Wind energy intensity is usually expressed in terms of wind energy levels.
The level of wind force can be estimated from how objects on the ground or sea are blown by the wind. The current internationally accepted estimate of wind energy is based on the Beaufort wind scale. Beaufort was a British admiral who pioneered the wind classification standard in 1805. At first it was only used at sea, then also on land. It has been revised several times and has become the current wind level today. The empirical relationship between the actual wind speed and the Beaufort wind level is:
V= 0.836 * (B ^ (3/2))
B is the level of the Beaufort wind, V is the wind speed. (unit: m/s)
Generally speaking, the starting wind speed of the wind turbine is 2.5 m/s. When you feel the wind on your face and the leaves tremble, itbegins to generate. Electricity When the wind speed reaches 28~34 meters/second, the fan will automatically detect and stop working to reduce damage to the receiver itself.
Wind energy
Wind energy: Kinetic energy generated by the flow of large quantities of air over the Earth's surface. Due to different temperature changes and different water vapor content in the air after being irradiated by the sun, the air pressure in different places on the ground is different. In the horizontal direction, high pressure air flows to low pressure areas. which is the formation of the wind. Wind energy resources are determined by wind energy density and the annual number of accumulated hours of available wind energy. Wind energy density is the wind power available per unit wind surface and is directly proportional to the cube of wind speed.sse of wind and air density.
Mechanical anemometers are generally called cup anemometers. There are hemispherical cups and conical cups. For low wind speeds, hemispherical anemometers are better. For high wind speeds, cone anemometers are better. Both have a vertical axis relative to the horizontal plane, and there are also those that have a horizontal axis, such as small wind-powered tankers. There are not many users of wind energy, and it is suitable for situations where the environment is relatively harsh, such as corrosion, low temperature, etc. The accuracy is generally around 0.5 m/s. If the starting torque is large and the wind is too weak to measure it, the measuring range is generally 3-50-70 m/s. It can only measure wind speed in one direction, usually the horizontal direction. The givenTesting has a lot to do with the quality of the installation. If the installation is not level, the master data will be completely useless and can of course be corrected.
The ultrasonic anemometer, with an accuracy of 0.1 m/s, poses no problem. It is estimated that it can be used between 0 and 100 m/s, and 3 dimensions can be measured simultaneously. Sampling speed is also not a problem. The price is not cheap and can be used for a long time.
Today, half of the wind turbine cabin is equipped with an ultrasonic hemispherical cup and a wind direction indicator.
There are also laser and ultrasonic devices for on-site measurement. The laser anemometer can be placed directly on the ground to measure data at an altitude of 0-200m at a time, and there is no problem with the three-dimensional flow field. The valuable equipment was removed immediatelyafter half of the tests. No one dared to use it in the wild. . .