Abstract: In the framework a project funded by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU), various power take-off technologies for rotor driven tidal turbines will be analysed in detail.
Technologies under investigation are - amongst others - direct drive systems based on permanent magnet generators, multi or single stage gearbox and medium/high speed generator, hydrodynamic gearbox and high speed generator, hydrostatic conversion and high speed generator.
The aim of the work is to compare efficiency, weight and cost as well as the maintenance requirements and other relevant specifications for the variable speed operation of vertical or horizontal axis tidal turbines. The consequences of scaling the turbine e.g. from some hundred kW/rotor to 1MW/rotor or more will be analysed. Solutions developed for wind energy and hydropower will be compared to the requirements for this new application and design recommendations will be made for the most promising technologies.