A novel single-body system for direct-drive wave energy converter

Ocean wave energy has played a key role of the renewable energy. This study presents a novel single-buoy wave energy converter (WEC) with directly driven power take-off (PTO) system to overcome some difficulties that the PTO system in the conventional single-body direct-drive WEC (DD-WEC) is fully submerged under water and far away from the water surface. A rectangular buoy, a direct-drive PTO system with Halbach permanent magnet linear generator (HPMLG), and slide rails form the chief institutions of the WEC. The translator of the HPMLG is installed on the lateral surface of buoy, and the stator is mounted on the seacoast or the boats and ships. While wave drives the floating buoy to move, a relative movement between the translator and the stator of the HPMLG is caused. Then, the relative movement generates electricity. To explore theoretically its feasibility, the dynamics of the wave and the floating buoy is analyzed in detail. Thus, the structural parameters are analyzed and determined, and load performance is described. Furthermore, the finite element method (FEM) is used to conduct the performance evaluation of the HPMLG and traditional permanent magnet linear generator (TPMLG). The generated power of the HPMLG is 19% higher than the TPMLG under the same conditions. Lastly, Experiments of a fabricated prototype are conducted in the wave tank. Experimental results show that the prototype in this paper decreases these existing problems and is suitable for wave energy generation.

Automated summary

Ocean wave energy plays a vital role in renewable energy, and a novel single-buoy wave energy converter with a directly driven power take-off system has been proposed in this study to address challenges faced by conventional direct-drive WEC systems. The HPMLG installed on the buoy generates electricity through relative movement with the stator attached to the shore or vessels. Performance evaluation using FEM shows that the HPMLG outperforms traditional linear generators by 19% in power generation. Experiments conducted in a wave tank demonstrate the feasibility of the prototype in improving existing issues and its suitability for wave energy generation.