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.