Windographer Screenshots
The following screen shots show the main windows and features of Windographer. Windographer's powerful analysis capabilities are easy to navigate and to use. They can all be accessed from the the tabs, toolbar icons or menus.
Main Window
Windographer's main window consists of eleven tabs, nine of which display the data set in graphical format, plus a tables tab and a reports tab. All graphs and underlying data can be exported. In addition, further tools and analysis features can be accessed from the toolbar and menus.
Summary
The Summary tab shows the vertical wind shear profile, a wind rose, and the daily and seasonal wind speed profile:
Time Series
The Time Series tab allows you to plot any of the data columns in one or two graphs. You can zoom in on any portion of the year, and use the scroll bar to move forward or backwards. You can plot the measured data or the daily, monthly, or annual averages:
Wind Rose
The Wind Rose tab allows you to create many types of wind rose plots showing wind direction frequency, the average value of a particular data column per direction sector, total energy per direction sector and even polar scatterplots. You can plot the entire data set, or select a particular year and/or month to plot only a subset. You control the number of direction sectors and the drawing style, and you can choose whether you want to see one overall wind rose, one for each month, or one for each two-hour segment of the day. The graphs update instantaneously as you make those choices.
Daily Profile
The Daily Profile tab shows the average daily profile of any data column. You can plot data from a particular year and/or month, and choose between creating a single graph or one graph for each month.
Probability Distribution Function (PDF)
The PDF tab shows the monthly or overall probability distribution function (frequency histogram) for any data column. Windographer will plot the best-fit Weibull distribution for your wind speed PDF. As on the Profile tab, you can plot data from a particular year and/or month, and choose between creating a single graph or one graph for each month.
Scatterplot
The Scatterplot tab allows you to plot one data column versus another. The example below plots the wind speed at two heights for a single month. Windographer calculates the line of best fit, which you can display on the graph if you choose.
Tables
The Tables tab allows you to see data summaries and to create many types of tabular reports. You can create monthly, annual or directional summaries or detailed profiles for any data column.
Windographer can also generate tables by bin and direction for any data columns to allow detailed analysis. All tables can be exported.
Reports
The Reports tab allows you create standardized reports from your data sets. You can print a report or save it as a PDF file. There are two reports available, a Summary report of the full data set, or a Monthly Report with detailed data for a particular month.
Windographer Analysis Tools and Capabilities
Wind Shear Analysis
The Wind Shear Analysis window looks at the wind shear (the variation of wind speed with height) in greater detail. It shows the effect of season, time of day, and wind direction on the surface roughness or the power law exponent:
Turbulence Analysis
The Turbulence Analysis window shows how the turbulence intensity varies with wind speed, wind direction, month and time of day. Analysis can be quite detailed as you filter by wind direction, year, month and/or wind speed. You can graphically compare the turbulence in your data set with standard IEC turbulence categories by plotting the IEC Categories on the graph.
Wind Turbine Output
The Wind Turbine Output window allows you to estimate the energy production of a wind turbine in the measured wind regime. In its calculations, Windographer takes into account the effects of varying air density and wind shear, and it lets you enter loss factors. Windographer will calculate detailed monthly turbine output, or compare several turbines. A large wind turbine library is included with Windographer.
Tower Shading Analysis
The Tower Shading Analysis can help to explore the effects of tower shading on a wind speed sensor. Windographer displays graphically the differences in measurements between two wind speed sensors as a function of wind direction.
Quality Control
The Quality Control window lets you detect and fix problem data segments, such as icing events or sensor malfunctions. It keeps a permanent record of the changes you make, and you can restore the original data at any time.
Virtual Anemometer
The Virtual Anemometer window allows you to synthesize wind speed data for any height above ground. This can be used to estimate the wind speed at the hub height of a selected wind turbine.
Gap Filling
Windographer can fill gaps in the data set using an advanced Markov algorithm that takes the average daily pattern into consideration. For data sets with multiple anemometers at different heights, you can select whether the algorithm uses the average wind shear or considers the time-dependent nature of the wind shear when synthesizing data:
The gap filling procedure can fill gaps of any length with statistically reasonable synthetic data. The thin dotted lines in the example below show the synthetic data:
Probability of Exceedence
Windographer can analyze the distribution of annual mean values for a particular data column, and calculates the probability that the annual mean will exceed certain values.
Extreme Wind Speed Analysis
Windographer can also perform an analysis of extreme wind speeds. Given two or more values of annual peak wind speed, it calculates the best-fit Gumbel distribution and uses that distribution to predict the 25, 50, and 100-year gusts.
Frequency Distribution
Windographer uses three different algorithms to fit the Weibull distribution to wind speed data, and plots them all on the same graph, along with the frequency histogram of the measured wind speed data.
