Up-wind type windmill and operating method therefor

A method of operating an upwind type wind turbine including a support structured and arranged to stand erect on the ground or on a ship, a nacelle supported by the support so as to be rotatable in a plane perpendicular to an axis of the support when the support is standing erect, a rotor having a plurality of blades, the rotor being provided at a front portion of the nacelle and being rotatable by a wind force when the nacelle is at an upwind position, machinery within the nacelle capable of being driven by the rotor, a main shaft for driving the machinery, the main shaft being connected to the rotor, a rotation driving mechanism between the support and the nacelle for rotating the nacelle, the rotation driving mechanism including a yaw motor for performing yaw control of the nacelle, and a yaw brake for braking the rotation of the nacelle, the method comprising:

• rotating the nacelle to a downwind position by the yaw motor to thereby maintain the rotor in a stand-by condition by the controller controlling operation of the yaw motor when a detected wind speed of wind acting on the blades is higher than a predetermined cutout wind speed and the main shaft is disconnected from the machinery, wherein the downwind position is between 90° and 270° from the upwind position;
• and
• releasing the yaw brake from braking the rotation of the nacelle and stopping yaw control by the yaw motor after said rotating of the nacelle to a downwind position by the yaw motor to thereby allow the nacelle to rotate freely according to a direction of the wind.

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, said machinery including an electric generator;
• 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;
• a power outage detector for detecting a power outage of said electric generator;
• 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, the downwind position being between 90° and 270° from the upwind position, said controller being operable to actuate a battery to power the rotation of said nacelle from the upwind position to the downwind position when a power outage is detected by said power outage detector, 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.

A method of operating an upwind type wind turbine including a support structured and arranged to stand erect on the ground or on a ship, a nacelle supported by the support so as to be rotatable in a plane perpendicular to an axis of the support when the support is standing erect, a rotor having a plurality of blades, the rotor being provided at a front portion of the nacelle and being rotatable by a wind force when the nacelle is at an upwind position, machinery within the nacelle capable of being driven by the rotor, the machinery including an electric generator, a main shaft for driving the machinery, the main shaft being connected to the rotor, a rotation driving mechanism between the support and the nacelle for rotating the nacelle, the rotation driving mechanism including a yaw motor for performing yaw control of the nacelle, and a yaw brake for braking the rotation of the nacelle, the method comprising:

• rotating the nacelle to a downwind position by the yaw motor to thereby maintain the rotor in a stand-by condition by the controller controlling operation of the yaw motor when a power outage in the electric generator is detected, wherein the downwind position is between 90° and 270° from the upwind position;
• and
• releasing the yaw brake from braking the rotation of the nacelle and stopping yaw control by the yaw motor after said rotating of the nacelle to a downwind position by the yaw motor to thereby allow the nacelle to rotate freely according to a direction of the wind.