The power exponent under different stability has no specific temperature observation instrument on the iron tower, and lacks specific atmospheric stratification data. Therefore, it can only be used as a qualitative atmospheric stratification stabilization time from sunny night to dawn, and as the atmospheric stratification instability time during the daytime noon. And after the morning sunrise and before the afternoon sunset, the atmosphere is approximately close to the neutral balance. Therefore, the relationship between the power exponent m and the atmospheric stratification can be analyzed by the daily variation of the power exponent under sunny conditions. Whether the sea breeze or the land breeze is the nighttime atmospheric stability, the power exponent m is the largest, the noon atmospheric instability is the smallest, and the morning or evening is close. The neutral balance is somewhere in between. The power index of the average wind speed is mainly based on the calculation and analysis of the wind energy parameters. Therefore, when calculating the power exponent m, only the m value under the daily average wind speed is calculated, regardless of the stability of the atmosphere and the direction of the wind. According to the calculation, the exponential error is between 0.5% and 2%, and the logarithmic error is between 10% and 15%. It can be seen that the exponential law is obviously superior to the logarithm law. It can also be seen from this that the exponential law is more suitable for Guangdong. The coastal coastal wind changes with altitude. The wind changes with the attenuation of the distance from the sea. The sea surface has less friction than the undulating land. Under the same atmospheric pressure, the sea wind speed is larger than the land wind speed. As the distance from the sea increases, the wind speed is gradually attenuated. The spatial range of wind energy storage calculations is based on the height of the tower of large wind turbines of 30 to 50 m or more. Therefore, when calculating the coastal wind energy storage in Guangdong Province, the height is 50 m. The horizontal range is the length and width of the coastal zone. The length of the coastal coastline of Guangdong Province is taken. The width is taken as 2km according to the calculation result of the attenuation of the wind with the distance from the sea.
This paper chooses direct statistical method, because the data we observe on site is collected by self-recording. This kind of observation data is suitable for direct statistical method. Its calculation formula is as follows: W=1N∑k112QNiV3i where W is the average wind energy density. Ni is the number of occurrences of a certain grade wind speed Vi, N is the total number of observed wind speeds, K is the number of wind speed classifications, and Q is the air density. The air density at each observation point in this paper uses the multi-year average air density of the adjacent weather station. According to the on-site observation data, since the wind energy density calculated above is 10m height, and the height of the wind turbine installation is 30-50m, it is necessary to convert it to the same height when calculating the wind energy storage. According to the law of wind variation with height - the index law and the wind energy density calculation formula, the wind energy density of 10 m height can be converted to a height of 20 to 50 m. As a result, the wind energy densities at the heights of 10, 20, 30, 40, and 50 m were 250, 381, 487, 579, and 663 Wm-2, respectively. The length of the coastal zone is 3369km in length and 2km in width. The coastal zone area is S=(3369×103)×(2×103)=6.738×109m2. The total storage capacity of coastal wind energy and the wind energy storage capacity of 10m height can only be 5264×104kW, but it reaches 1.396×108kW at 50m height. Therefore, appropriately increasing the installation height of the wind turbine can significantly improve the utilization rate of wind energy. Wind energy storage does not mean that all can be used for development, so it is also necessary to consider the amount of development.
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