复杂下垫面风电场风速数值模拟及误差特征  

Numerical simulation and error characteristics for wind speed on a wind farm over a complex underlying surface

作　　者：祖繁[1] 樊曙先[1] 王咏薇[2] 吴息[2] 

机构地区：[1]南京信息工程大学大气物理学院,江苏南京210044 [2]南京信息工程大学大气环境中心,江苏南京210044

出　　处：《大气科学学报》2016年第5期672-682,共11页Transactions of Atmospheric Sciences

基　　金：江苏省科技支撑计划(BE2010200);江苏省高校优势学科建设工程资助项目(PAPD)

摘　　要：利用WRF模式分别对沿海及山地条件下风电场风速进行高分辨数值模拟,并对其误差特征进行分析,结果表明:1)WRF模式对复杂地形条件下的风速模拟性能良好,模拟值较好地体现天气尺度的周期变化;2)沿海及山地条件下模拟与观测的误差特征各不相同。模式静态数据未能显现沿海的小岛,并且低估了山地测风塔所在的海拔,导致沿海平均模拟风速偏大,山地平均模拟风速偏小;3)分析不同风向的归一化均方根误差,沿海陆风情况下,下垫面相对复杂,误差明显增大;沿海海风情况下,下垫面均一,误差明显减小;4)仅作单个风电场周边数百平方千米的模拟,采用一台12核的服务器进行WRF模式的并行计算可满足48 h短期预测的时效性。仅仅提高模拟的网格分辨率,并不一定能提升模拟的准确性。Accurate wind speed forecasts ensure the timely dispatch of power, thereby improving the economic effec- tiveness of wind power.The traditional methods of wind speed prediction focus on statistical models ,but these are unable to satisfy requirements in terms of precision and time. Numerical models have become more prevalent in wind speed forecasting in recent years. Accordingly, in order to investigate simulation accuracy, error characteristics and time effectiveness for wind speed simulation of a numerical model over a complex underlying surface,one-month long wind speeds at the heights of 10 m, 30 m, 50 m and 70 m on a wind farm in Liuao （coastal area） and Jiucaiping （mountain area） are respectively simulated using the WRF model.The main results and discussion points are as follows： （1） The comparison of simulated and observed wind speeds at different heights indicates that the WRF model performs well in simulating the wind speed over a complex underlying surface, the simulated wind speed trends are in good agreement with the observations in both coastal and mountain areas, and the synoptic-scale var- iations are also well reflected in the simulation.However, the fluctuation caused by the local circulation and turbu- lence is hard to capture in the wind speed simulation.Besides, statistical assessments using correlation coefficients,relative error,root-mean-square error （RMSE） and index of agreement show that the accuracy of wind speed sim- ulation does not enhance with increased height in coastal areas, but improves significantly in mountain areas. （2） The error characteristics between simulations and observations are different in coastal and mountain areas.Compared with the real landforms,the small island in coastal areas does not appear in the model＇s static ter- restrial data.As a result, the frictional effect of the underlying island is neglected in the simulation, and the average simulated wind speeds are overestimated in coastal areas. Nevertheless, the elevation of the wind to

关 键 词：复杂下垫面 WRF模式 风速 数值模拟 误差特征 网格分辨率 

分 类 号：P456.7[天文地球—大气科学及气象学] TM614[电气工程—电力系统及自动化]