Effect of mooring mode and internal mass block layout on eccentric rotating wave energy converter model

Abstract

Reliability and energy conversion ability are the most concerned performance indexes of Wave Energy Converter Eccentric Rotating Wave Energy Converter (ERWEC) with closed shell can protect energy conversion unit away from seawater, which has shown excellent reliability. However, energy conversion ability of Eccentric Rotating Wave Energy Converter is poor and the method to improve performance of ERWEC is still not clear. The objective of this work is to improve mooring security, motion attitude stability and energy conversion ability of ERWEC. In this paper, experimental model of ERWEC was developed, and energy conversion mechanism was clarified. Experiments on various mooring modes and various internal mass block layouts were carried out. Besides, breaking coefficient, instability coefficient and energy conversion coefficient were calculated to evaluate performance of ERWEC. The result showed that the effect of mooring mode on mooring security, motion attitude stability and energy conversion ability was coupled to the effect of internal mass block layout on those three indexes. Furthermore, under determined mooring mode condition, internal mass block layout was optimized by multi-objective genetic algorithm. This paper provides basis for conceptual design of mooring mode and real-time control of mass block layout to achieve better mooring security, motion attitude stability and energy conversion ability of ERWEC.