Tidal in-stream generation with improved PCC voltage profile

While a variable speed, variable power turbine generator system is essential for maximum power extraction of the available power in a tidal stream, injection of a highly fluctuating power to the grid can result in degradation of the voltage quality. This investigation begins with an examination of the effect of injecting such variable powers to a non-stiff grid. A solution design based on a composite voltage source converter with separate P and Q controls is proposed. Finally an example system is designed and simulated using tidal shape data, to verify the feasibility of the proposed system.