cover applications of artifi cial intelligence based methods.
Moreover, with the recent increase of artifi cial intelligence applications in various fi elds,
it is becoming a new trend in solving optimization problems in engineering in general
due to its advantages of being simple and effi cient in tackling complex problems. For this
reason, the application of artifi cial intelligence in power systems has attracted the interest
of many researchers around the world during the last two decades. This book is a result
of our effort to provide information on the latest applications of artifi cial intelligence
to optimization problems in power systems before and after deregulation.
