Horizontal axis power generation can also be used when the wind speed is greater than 30 meters/second. It is only necessary to shorten the blades and reduce the swept area. It is enough to ensure that the wind turbine load can be within the rated bearing range at 30 meters/second. However, this adjustment will It affects the cut-in wind speed, and the low wind speed section will be affected. Turbine generators with high power have not yet been seen in China. If it is a special occasion in a wind tunnel, if a tower is not needed, you can actually use a turbine fan plus an AFE unit to generate electricity. .
When the wind speed is too high, after the wind turbine is shut down, is it yawed so that the impeller rotation plane is parallel to the wind speed?
The Darrieus wind turbine is the earliest lift-type vertical axis wind turbine, referred to as D impeller. It was invented by a French engineer named G.J.M. Darrieus and was patented in 1931, but it was not taken seriously until the late 1960s. After extensive research by the National Aerodynamics Laboratory of Canada and the Sandia Laboratory of the United States, the Darrieux wind turbine has practical value. Compared with all vertical axis wind turbines, it has the highest wind energy utilization coefficient. At present, all lift-type vertical axis wind turbines can be classified as Darieux-type wind turbines.
Characteristics of Darieu wind turbine
The Darieu wind turbine is a newly developed vertical axis wind turbine named after the French inventor Darieu. The picture shows the ordinary Φ-shaped Darieu wind turbine and the special Δ-shaped Darieu wind turbine. Its leaves are mostly 2-3. The wind turbine rotates independently of the wind direction and is a lift type. Its installation is simple and its cost is relatively cheap, but its starting performance is poor, so some people use this wind turbine in combination with a Sabnius wind turbine.
The feathering process does have nothing to do with yaw. As for the case where feathering alone cannot protect the wind turbine due to excessive wind speed, yaw does reduce the total windward area of the blades. As for whether it is specifically adopted There is no mention in the book about fans that are protected in this way. Someone should have done it, but it is conceivable that the effect is not very good.
Before cutting out, the fan is not only subject to static load, but also dynamic load when the impeller rotates. When stopped, there is theoretically no dynamic load, so it should be The load is greater when rotating. However, for wind speeds of 40-50m, this is not necessarily the case and must be determined through specific calculations, so various parameters of the fan must be given.