Methodology for Performance Assessment of a Two-Body Heave Wave Energy Converter

Abstract

A wave energy farm composed by several two-body heaving wave energy converters is being developed by IH Cantabria. This study presents a methodology to obtain the power performance of an isolated two-body heaving wave energy converter, previously presented and analyzed by [1]. The methodology relies on a numerical model which represents the motion of the two bodies in the time domain. This time domain model has been built substituting the entire Cummins equation system with a state-space system, thereby avoiding the convolution integral of the radiation force term with a state-space subsystem, previously used in [2] and [3]. The performance of the device along its life cycle has been estimated based on a proposed new methodology. The new method is proposed in order to obtain the long term power production of a device with the same computational effort than the classical method based on the power matrix. The proposed method is able to estimate long term power production time series. This long time series is obtained using the MaxDiss selection technique from [4] in order to compute only the power of the most representative sea states and the Radial Basis Function interpolation technique (RBF) to obtain the complete power series.