Electromagnetic Scattering Characteristics Analysis And Suppression Of Wind Farms Clutters For Weather Radar

The cumulative installed capacity of wind power has grown rapidly around the world.At the same time,wind power technology has become increasingly mature and the wind power industry has also developed rapidly.The impact of wind farms on nearby meteorological radar stations is increasing year by year.Because the electromagnetic scattering characteristics of wind turbines are more complex,their radar echoes are very similar to those of meteorological targets.The interference will be caused to meteorological observation equipment nearby,leading to the false detection and misidentification of meteorological targets.The study of the electromagnetic scattering characteristics for wind farms in the frequency band of meteorological radars can provide the theoretical basis for the quantitative impact analysis of wind farms on meteorological radars.For the wind farms clutter that will cause a significant impact on nearby meteorological radars,the corresponding clutter suppression techniques can be used to effectively improve the accuracy of the target parameter estimation for meteorological radar.Firstly,based on the analytical model of the Radar Cross Section(RCS)for the wind turbine whose mast is mental,considering the influence of the material of the wind turbine blade is considered and,PO method is used to analyze and calculate the electromagnetic scattering characteristics.The analytical model of cylindrical blades is built based on the numerical fitting;Secondly,considering the influence of the blade airfoil on its RCS,the UG software is used to establish the real blade model of the wind turbine.The proportion of the electromagnetic scattering characteristics of the wind turbine blade to its overall RCS is calculated under different irradiation conditions and the application range of the analytical model for the blade is selected;The idea of the equivalent area difference in the scattering area is introduced to construct an analytical model that simplifies the difference between RCS of a cylindrical blade and that of its corresponding real blade,and the analytical model of the real blade is then established to realize the RCS rapid calculation of a wind turbine blade;Finally,for the wind farm clutter by which the meteorological radars will obviously be effected,the problem of suppressing wind farm clutter by using Level-II data of meteorological radars is analyzed,and the clutter suppression algorithm based on least square surface fitting is proposed.At the same time,the performance of the algorithm is qualitatively and quantitatively analyzed by using the second moment data(Level-II data)under the different volume scanning modes of the weather radar.The corresponding conclusions are finally given.