Research on pitch control strategy and aerodynamic performance of vertical axis wind turbine,垂直轴风力机变桨控制策略及气动性能影响研究

The attack angle of the vertical axis wind turbine changes periodically during the operation. The blades are often in a dynamic stall state at low tip speed ratios, which greatly reduces their aerodynamic performance. Adjusting the angle of attack of the blades to control flow separation can improve its operating performance effectively. This paper takes the H-type Darrieus vertical axis wind turbine as the research object. Based on the rule that the variation of the angle of attack with the phase angle at different tip speed ratios, a pitch angle control strategy is proposed. That is when the angle of attack is larger, the amplitude of the change is larger, and when it is smaller, the amplitude of change is smaller, and then the influence of its control method on aerodynamic performance is verified through numerical calculation, the variation of vortex field of wind turbine is analyzed under different rotation angles, and the reason of aerodynamic load variation is also discussed. The results show that this pitch angle control strategy can significantly improve the power coefficient, and the lifting effect is more significant when the tip speed ratio is lower, at a TSR of 1.25, the power coefficient increases by 146%.