characteristics for wind energy and wind turbines by considering vertical wind shear
来源期刊:中南大学学报(英文版)2015年第6期
论文作者:ZHENG Yu-qiao ZHAO Rong-zhen
文章页码:2393 - 2398
Key words:weibull distribution; wind power; vertical wind shear; power-law process; parameter estimation
Abstract: The probability distributions of wind speeds and the availability of wind turbines were investigated by considering the vertical wind shear. Based on the wind speed data at the standard height observed at a wind farm, the power-law process was used to simulate the wind speeds at a hub height of 60 m. The Weibull and Rayleigh distributions were chosen to express the wind speeds at two different heights. The parameters in the model were estimated via the least square (LS) method and the maximum likelihood estimation (MLE) method, respectively. An adjusted MLE approach was also presented for parameter estimation. The main indices of wind energy characteristics were calculated based on observational wind speed data. A case study based on the data of Hexi area, Gansu Province of China was given. The results show that MLE method generally outperforms LS method for parameter estimation, and Weibull distribution is more appropriate to describe the wind speed at the hub height.
ZHENG Yu-qiao(郑玉巧), ZHAO Rong-zhen(赵荣珍)
(Key Laboratory of Digital Manufacturing Technology and Application of Ministry of Education
(Lanzhou University of Technology), Lanzhou 730050, China)
Abstract:The probability distributions of wind speeds and the availability of wind turbines were investigated by considering the vertical wind shear. Based on the wind speed data at the standard height observed at a wind farm, the power-law process was used to simulate the wind speeds at a hub height of 60 m. The Weibull and Rayleigh distributions were chosen to express the wind speeds at two different heights. The parameters in the model were estimated via the least square (LS) method and the maximum likelihood estimation (MLE) method, respectively. An adjusted MLE approach was also presented for parameter estimation. The main indices of wind energy characteristics were calculated based on observational wind speed data. A case study based on the data of Hexi area, Gansu Province of China was given. The results show that MLE method generally outperforms LS method for parameter estimation, and Weibull distribution is more appropriate to describe the wind speed at the hub height.
Key words:weibull distribution; wind power; vertical wind shear; power-law process; parameter estimation