下载
Maxim > Design Support > Technical Documents > Application Notes > A/D and D/A Conversion/Sampling Circuits > APP 5776
Maxim > Design Support > Technical Documents > Application Notes > Metering and Measurement Markets > APP 5776
Keywords: smart grid, smart energy monitoring, electric power distribution
APPLICATION NOTE 5776
Smart Monitoring Improves Distribution-Grid Reliability
By:
David Andeen, Strategic Segment Manager for
Energy
Mar 07, 2014
Abstract:
Four broad trends are changing operating conditions on electric-power distribution grids, and thus increasing stress on
distribution infrastructure. To accommodate changing use models and improve reliability, smart powerline monitors are
necessary for utilities to track dynamic operating conditions on distribution grids.
A similar version of this article appeared December 4th, 2013 on EE Catalog.
Introduction
Four broad trends are changing operating conditions on electric-power distribution grids, and thus increasing stress on
distribution infrastructure:
1
.
Energy-use preferences have been shifting toward electric power, resulting in electricity-use growth rates, which are twice
that of other energy sources.
2.
Aging distribution equipment is now on average older than its manufacturers' recommended operating lifetimes.
3. Increasing use of electronic loads reduces load power factors and decreases grid utilization efficiency.
4
.
Distribution grids are no longer static one-way power delivery systems, but are now dynamic two-way links that also
connect distributed generation resources to loads.
To accommodate changing use models and improve reliability smart powerline monitors are necessary for utilities to track
dynamic operating conditions on distribution grids. Let's take a closer look.
Challenges for the Grid
Structurally, distribution grids have changed little over the past century. They developed to service comparatively modest, linear
loads over moderate distances. Until a few decades ago, that model was a realistic characterization of distribution grids'
operating conditions.
For the last several decades, however, electric-power use has been changing. According to IEC® (International Energy
Agency) estimates, worldwide electricity demand rose from 5.1PWh to 17.9PWh (1015 Wh) between 1973 and 2010.
1
Although
electric-energy use more than tripled over 37 years, it represents only a 3.44% compound annual growth rate (CAGR). It is also
more than double the CAGR of overall energy use, 1.69%, and of global population, 1.54%.
2
During the same time, most monitoring-technology deployments happened at generation and transmission facilities, with
monitoring on the distribution grid limited to the head end at the substation. Historical use models allowed utilities to assume
correctly that measurements at substations reflected operating conditions throughout the distribution grid. This assumption,
however, is in fact less valid because actual grid use has become more complex.
Upgrading the distribution infrastructure is expensive. According to a study commissioned by the EEI (Edison Electric Institute),
the cost for newly constructed overhead distribution lines ranges from $86,700 to $1,000,000 (U.S. $) per mile, depending on
Page 1 of 7
