A wind turbine that uses a "direct drive” generator can generate electricity at much lower speeds. Direct drive systems do not require a gearbox and have fewer moving parts. This is an image of a wind turbine created by a middle school team that created blades by using Tinkercad to design the blades and then 3-D printed each blade.
Wind turbines that use generators connected to gearboxes will see their turbine's rotational blade speeds go from about 5–15 rotations per minute to higher speeds (1,000–1,800 rotations per minute). Turbines that use a gearbox will have more moving parts, making the gearbox one of the highest-maintenance parts of a modern wind turbine.
The drivetrain is the “powerhouse” of a wind turbine, containing the generator and gearbox which converts the torque—or rotation of the blades—into electricity. Learn more at Advanced Wind Turbine Drivetrain Trends and Opportunities.
What are gears? Gears are wheels with teeth. A gear train is made of several gears that mesh together.
On a wind turbine, a gearbox is typically used to increase rotational speed from a low-speed shaft where the blades are connected to a higher speed electrical generator.
Ralph Pugh, a Makersmiths member with an engineering background, explains the different kinds of gears, their functions, and how using gears in our KidWind wind turbine will benefit its performance. His presentation is entitled, Understanding Gears, Fun with Gears.
Wind turbine gearbox.
Cleaning a wind turbine gearbox. The image is from stingraypartswasher.com
Key vocabulary to know:
driving gear is the one connected to the wind turbine blades
driven gear is the one connected to the generator
gear ratio (driving gear teeth): (driven gear teeth)
shaft is the rod that connects the wind turbine blades to the gear box that connects the gears in the gear box to the generator.
Purpose of gears: Changes speed, direction of motion, torque (force). In a wind turbine, gears change speed.
Learn to create your own gears with Gear Generator.
Ralph Pugh's lesson on creating a gearbox for the wind turbine: https://docs.google.com/presentation/d/1S5BmiaaFF2LK3F0ZJJlAdv-oW8g_tnjV9F2M5-GBtDE/edit?usp=sharing
KidWind Turbine assembly movie.