Wind Turbine Flicker Calculator

This small applet allows users to estimate the potential flicker impacts on a power system resulting from the interconnection of wind turbine generators (WTGs). This applet estimates the number of wind turbines that can be interconnected to a system with a given system short-circuit MVA and X/R ratio before a specified flicker limit is exceeded. These calculations are based upon IEC 61400-21 "Wind turbine generator systems - Part 21: Measurement and assessment of power quality characteristics of grid connected wind turbines." Two flicker levels are calculated, one for continuous operation and the second for switching operation (startup and shutdown).

Note that to view the code used within this applet, simply Click "RPad/Unhide all code" to view the code used to generate this page.

First of all, you will want to select a wind turbine from the below list. Due to the proprietary nature of manufacturer-specific data, the turbine make and manufacturer are omitted. If you have test data for a specific turbine, and would like to use the data with this applet, simply send me an email with the data attached and I can add it to the list.

Now, you will want to input a few parameters specific to the site.

Pst Planning Level
System Impedance X/R Ratio
Average Site Wind Speed (m/s)
Maximum Short-Circuit MVA


by Jeff Smith, jsmith, Copyright 2005 EPRI, license: GNU GPL v2 or greater

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