165results about How to "Reduce fatigue load" patented technology

A wind turbine is presented where the operation lifetime of the main bearing is extended by relieving the main bearing by reducing the mean bending moment on the bearing by means of individual pitch control of the blades of the rotor so as to create an aerodynamic mean tilt moment on the rotor by means of aerodynamic forces on the blades, the tilt moment at least partly counteracting the bending moment caused by the overhang load forces on the main bearing from the gravitational pull on the rotor mass.

To provide a wind turbine generator, a wind turbine generator system, and a power-generation control method of a wind turbine generator that are capable of improving the power-generation capability and reducing the fatigue load on the windmill. A data accumulation unit 25 sequentially accumulates data sets of a generated output power P during operation of the wind turbine generator, an incoming wind speed Ws estimated on the basis of a wind speed measured at the anemometer, and a wind direction deviation, which is the difference between a wind direction θw measured at the anemoscope and the orientation of the nacelle; statistical analysis of the data accumulated is carried out by an analyzing unit 26; a distribution curve corresponding to the wind direction deviation of the generated output power at each incoming wind speed is determined; the wind direction deviation corresponding to the peak of the distribution curve is set as a correction value θd of the anemoscope; the correction value of the anemoscope for each incoming wind speed is stored in the wind-direction correction table 27; the wind direction Vw measured at the anemoscope is corrected with the correction value θd of the anemoscope for each incoming wind speed Ws; and power-generation control is carried out using the corrected wind direction as a control parameter.

The invention discloses a helicopter rotor system capable of actively shimmying. The helicopter rotor system comprises a shimmying control mechanism, a universal joint connecting rod mechanism, a two-degree-of-freedom planar parallel constraint mechanism and an automatic inclinator, wherein the universal joint connecting rod mechanism transfers the rotation motion of a main shaft to a shimmying control table; the two-degree-of-freedom planar parallel constraint mechanism controls the plane position of the shimmying control table, so that the shimmying control table eccentrically rotates relative to the main shaft, and the aim of periodically controlling the shimmying amplitude of blades is achieved through a sliding block and a shimmying control connecting rod. By actively controlling the shimmying motion of the blades, the phase and amplitude of a shimmying motion period of the blades can be controlled. By virtue of the mechanism, the angular speed of advancing blades is greatly decreased, the angular speed of retreating blades is greatly increased, the advancing resistance and retreating stall of the blades in a high-speed flight state of a helicopter are effectively reduced, the fatigue load of the blades during alternation of advancing and retreating states is reduced, the helicopter rotor system actively adapts to various flight states of the helicopter, and the extreme flight speed is increased.