Wind gust World Meteorological Organization. Any significant variation at this mean wind during the ten minutes preceding the observation are noted as gusts in messages such as METAR. It is generally reported in METAR when the peak wind speed reaches at least 16 knots and the variation in wind speed between the peaks and average wind is at least 9 to 10 knots. In marine meteorology, the top speed of a burst is expressed in meters per second (m/s) or in knots, while the Beaufort scale is used for reporting the mean speed. When the maximum speed exceeds the average speed by
Variable speed wind turbine example of a permanent magnet generator is the Siemens SWT-2.3-113. A disadvantage of a permanent magnet generator is the cost of materials that need to be included. Consider a variable speed wind turbine with a permanent magnet synchronous generator. The generator produces AC electricity. The frequency of the AC voltage generated by the wind turbine is a function of the speed of the rotor within the generator: formula_39 where formula_40 is the rotor speed, formula_10 is the number of poles in the generator, and formula_42 is the frequency of the output Voltage. That is, as the wind speed varies, the