IEEE Power Electronics Magazine - December 2014 - 4

From the Editor

by Ashok Bindra

Bringing Power Electronics
to the Edges of the Grid

e know that the rapid proliferation of renewable
energy sources and microgrids is making the power grid
more vulnerable to voltage fluctuations and variations. Managing these
variations with older electromechanically switched centralized command
and control systems is no longer practical and defeats any energy conservation goals. In fact, it requires a
decentralized approach with distributed and dynamic control capabilities.
And experts believe that this can only
be accomplished with semiconductorbased power electronic solutions that
can be deployed precisely along the
grid edge for the fast and granular control of voltage and VARs at hundreds
of points along the feeder. Lately, several companies have emerged to offer
grid-edge power electronic solutions
to solve this new set of challenges-
and the list is growing. As a result,
substantial data are now available
from the field that support the benefits
delivered by these solutions.
The first article in this issue,
"Power Electronics at the Grid Edge,"
is written by Deepak Divan, Rohit
Moghe, and Anish Prasai of Varentec
and discusses these challenges in
detail and also provides a solution.
In essence, the results demonstrated
in the article highlight the benefits
of applying power electronics at the

Digital Object Identifier 10.1109/MPEL.2014.2361473
Date of publication: 18 December 2014

IEEE POWER ELECTRONICS MAGAZINE

try to further push their performance
edges of the power grid. Although
envelope while newer chemistries
many researchers have proposed the
are in development
use of solid-state
simultaneously. As
transformers (SSTs)
Several companies
these chemistries
for the ultimate level
are being advanced,
of grid-edge control,
have emerged to offer
there is a tremendous
it is challenging and
grid-edge power
need for models that
requires high-voltelectronic solutions
can accurately preage wide-bandgap
to solve this new set
dict the behavior of
devices that are exof challenges-and
batteries. The secpensive and are only
the list is growing.
ond feature, by Nijust starting to behal Kularatna of the
come commercially
University Waikato,
available. In addiNew Zealand, emphasizes the need for
tion, meeting thermal-management,
better and more precise models based
fault-current, and no-field-service
on the internal electrochemistry of the
objectives is very demanding under
rechargeable batteries.
current design approaches, argue
In the "A Look Back" column,
the authors. As a result, even though
my article "Three-Terminal Linear
the concept of the SST continues to
Regulator Revolution Continues
be very appealing and is the focus of
Unabated" focuses on the evolution
much research, its translation into
of three-terminal linear regulators.
real products has not yet occurred.
Since their first introduction in 1969
Similarly, according to the article,
in the form of LM309 by National
the need to conform to the 100-kV
Semiconductor, linear regulators
basic impulse level requirement drahave weathered many storms and
matically impacts the size and cost of
continue to progress. This article
low-power converters (under current
investigates major milestones along
technology) to impractical levels.
their journey of 45 years.
Concurrently, with the advent of
The three regular columns, i.e.,
electric vehicles (EVs), mobile devices,
"Patent Reviews," "Entrepreneur
and backup systems, energy storage
Viewpoint," and "White Hot," bring
is gaining popularity. Consequently,
interesting and valuable information
rechargeable batteries and supercato the readers of the magazine. While
pacitors are growing rapidly. Though
the "Patent Reviews" column presents
mature chemistries such as lead-acid,
some tips on protecting and safeguardnickel-metal hydride, and lithium ion
ing trade secrets, the "Entrepreneur
have made significant progress, there is
Viewpoint" column describes relatively
a massive research effort in the indus-

 December 2014

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