When the wind speed of the wind turbine changes, or when the wind speed is lower than the rated wind speed, its output power should be lower than the rated output power. As long as the wind speed changes, it is impossible to guarantee that the power output remains unchanged no matter what you do. Just like a faucet, if the valve is opened more or less at the same time, will the flow rate be the same? Absolutely not!
How do you understand the phrase “a 3 MW wind turbine”?
Wind speed. Wind energy forecasting typically requires the use of historical data and weather data for modeling. Among them, the first area to be predicted is wind speed, because wind speed is one of the main factors affecting wind power generation. Once the wind speed is predicted, the potential power output of the wind energy can be calculated by entering the valeur of wind speed in a predefined mathematical model.
How powerful is a large wind turbine?
That is, the rated power is 3 MW and it can produce 3,000 kWh of electricity per hour. Generally, to achieve the rated power, a rated wind speed (approximately 15 meters/second) is required.
The fan works between the input wind speed and the cut-off wind speed, which is about 3.5m/s ~ 25m/s: it cannot rotate when the wind is weak and it cannot work. if the wind is too strong and dangerous (so it must be stopped when a typhoon arrives).
The largest is 5 MW, one in Denmark and one in China. Generally, 2 MW, 1.5 MW or less 0.8 MW are used in China.
Formula for calculating electrical power: P=W/t =UI.
In a purely resistive circuit, according to Ohm's law U=IR and substituted by P=UI, we can also obtain: P=I2R=(U2)/R.
In dynamics: Power calculation formula: P=W/t (average power); P=Fvcosα (instantaneous power).
Detailed information
When the wind turbine produces electricity, it must ensure that the output frequency is constant. This is very necessary for both grid-connected wind power generation and wind-solar hybrid power generation. ?
To ensure that the frequency of wind power is constant, one solution is to ensure a constant speed of the generator, that is, a constant speed and constant frequency operating mode , because the generator is driven by the generator. wind turbine through the transmission device, this method undoubtedly requires a constant speed of the wind turbine, which will affect the wind energy conversion efficiency.
Another way is to change the speed of the generator according to the wind speed andensuring that the frequency of the output electrical energy is constant by other means, i.e. constant frequency and variable speed operation. The wind energy utilization coefficient of the wind turbine is related to the blade tip speed ratio (the ratio of the linear speed of the turbine tip to the wind speed). There is a certain blade tip speed ratio that causes Cp to reach the maximum value.
Baidu-Wind Encyclopedia