UL 4143:2018 free download

UL 4143:2018 free download Wind Turbine Generator Life Time Extension (L TE)
6 Requirements for life time extension
6.1 General
6.1.1 In order to extend the lifetime of a wind turbine based on RPN determination criteria, the windturbine(s) in a wind farm shall comply with the requirements mentioned in Sections 6.2-6.7.
6.2 Step 1: Requirements for external conditions
6.2.1 Operational historical data of external conditions relevant to the structural loading of the windturbine(s) in the wind farm shall be used.
6.2.2 To assist in determining site external conditions SCADA data，met mast data,and/or publicdatabases may be used.The respective source shall be named.
6.2.3 To cover the seasonal variations in wind characteristics, the measurement period shall cover atleast 12 months. The measurement device set-up except for the met mast location shall comply with Windturbines – Part 12-1: Power performance measurements of electricity producing wind turbines,IlEC61400-12-1.The on-site measurement location shall be chosen to achieve representative measurementsfor the wind turbine(s) under assessment.
6.2.4 The analysis of the measured data shall comply with Wind turbines – Part 12-1: Powerperformance measurements of electricity producing wind turbines, IEC 61400-12-1 or other equivalentstandard like MEASNET, as applicable.
6.2.5 The following information shall comply with the requirements outlined in IEC 61400 series.
6.2.6.1 Site topography
a)Details of the sitel wind farm;
b)Details of the site lay-out and change in layout;
c) Wind farm layout coordinates
d)Neighboring wind farms in a radius of 20 rotor diameters (past and future)
e) Roughness map of the site in an area of 15 km around the site
f)Assessment of complexity; and
g)Assessment of obstacles.6.2.6.2 Measurement equipment
a)Details of met mast;
b) Details of measurement equipment; andc) Description of data logging.
6.2.6.3 Other information
a)Filtering and other data verification analysis;
b)Calibration details;
c) Details of the extrapolation models including the model validation;
d)Details of the wind modeling and uncertainties;
e) Historical changes to the site/forestation (tree growth or logging); and
f) Applicability of the measurements to past and future periods. In case of any possiblechanges to the site, these shall be considered in the extrapolation of data to future periods.
6.2.6.4 Wind speed and wind direction
a) General
1) The wind speed bin shall be 2 m/s bins or less;
2)Wind direction sector shall be 30 degrees or less; and3) The wind speed shall be given as a 10 minute average.
b) Methods for long term assessment
6.2.6.5 Wind speed distribution
1) The probability distribution function shall comply with Wind turbines – Part 1 Design
requirements,lEC61400-1.
6.2.6.6 Turbulence
a) 10 minute average turbulence intensity values for each wind speed bin and each wind direction sector shall be used;
b) The wake induced turbulence intensity shall be accounted in the assessment.The methodology shall be compliant with Wind turbines – Part 1: Design requirements,IEC 61400-1;and
c) In case of a complex terrain, the site complexity shall be accounted in the turbulenceintensity calculation.