The understanding of wind turbine wake interactions in large wind farms contributes to control power losses and turbulence increases, which is crucial to optimize the design of a wind farm. The wake effect in complexterrain wind farms is much more complicated, and the related problems are still not investigated in depth. This study tries to fill in this research gap from the experimental aspect. This paper based on the wind field measurement in a typical complex-terrain wind farm in north China. The wind turbines are built in mountainous positions and the maximum height difference between wind turbines is 171.3m. A vertical-wind-mast-type lidar and a threedimensional-scanning-wind lidar were used to measure wind turbine wakes. The multiple wake effect downstream of four aligned wind turbines are investigated. The numerical experimental data and results are demonstrated in this paper. Huge experimental difficulties exist in deciding proper lidar scan strategies and adopting effective integration of measured data from various remote sensing platforms. This study also summarizes the difficulties and gives out the experience from the measurements, which is a guidance for the future measurements in the complex-terrain wind farms.
Keywords wind field experiments, complex-terrain, wake effect, a row of wind turbines