IEEE Power Electronics Magazine - December 2014 - 46

White Hot

(continued from p. 48)

I have a colleague who really likes Maple and encourages me to give it a try.
I have looked at Maplesoft's Web site
and have to admit it looks very interesting. Maybe while I am still a student I
should buy the student version and see
how Maple works for me.
There are some problems that just
seem to be solved best using a program to do the calculations. Mathcad
has built-in programming functions,
and I use those from time to time for
small programs (like ten to 12 lines of
code). At one time, I would write programs in C for more complicated engineering calculations. Today, I generally use MATLAB when I need to
solve a problem by writing a program.
I know there are engineers that love
MATLAB, like my professors, but I
still find it a little difficult to use. I do
recognize its power and flexibility, so
it is the right tool from time to time.
One area where MATLAB is really useful to me is control design using add-ons like the control toolbox.
The ease with which it can work with
transfer functions and plot results in
various ways, such as both the Bode
and Nyquist plots, has been very useful to me in several projects.

IEEE PowEr ElEctronIcs MagazInE

Also available for those who like
MATLAB is the open-source program GNU Octave. As I understand,
Octave has most of the capability of
MATLAB but at no cost. One drawback for me is that Octave is best
on a Linux platform, and I mainly
use Windows. There is a version of
Octave compiled for Windows, and
checking it out is somewhere in my
very long to-do list.
The usefulness of MATLAB is extended when the graphical interface,
Simulink, is added to the mix. In one
project, I collaborated with a client
on the design of a digital controller
for a point-of-load converter. We used
MATLAB and Simulink to study various algorithms and implementations,
such as the direct and transposed
forms of the digital filter used as a
compensator. We were also able to
study the performance of the compensator with various bit lengths.
With the design complete in MATLAB
and Simulink, the client was able to
directly generate a programming file
for an FPGA. When we ran the converter using the digital controller in
the FPGA, the experimental results
exactly matched our simulations, in-

z December 2014

cluding some slightly chaotic behavior during extreme load transients.
At this point, by talking about Simulink, we have crossed the boundary
from calculation to simulation, which
will be the topic for my next column.

About the Author
Robert V. White (bob.white@ieee.
org) is an IEEE Fellow and has over
30 years of industry experience as a
power electronics engineer. He has
worked in product design, systems
and applications engineering, and
technology development. He has been
an active volunteer with the IEEE
Power Electronics Society, serving
several years on the Administrative
Committee, two terms as technical
vice president, and as a Chapter chair.
He earned a B.S.E.E. degree from the
Massachusetts Institute of Technology and an M.S.E.E. degree from
Worcester Polytechnic Institute. He is
currently pursuing a Ph.D. degree in
power electronics at the University of
Colorado-Boulder. Presently, he is
the chief engineer of Embedded
Power Labs, a power electronics consulting company.

Table of Contents for the Digital Edition of IEEE Power Electronics Magazine - December 2014