Equivalent Modeling of Direct-drive Wave Array in Frequency Domain

The correct electric power fluctuation process of a wave array is essential for the analysis and operation of the power grid integrated with wave power. A frequency-domain equivalent modeling method is proposed to convert the wave fluctuations into the electric power fluctuations. In the proposed equivalent modeling method, a discrete transfer function for representing the wave energy conversion process, and the wake effect as well as the time delay of wave propagation in a wave array, can be obtained. The only input signal of the proposed equivalent model is the incoming wave elevation measured at the first wave energy converter (WEC) of the wave array, which is called the “original incoming wave elevation”(OIWE), and the only output signal is the total power of the wave array. The results of the case study show the effectiveness of this method.