FrogE-TECH

Un couplage de géants:

In a coupling of giants recently, the 2.5-megawatt dynamometer at the U.S. Department of Energy's National Renewable Energy Laboratory blasted 12.6 million inch pounds of torque at Samsung's 185,000-pound wind turbine drive train.

The King Kong of wind turbines battled the Godzilla of dynamometers to a draw.

It was the greatest amount of power ever measured at NREL's dynamometer lab, and the largest full-scale dynamometer test of a wind turbine drive train ever done in the United States.

Samsung officials wanted to learn how well their 250-foot-high wind turbines would survive 25 years of gales, gusts, rain, rust, cyclones and dust.

They turned to NREL because its dynamometer can simulate worst-case wind conditions 24 hours a day. In a few months of testing, a manufacturer can learn whether its gear boxes, bearings and cog wheels will stand up to real-world conditions.

NREL's 2.5-megawatt dynamometer is outfitted with a powerful 3,550-horsepower electric motor coupled to a three-stage epicyclic gearbox. The motor can produce speeds up to 30 revolutions per minute, simulating everything from soft breezes to backbreaking gales.

Decades of Data in Two Months of Testing

"If we tried to get this information out in the field, it would take years to acquire this kind of data," Ed Overly, master research technician and dynamometer gatekeeper at NREL's National Wind Technology Center (NWTC), said. "We run the turbine under test conditions for 24 hours a day, seven days a week at 2.1 megawatts. We can monitor how all the fluid and bearing temperatures equilibrate at their maximum points. We see how well the inverter operates under different load conditions to detect if there are any unknown faults."

"Doing this test with Samsung has given us the experience of testing a very large machine at the Dynamometer Facility, which we've never done before," Overly said.

Samsung already has a similar sized (2.5-megawatt) wind turbine running in Lubbock, Texas, that can provide electricity for 1,800 homes, said In-kyu Kim, manager of the Wind Turbine Development team at Samsung. But the company had never tested one of its turbines above 600 kilowatts.