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Five Megawatt Dynamometer Test Facility (Text Version)

Below is the text version for the Five Megawatt Dynamometer Test Facility video.

Hello, I'm Fort Felker, the Director of the Department of Energy's National Wind Technology Center. We're here today in the new 5 megawatt drive train testing facility that has been developed over the last few years. This terrific new facility has a comprehensive set of capabilities that can be used for the development of new drive train technologies to improve their performance, reduce their costs, and improve their reliability. Let's go take a look at some of their characteristics.

To really understand the capabilities of the new facility, we're going to take a close-up look at the apparatus that makes it all tick. Mark, take us up.

The power to drive the test apparatus and the test article is provided by a 6-megawatt electrical motor.  You can see that on the far right in a dark gray blue.

The high-speed output shaft from the 6-megawatt motor is used to drive our 75 to 1 gearbox, that's the light blue apparatus immediately to the left of the motor. This transforms the low-torque high speed output of the motor into the extremely high-torque low-shaft speed that's appropriate for a wind turbine drive train. The output speed varies from 12 to 24 RPM, which is a good match for the 2 to 5 megawatt system that the facility is sized for.

Next, we have what can really be thought of as the heart of this system. The non-torque loading system, the squarish blue apparatus to the left of the drive line. This allows us to load the wind turbine drive train system with the movements and shears that experiences out in the real world operation, both dynamically and statically. This is found to be a very important feature to have for test apparatus because of the adverse impacts that these types of off-axis loadings can have on the systems if not properly accounted for.

The output from the non-torque loading system is connected to the article under test. In this case, we have a 2.75 megawatt wind turbine from General Electric. The red flange adaptor allows us to match the bolt pattern that outputs the shaft and loads from the non-torque loading system onto the hub for the wind turbine drive system.

This allows us to pass the full torque and the full off-axis loads into the article under test.

The final, critically important piece of our test apparatus is the controllable grid interface that allows us to very precisely control the grid that the test article sees. Let's go take a look.

Mark, take us down.

This is our controllable grid interface, or CGI. It allows us to precisely control the grid that the test article sees. It has a continuous power rating of 7 megawatts, and importantly, a peak transient power capability of almost 30 megawatts. Let's go inside and take a look.

The controllable grid interface is a collection of high amperage power electronics contained in these cabinets, all which are computer controlled and allow us to simulate grid anomalies, such as over frequency events, overvoltage or undervoltage. Let's take a look inside one of these cabinets at the heart of the system.

Here we see the heart of the system. Three different phases of multi-level power electronics. Basically giant transistors, that allow us to precisely control the power characteristics that are supplied to the test article. The total current capability is over 30 million watts. The size of the copper bars that transmit that current back to the test article are indicative of the magnitude of the current.

You know, it looks like something out of a Frankenstein movie, and that's completely appropriate because it proves a monstrous capability.

Well that concludes our tour of our new 5 megawatt dynamometer facility. We're really excited about the capabilities it provides for developing the next generation of wind turbine technology.