The converters in the video have a nominal capacity of 450 Kilowatt. For an experimental plant at this development stage, this is huge. It took wind power plants over three decades of high-tech development to become larger.

Because they needed to wait until semiconductor technology could support high-power frequency converters. Note how large wind turbines arrived at virtually the same time as VVVF drives on trains, and ships, and everything else. Unlike hydro, wind turbines can’t efficiently generate at constant speed in widely varying conditions.