Wind turbine with horizontal axis, that is to say that the axis of rotation of the wind wheel is parallel to the direction of the wind
< strong>Vertical axis wind; turbine, that is, the rotation of the wind wheel The axis is perpendicular to the ground or to the direction of air flow
The vertical axis wind turbine (wind turbine verTIcalaxis VAWT) is mainly divided into drag type and elevator type.
The drag type vertical axis wind turbine mainly uses the resistance generated by the air flowing through the blades as the driving force, while the lift type uses the lift generated by the air flowing through the blades. through the blades as a driving force. . Since the resistance of the blades during rotation decreases sharply as the rotation speed increases, while the lift increases instead, the efficiency of the lift type vertical axis wind turbine is much higher than that of the lift type with drag.
IThere are several types of vertical axis wind turbines that use resistance to rotate. Among them are wind turbines made of flat plates and cups, which are pure resistance wind turbines, which have partial lift; , but it is primarily a resistance device. These devices have a large starting torque, but a low tip speed ratio, and provide low power output when the size, weight and cost of the wind turbine are certain.