In the test, NREL blasted 12.6 million inch pounds of torque at Samsung's 185,000-pound wind turbine drive train.

NREL says it is the largest full-scale dynamometer test of a wind turbine drive train ever done in the United States.

Samsung officials wanted to test how its 250 ft tall wind turbines would survive 25 years of gales, gusts, rain, rust, cyclones and dust.

NREL's dynamometer is fitted with a 3550 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.

"If we tried to get this information out in the field, it would take years to acquire this kind of data," says Ed Overly, Master Research Technician and Dynamometer Gatekeeper at NREL's National Wind Technology Center (NWTC).

"We run the turbine under test conditions for 24 hours a day, 7 days a week at 2.1 MW. 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.”

Using a virtual wind-speed profile the computer model calculates what the main shaft torque should be and sends the torque commands to the dynamometer.

NREL is currently designing a 5 MW dynamometer that will be capable of testing most of the large turbines expected to roll off humungous assembly lines in the next decade.