與風力機設計有關之風速理論分佈與實測驗證

Verification between Theoretical Distribution and Observed Data of Wind Speed Related to Wind Turbine Design

廖育琦(Yu-Chi Liao)

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(2014年)

https://doi.org/10.6342/NTU.2014.00297

摘要

本論文旨在分析台灣西部彰濱沿海地區之風速資料，據以建構平時與颱風狀況下之風速機率模型，以做為後續風力機設計、建造與運轉之參考，並包含颱風環境下風力機處置之道。本論文分析的資料係來自交通部氣象局 2012年 10 月至2013 年 9 月所記錄的逐時風速，分別考量每小時、每天、每月、每季到每年的風速資料，尋找各自的機率密度函數，除製作直方圖外，也加入極值分佈曲線，以上風速分佈與風力機結構之可靠度息息相關。本論文也針對颱風來襲時的特殊風速進行研究，主要係依據 Pareto 分佈理論，探討颱風來襲時之風速分佈，以及風速超越一給定臨界值的發生次數。現有產業及其示範風場因經濟效益考量，所訂定的停機風速通常為 25 m/s，本論文依該數目選擇適當臨界風速，計算颱風測站觀測到最大風速與臨界風速間之正差值，繪製平均差值對超越臨界風速次數之點狀圖與趨勢線，據以獲得Pareto分佈之參數，其呈現重尾分佈。本論文建議依以上分析結果訂定停機風速，以確保風力機安全，並且預防颱風可能造成的損害。
本論文最後假設離岸風力機所受的風速為韋伯分佈，推估離岸風力機可能受到的
風速，並提供台中港設置風力機的實例作為參考。

關鍵字

可靠度工程 ； 風力發電 ； 離岸風力機 ； 風速統計 ； 極值分佈 ； Pareto 分佈

並列摘要

The present thesis analyzes wind data collected from Changhua coastal areas in western Taiwan for the purpose of constructing wind-speed probability models which are closely related to the design, construction and operation of wind turbines. The data are hourly wind speeds recorded form October 2012 to September 2013 by Center Weather Bureau, Ministry of Transportation of Taiwan. Data for the above hourly average wind speed are fitted by appropriate probability density functions based on hourly, daily, monthly, quarterly, and annually collected wind speeds, respectively. The extreme value distribution of wind speed derived from order statistics is also investigated. The above probability distributions of wind speed and extreme value of wind speed are closely related to the structural safety of wind turbines. The probability distribution of wind speed during typhoon period is also studied, primarily considering that it has a Pareto distribution. It is found that the extreme value distribution fits the collected wind data very well. It is also found that the generalized Pareto distribution is appropriate to describe the extreme wind speed during typhoon periods. The distribution s a heavy-tail one, and the analytical result is helpful for us in selecting a threshold wind speed for the safe shutdown of a wind turbine during typhoon period. In the final part of this thesis, the offshore wind speed is assumed to have a Weibull distribution. The construction of offshore wind turbines near Taichung harbor is given as an example.

並列關鍵字

reliability engineering ； wind power ； offshore wind turbine ； statistical model ； extreme value distribution ； generalized Pareto distribution

參考文獻

組廠址選擇及工程可行性研究，國科會專題研究計畫成果報告，2007。

1. H.T., Yeah, “Evaluation of the Impact of Climate Change on Wind Power and

2. T. J, Chang., et al, “Assessment of Wind Characteristics and Wind Turbine

4. J. D., Holmes “Prediction of design wind speeds,” Wind loading and

5. O. Perrin, H. Rootzen, and R. Taesler, “A discussion of statistical methods