US-based American Superconductor’s (AMSC) Power Systems unit entered into a partnership with Chinese wind-power giant Sinovel when it bought Austria’s Wind Tech in early 2007, which it renamed AMSC Windtec.

As the Chinese company grows into one of the world’s biggest turbine manufacturers, AMSC Power Systems’ profits have surged, with Sinovel now accounting for 60%–70% of the company’s revenue.

Sinovel uses AMSC Windtec’s design for its 1.5-megawatt