Wind field measurement over complex landforms based on Multi-rotor Unmanned Aircraft

The purpose of this study is to explore the method of measuring planar wind field over different landforms based on Multi-rotor Unmanned Aircraft (MUA) equipped with a wind speed and direction measurement device. In this study, a wind tower of a test base in Yanqing, Beijing is used as a reference. Firstly, the accuracy of MUA wind measurement is studied. Then, the wind speed and direction measured by MUA at different measuring points and the wind tower in the same period are taken for orthogonal decomposition to obtain the ratio of wind speed and turbulence between MUA and the wind tower. Through the data of the wind tower and the ratio, the wind speed and direction of different positions are deduced, and the wind field over the complex landform is obtained. The results show that the error of MUA average wind speed and average wind direction after correction is smaller. The turbulence measured by MUA is larger than that measured by the wind tower, and the turbulence measured by MUA can be reduced partly by the moving average method. The wind field conditions are greatly affected by the landforms, and the wind field over complex landforms fluctuate more frequently. The study verifies the feasibility of using MUA equipped with an anemometer to measure the planar wind field over different landforms, which can provide reference ideas and methods for wind field measurement in a local area and micrositing of wind farms.