Wind Turbine

Thomas Grothe

Wind to Mechanical

• Pwind = (1/2)ρairAv3

• tip speed ratio = blade tip speed / wind speed• Optimal tip speed ratio when tw = ts (this is

when greatest possible amount of energy in the wind is used to rotate to rotor)

• ts = 2π/(nω) tw = x/v

Mechanical to AC

• Alternator uses induction to make 3-phase AC

AC to DC

• diode – allows current to go in only one direction

Battery

• apply a voltage that is higher than the battery’s output voltage

• charge controller puts extra current through something else

• industrial forklift batteries

120 V AC 60 Hz Output

• inverter – DC to AC

References

• http://www.windstuffnow.com/main/3_phase_basics

• http://www.otherpower.com/otherpower_wind.html

• http://www.scoraigwind.com/• A Wind Turbine Recipe Book – Hugh Piggott