Patent ID: 7436083
Filing Date: 2008-10-14
Classification: F03D,Y02E

Abstract:
1. An upwind type wind turbine comprising: a support structured and arranged to stand erect on the ground or on a ship; a nacelle supported by said support so as to be rotatable in a plane perpendicular to an axis of said support when said support is standing erect; a rotor having a plurality of blades, said rotor being provided at a front portion of said nacelle, and being rotatable by a wind force when said nacelle is at an upwind position; machinery within said nacelle capable of being driven by said rotor; a main shaft for driving said machinery, said main shaft being connected to said rotor; a rotation driving mechanism between said support and said nacelle for rotating said nacelle, said rotation driving mechanism including a yaw motor for performing yaw control of said nacelle; a yaw brake for braking the rotation of said nacelle; and a controller for controlling rotation of said nacelle by said yaw motor to a downwind position to thereby maintain said rotor in a stand-by condition when a detected wind speed of wind acting on said blades is higher than a predetermined cutout wind speed and said main shaft is disconnected from said machinery, the downwind position being between 90° and 270° from the upwind position, said controller being operable to stop yaw control by said yaw motor and release said yaw brake after said nacelle is shifted to the downwind position by said yaw motor to thereby allow the nacelle to rotate freely according to a direction of the wind.