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 length of the blade, formula_4 is the velocity of the wind, and formula_5 is the power coefficient for the wind turbine. The power coefficient is a representation of how much of the available power in the wind is captured by the wind turbine. The torque, formula_15, on the blades is given by the ratio of the power extracted to the rotor speed, formula_2: formula_17 The rotor speed can be related to the wind speed, formula_4, through the tip-speed ratio, formula_6: formula_1 Thus we can get the following expressions for torque and power: formula_21 and formula_22 From the above equation, we