Housed in an environmentally protected aluminum box, ATLAS II is capable
of sampling a large number of signals at once to characterize the inflow,
the operational state and the structural response of a wind turbine.
The ATLAS II has several key attributes that make it particularly
attractive for wind turbine deployment. It is small, highly reliable, can
operate continuously, uses off-the-shelf components, and has lightning
protection on all channels.
"The system provides us with sufficient data to help us understand how our
turbine blade designs perform in real-world conditions, allowing us to
improve on the original design and our design codes," said Jose Zayas, the
project lead, who has been working on ATLAS II since its inception in
1999.
Last year the ATLAS II team completed a project with GE Energy and the
National Renewable Energy Laboratory (NREL) to monitor the performance of
a GE wind turbine in a Great Plains site about 30 miles south of Lamar,
Colo., and will soon start monitoring a new work-for-others (WFO) project
with Texas Tech University.
The GE Energy/NREL/Sandia collaboration involved testing a 1.5-megawatt
(MW), 80-meter-tall turbine with a rotor diameter of 70.6 meters. GE
Energy is the largest wind turbine manufacturer in the U.S. and sells them
to developers -- such as Florida Power & Light -- all over the world. Wind
plant operators sell the electricity to utilities such as the Public
Service Company of New Mexico.
The GE turbine was equipped with four ATLAS II units, collecting a total
of 67 measurements, including 12 to characterize the inflow, eight to
characterize the operational state of the turbine and 24 to characterize
the structural response.
The system collected data continuously, 24 hours a day, seven days a week.
The four units were placed at various locations on the turbine, and a GPS
timestamp was used to maintain synchronization between the units. All data
streams from the different units were merged into a single data stream at
the base of the turbine where the ATLAS II software compressed the data
and stored them onto a local computer.
Data collection efforts began Sept. 14, 2004, and ended Jan. 19, 2005.
During that time, more than 17,000 data records were collected, for a
total of 285 gigabits (Gb) of data.
Because the turbine was located at a remote site, the data was transmitted
to NREL via a satellite link and later transmitted to Sandia. In places
where there is access to the Internet, the data can be monitored in real
time.
The Texas Tech project will start in August with an environmental
monitoring box being placed on a 200-meter meteorological tower at a test
site near the campus in Lubbock. The university is expected to eventually
erect a utility-size wind turbine. The ATLAS II will be used to collect
data from the machine.
Sandia also is planning three experiments, using the ATLAS II to monitor
the performance of three advanced blade designs on a test turbine it
operates in conjunction with the U.S. Department of Agriculture's research
station in Bushland, Tex.