Wind Turbines
Gear Box is one of the most crucial component of a
wind
turbine. As can be seen from the image given below a gear box is
placed between the main shaft and a generator. Gears also provide a
connection between a low-speed shaft to a high-speed shaft. The essential
duty of gears in a wind turbine is to increase the rotational speed of the
rotor blades. The rotational speeds are about 30-60 rotations per minute,
which the gears change to generation speeds of about 1000 to 1800
revolutions per minute(rpm). This is the rotational speed needed by wind
turbine generators for producing electricity. In the case of gear boxes of a
wind turbine, the gearbox maintains an uniform a speed increasing ratio. So
it is not the gear box of an automobile where it is used to increase the
speed.
Planetary Gear Box
Wind turbines of 450 KW or more uses an integrated planetary gearbox. It
comprises of a planet gear along with two normal stages. The planet gear is
a very unique form of toothed gear. The form of planet gear that is used on
wind turbines comes with a similar basic design. They are:
- Ring wheel: Interior toothed gear wheel.
- Planet Wheels: Three numbers smaller toothed gear wheel.
- Planet Carrier: The common carrier arm which carries the above three
wheel.
- Sun gear wheel: A centrally placed toothed gear wheel.