Wind gust 10 to 15 knots, the term "gusts" is used while "strong gusts" is used for departure of 15 to 25 knots, and "violent gusts" when it exceeds 25 knots. Wind gust A gust or wind gust is a brief increase in the speed of the wind, usually less than 20 seconds. It is of a more transient character than a squall, which last minutes, and is followed by a lull or slackening in the wind speed. Generally, winds are least gusty over large water surfaces and most gusty over rough land and near high buildings. The wind is measured using
Variable speed wind turbine as noise levels, this is not possible for the full range of sub-rated wind speeds. Below the rated wind speed, the following operating strategy is employed: Above the rated wind speed, the pitching mechanism is employed. This allows a good level of control over the angle of attack, thus control over the torque. The previous torque rotor-speed diagrams are all plots when the pitch angle, formula_38, is zero. A three dimensional plot can be produced which includes variations in pitch angle. Ultimately, in the 2D plot, above rated wind speed, the turbine will operate at the point marked 'x' on