AMSC’s STATCOM Replaces SVC at Ergon Energy
A Case Study by AMSC • September 2012
The Background
Ergon Energy is an Australian electricity
distributor, retailer and generator, servicing
around 680,000 customers across an
operating area of over one million square
kilometers – 97% of the state of
Queensland. Despite the presence of a
static VAR compensator (SVC) at one of
the area substations, this utility had begun
experiencing voltage stability problems in its
network around St. George, which is
situated 500 kilometers inland of Brisbane
on the Balonne River in southern
Queensland. By utilizing AMSC’s D-VAR®
system, Ergon was able to resolve these
instability issues while also retiring the SVC
system.
The Problem
Ergon Energy was utilizing an aged SVC that was experiencing occasional outages and failures at
its St. George substation, which is located in a remote area and is served by a single, 194 kilometer
subtransmission feeder operating at 66 kilovolts. This SVC system was exposing the surrounding
grid to significant voltage fluctuations caused in part by switching of large commercial farming,
cotton gin and pump loads. In order to continue managing power quality in the surrounding area,
the SVC system required replacement with a solution that was able to normalize system voltages
to acceptable levels at all times and was also able to be expanded to meet future VAR
requirements.
AMSC’s Analysis
AMSC’s Network Planning and Applications Group performed a series of studies for Ergon Energy
to determine the solution’s optimal/desired:
• Dynamic performance
• Harmonic performance
• Grid impact
These studies determined that a hybrid solution consisting of STATCOMs and capacitors would be
the optimal approach to meet Ergon Energy’s cost and performance perspective requirements.
Classified as a Flexible AC
Transmission Systems (FACTS)
device, AMSC’s D-VAR STATCOM
utilizes the company’s proprietary
and advanced control and
monitoring algorithms that detect
and instantaneously compensate
for voltage disturbances by
injecting leading or lagging
reactive power (VARs) precisely
when and where it is needed. The
reactive power is generated by
AMSC’s proprietary four-quadrant
IGBT inverters that are capable
of fully injecting capacitive or
inductive VARs in one line cycle.
The system’s full dynamic
capability of 2.67 times its rated
output can be provided for up
to two seconds.
The Solution
In order to resolve the customer’s requirements in the most cost
effective manner, AMSC developed a solution that coupled the
company’s D-VAR STATCOM systems with multiple capacitor
banks, step-up transformers and a master plant controller. The
total system had a continuous rating of more than 20 MVAr
capacitive and 5 MVAr inductive and a dynamic rating
of more than 15 MVAr. The inherently modular and flexible
characteristics of AMSC’s solution allows for additional D-VAR
units and capacitor banks to be added to the system in the
future if/when changes to the area load increased VAR support
requirements. AMSC completed a turnkey installation and
commissioning of this system as well as decommissioning of
the old SVC in 2012. AMSC continues to provide ongoing
maintenance and support services to Ergon Energy.
“We were very pleased
with AMSC’s responsiveness and
professionalism from pre-sale through
implementation. AMSC continues
to provide ongoing maintenance and
support services to Ergon Energy”
Stephen Arthur,
Substation Design Engineer
External, Ergon
About AMSC
www.amsc.com
© 2012 AMSC. AMSC, D-VAR, GRIDTEC SOLUTIONS,
SMARTER, CLEANER … BETTER ENERGY, are trademarks
or registered trademarks of American Superconductor
Corp. or its subsidiaries.
ERGN_CS_0912
AMSC (NASDAQ: AMSC) generates the ideas, technologies and solutions that meet
the world’s demand for smarter, cleaner … better energy. Through its Windtec
Solutions, AMSC provides wind turbine electronic controls and systems, designs and
engineering services that reduce the cost of wind energy. Through its Gridtec
Solutions, AMSC provides the engineering planning services and advanced grid
systems that optimize network reliability, efficiency and performance. The
company’s solutions are now powering gigawatts of renewable energy globally and
enhancing the performance and reliability of power networks in more than a dozen
countries. Founded in 1987, AMSC is headquartered near Boston, Massachusetts
with operations in Asia, Australia, Europe and North America.