Adjustable speed drive with a single 100-MW synchronous motor

The aging fan drive system of the NTF wind tunnel at NASA’s Langley Research Center in Virginia, USA, was recently replaced by a new adjustable speed drive (ASD) from ABB. Its single 100-MW (135,000-HP) synchronous motor makes the NTF ASD the world’s largest adjustable speed drive system. HVDC and traditional ASD technology, as well as large rotating machinery design and manufacturing techniques, contributed to the new drive.