Analysis, design and testing of a novel direct-drive wave energy converter system

A coupled electromechanical and hydrodynamic time-domain simulation of a direct-drive generator connected to a heaving buoy for wave energy conversion is presented. The system is based on a novel direct-drive power take-off unit referred to as snapper. The simulation is based primarily in MATLAB using its built-in ordinary differential equation solvers. These solvers act on the data derived from electromagnetic finite element analysis and from the WAMIT wave interaction simulation software. Test results of a generator prototype for comparison with the electromechanical simulation are presented. Results from wave tank tests of a full system incorporating the power take-off are also provided for comparison with the hydrodynamic model.

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