Generators and Electric Motors
The most important part of any wind turbine is the generator. This is a device that converts mechanical energy into electricity.
Electric motors typically do the opposite, and use electricity to turn a motor shaft.
This means that an electric motor can also be used as a generator, and some electric motors make fantastic generators for wind turbines!
Typical motors that work well for a wind turbine are:
- Stepper motors - work well for low power applications
- Treadmill motors - widely available online
- Washing machine motors - high power output for large turbines
All of these can be found by taking apart old electrical equipment which is often thrown away with no consideration of the parts inside.
When considering whether a motor is suitable for a wind turbine you should look at the specifications for:
- Alternating Current (AC) or Direct Current (DC)
- Number of phases
- Rated power, measured in Watts (W)
- Rated voltage, measured in Volts (V)
- Rated speed, measured in Revolutions Per Minute (RPM)
Power and voltage are quoted at a particular motor speed, that is, if you supply the motor with the rated voltage, the shaft will turn at the rated speed. This can give an approximation of how the motor will act as a generator. Slight differences in performance occur due to efficiency losses.