Research on Dynamic Stall of 3D Wind Turbine under Wind Speed Fluctuation

In the effect of periodically varying wind speeds, a wind turbine in an external field environment often works under stall conditions. This paper explores the factors that average wind speed, wind speed amplitude, and oscillation frequency resulted in the changes in blade torque by dynamic stall. According to the blade surface flow field during the dynamic change of wind speed, the law of surface pressure change of the blade in the period of periodic stall is analyzed, and the power changes of the wind turbine blade in the stages of no stall, light stall, and deep stall are studied. As a result, as the oscillation frequency increases, the amount of torque change also increases, and the maximum torque also increases. When the average wind speed increases, the torque experienced by the blades decreases stepwise. As the wind speed amplitude increases, the area of the closed-loop curve where the torque varies with the wind speed continues to expand. Accurately understanding the impact of dynamic stalls and stall delays on wind turbines can further improve the efficiency of wind turbines.