Reduction for the Overspeed of Cup Anemometer

Based on an equation of the dynamic response of cup anemometer and the contrast observations between cup anemometer and sonic anemometer, It is shown that u-error caused by the overspeed of cup anemometer is about 1% and data processing error (DP-error) associated with cup anemometer is the most important one because of distinct calculated methods (vector mean and scalar mean). After the reduction for DP-error, the rational wind speed values could be obtained.