平原地区风切变指数的计算方法

Study on Calculation Method of Wind Shear Index in Plain Area

风切变指数是风的典型特征之一,是评估风能资源的一个重要参数。根据风切变指数的影响因素,对平原地区风切变指数的变化规律进行研究,分析了8种不同计算风切变指数的方法,并对由该8种方法推算得到的风速和发电量与实际情况进行对比分析。结果表明:按月、小时或者逐月按小时计算的风切变指数较为可靠,其推算的其他高度风速时间序列较为准确。该研究有利于更准确地推算风机轮毂高度处的风速,进而更准确地估算风电场的发电量。

The wind shear index is one of the typical wind characteristics and an important parameter for assessing wind energy resources.According to the influencing factors of wind shear index,the variation law of wind shear index in plain area is studied. Eight different methods for calculating wind shear index are analyzed. The wind speed and power generation calculated by the eight methods are compared with the actual situation. The analyzed results show that the wind shear index calculated by month,hour or month by month is more reliable,and the wind speed time series at other altitudes calculated are more accurate. This study is favorable for accurate calculation of the wind speed at the hub height of the wind turbine and accurate estimate of the power generation of the wind farm.