Research on conversion efficiency assessment method for wave energy converters based on field tests

The conversion efficiency of wave energy converters (WECs) is important in measuring their power performance. This study focuses on the conversion efficiency assessment method for WECs, and derives a rapid calculation method for wave energy period data, proposes a calculation method for wave energy capture capability, and investigates the analysis method for WEC conversion efficiency data. The maximum conversion efficiency obtained via the proposed conversion efficiency calculation method is 35.8%; this represents an increase of ≈18.2% compared with the existing method. The robust coefficients of variation of the conversion efficiency datasets obtained by the two calculation methods are 0.41 and 0.43, respectively. The peak distribution frequency of the conversion efficiency dataset from the proposed method in this study has shifted rightward to the conversion efficiency range of 16–20%, with a maximum distribution frequency of ≈14.6%. The maximum average conversion efficiency within the grid obtained by the proposed method is 24.22%. The rate of increase in average conversion efficiency within the significant wave height range of ≈ 1.1–1.3 m is relatively lower than that in other significant wave height ranges; when the wave energy period is ≈5 s, the average conversion efficiency reaches the maximum value.