Simulation and analysis of wind turbine radar echo based on 3-D scattering point model

Abstract

Wind turbine (WT) arrays in wind farms can cause serious interference on nearby radar stations. Thisinterference could be filtered out if wind turbine radar echo (WTRE) can be obtained accurately. Considering thesingleness of in-field experiments, numerical simulation became the majority among such works, but few of them reachednecessary accuracy. Therefore, we propose a solution method of WTRE based on three-dimensional (3-D) scatteringpoint model. Firstly, we use the nonuniform rational B-spline to build the 3-D model of WT. Secondly, based on themethod of moments (MoM), the Rao-Wilton-Gisson (RWG) basis function is adopted to discretize the integral areaof WTRE into triangular elements, which ensures the continuity of induced current on the surface of WT. Taking thecenters of triangular elements as scattering point source, we obtain the 3-D point scattering model of WT, which isthen used to derive the echo equation of WT and eventually time-frequency domain waveform of WTRE. The resultpresents high accuracy comparing with the traditional method and scaled model experiments in an anechoic chamber.Further analysis indicates that the proposed method can be used to estimate important parameters of an operating WTaccurately.