The Workingsof a Wind Power Plant

Parts of the Plant

blade

generator

tower

foundingstransformer

http://www.motiva.fi/myllarin_tuulivoima/windpower%20web/fi/kids/index.htm

The kinetic energy of air is transferred into electricity.

source: glogster.com

The Power of a Wind Energy Plant

An air cylinder whose length is h=vt flows intothe blades in time tThe volume of the air cylinder V is then V=Ah=πr2vtThe mass of the air in the cylinder m=ρairV=ρairπr2vt

Starting from the efficiency, the output power is...

Conclusions

As can be seen from the pattern above, if...● r (length of a blade) doubles, the output power

quadruples (becomes 4 times bigger than what it was)

● v (speed of wind) doubles, the output power becomes 8 times bigger than what it was

The Generator

● transforms kinetic energy into electricity

● is based on electromagnetic induction– A moving magnet causes magnetic fields that are

constantly changing. This change of magnetic flux causes a voltage in any conductor!

– In wind power plants it's wind that spins the magnet or actually the conductor itself.

photo: Roosa Unelius

The Generated Voltage

𝑒=−𝑁𝑑Φ𝑑𝑡

𝑒=−𝑁𝑑 ( 𝐴𝐵 cosϕ )

𝑑𝑡

𝑒=−𝑁𝑑 [ 𝐴𝐵 cos (ω𝑡 ) ]

𝑑𝑡

𝑒=−𝑁𝐴𝐵𝑑 cos (ω𝑡 )

𝑑𝑡

𝑒=−𝑁𝐴𝐵ω [− sin (ω𝑡 ) ]

𝑒=𝑁𝐴𝐵ωsin (ω𝑡 )

𝑒=𝑒0 sin (2 π 𝑓𝑡 )

time

voltage

Presentation by

Dani and Jasu

Finnish Comenius team

Erkko-lukio

2013

This project has been funded by the European Commission. The Commission accepts no responsibility for the contents.