On the design and performance of a power electronics converter for the DeepWind project

DeepWind is a vertical axis wind turbine (VAWT) concept, with the turbine rotor mounted on a floating spar buoy with the generator at the bottom up to 300 m below the sea. To control the starting, variable speed and overspeed limitation operation of the VAWT, the only method available is to control the torque and speed of the generator. A four quadrant, three level, neutral point clamped inverter configuration is proposed and the design of this discussed. Various operational features are tested on a small scale laboratory version. Sample test results are given. The challenges of the DeepWind marine application are presented and discussed and some solutions are proposed.