Abstract: In order to improve the dynamic stall characteristics of airfoil and wind rotation field structure, the stationary suction device was applied to the vertical axis wind turbine. Based on the CFD method, the flow control mechanism of steady inspirations and its influence on the aerodynamic characteristics of wind turbines were studied, and the wind energy utilization rate, blade pressure coefficient, torque coefficient and flow field distribution of the whole machine under the effect of original and steady inspirations were compared and analyzed. The results show that the low-speed fluid in the boundary layer can be removed by steady inhalation, which greatly increases the pressure difference on the leading edge surface of the airfoil and delays the occurrence of dynamic stall. When the tip speed ratio was 2.51, the wind energy utilization coefficient of the wind turbine increased by 34.69%. The larger the inspiratory amplitude is, the closer the opening position is to the leading edge, the more significant the aerodynamic performance improvement of the wind turbine is. Steady suction is suitable for flow control of the vertical axis wind turbines.