เอกสารการประชุมวิชาการและเสนอผลงานวิจัย มหาวิทยาลัยทักษิณ ครั้งที่ 19 2552 - page 245

„µ¦ž¦³»¤ª·µ„µ¦Â¨³Áœ°Ÿ¨Šµœª·‹´¥ ¤®µª·š¥µ¨´¥š´„¬·– ‡¦´ÊŠš¸É 19 ž¦³‹Îµže 2552
Abstract
The objective of this research is to analyze the statistical wind along the coast of Chana district in
Songkhla province using the Weibull distribution method. The 10 min interval wind data for 1 year period
starting from January 2008 until December 2008 at height of 20 m 30 m and 40 m a.g.l. which are the
measured data from Chana wind energy research station were analyzed according to the Weibull distribution
method with 0.5 m/s bin. Using the graphical method, the k-shape and c-scale parameters were obtained. The
average mean speed was then computed using the Gamma function. The monthly Weibull distributions of
statistical wind data along the coastal line of Chana district were created for illustration of various Weibull
parameters. The analyzed Weibull parameters were compared to the results obtained by the WAsP 9.0 analysis.
The percentage absolute error was considered. Results showed that for the wind speed at height of 20 m a.g.l.
the k-shape parameters were in the range of 1.2-2.4 the c-scale parameters were in the range of 2.1-4.5 m/s. The
calculated mean speed was in the range of 1.9-4.1 m/s. at height of 30 m a.g.l. were in the range of 1.5-2.6 and
the c-scale parameters were in the range of 2.3-5.4 m/s. The calculated mean speed was in the range of 2.0-4.8
m/s. For the mean speed at height of 40 m a.g.l. the k-shape were in the range of 1.3-2.8 and the c-scale
parameters were in the range of 3.5-5.9 m/s. The calculated mean speed was in the range of 3.0-5.9 m/s, Finally,
the percentage absolute errors were in the range of 0.8-18%, 1.7-15.2% and 0.1-16.8% at height of 20 m,30 m
and40 m a.g.l. respectively
Keywords: Wind speed, Weibull distribution, Shape parameter, Scale parameter, Mean Absolute Error
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