透過量測所得風速資料之統計分析預測風場之最大風速分布

Prediction of Maximum Wind-Speed Distribution in a Wind Farm Through Statistical Analysis of Measured Wind-Speed Data

張靜觀(Ching Kuan Chang)

指導教授 ： 吳文方

國立臺灣大學/工學院/機械工程學研究所/碩士(2022年)

https://doi.org/10.6342/NTU202203522

摘要

因應綠能需求且台灣海峽是世界前20名良好風場之一，近年來台灣離岸風力發電產業發展相當蓬勃。離岸風力發電機運轉壽命可達20年，於機組設計時，即需考量該期間內可能受到包含風力、波浪衝擊、海洋生物棲息地、潮濕腐蝕等外在影響因子。本研究以苗栗竹南外海離岸風速塔兩年期間所觀測到的風速資料作為示範案例，以統計方法整理並討論風速與風向隨時間與季節等因素變化趨勢，並依Gumbel所提出的極值統計理論(Statistical Theory of Extreme Values)，藉由兩年間所整理出來的風速資料，預測該風場風機壽命週期內可能發生的最大風速，以利於風機設計；而由於風速的不確定性，該最大風速需以機率密度或分布函數呈現。經分析探討，本研究發現所探討風場的風向隨季節有明顯變化趨勢，風速變化趨勢則較為緩和；本研究也成功示範我們可依風場有限期間內所觀測到的風速資料，預測該風場未來幾年會遇到的最大風速，並以機率密度函數呈現。

關鍵字

離岸風電 ； 風速 ； 機率與統計 ； 極值統計理論 ； 最大風速

並列摘要

Owing to the needs for green energy, and also considering that Taiwan Strait is one of the top 20 wind farms in the world, Taiwan’s offshore wind power industry has developed quite vigorously in recent years. The operating life of offshore wind turbines can reach 20 years. When designing the unit, it is necessary to consider external factors such as wind speed, tidal wave, marine habitat, humidity and corrosion during this period. In this study, the wind speed data obtained from an offshore observation tower in outer sea of Zhunan, and Miaoli during a two-year period is used as a demonstration case to sort out and discuss the variation trends of wind speed and wind direction along with time and seasons using statistical methods. The maximum wind speed that may occur during the operating life of the wind turbine can be predicted based on the above result and Gumbel’s statistical theory of extreme values. Owing to its uncertainty, the maximum wind speed has to be presented as a probability density. After analysis and discussion, this study shows that, with regard to the demonstrated wind farm, the wind direction has an obvious changing trend with seasons, while the wind speed changes only moderately. It also demonstrated successfully that the maximum wind speed of the wind farm in the next few years can be predicted by the observed wind speed data during a limited period of time, and it is presented as a probability density function.

並列關鍵字

offshore wind power ； wind speed ； probability and statistics ； statistical theory of extreme values ； maximum wind speed

參考文獻

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