Use vibration to generate electricity

[comewithcws]

Hello, I am a student making a generator.
the main idea is to use the vibration with the magnet coil setting with the spring to generate electricity.
I will use the permanent magnet, but i know that
e = N w B A
i decided to have a 12Volt output,
constant vibration frequency in 100Hz
the A is in circular,with diameter = 6cm(just roughly decide,can be change, but can't be too large)
but i didnt decide the number of coil (N) and the (B)
i hv no idea to choose how strong of the magnet should be.
or
may i ask that , in a resonable way, how lagre of the magnet i need to use to do this generator?

thankyou for your attention

 

[Bob S]

Read about and understand the effect of the spring constant k, magnet mass m, and damping on vibration energy harvesting in

http://en.wikipedia.org/wiki/Vibration

The resonant frequency is f = (1/2π) sqrt (k/m)

Also look at vibration energy harvesting using piezoelectric crystals at

http://www.linear.com/pc/viewCategory.jsp?navId=H0,C1,C1003,C1799

Bob S

 

[pantaz]

Here is a device very similar to what you're describing:
http://www.popularmechanics.com/science/energy/solar-wind/4224763?series=37

"Frayne's device, which he calls a Windbelt, is a taut membrane fitted with a pair of magnets that oscillate between metal coils."​

 

[Bob S]

The motion of the magnet relative to the vibrating mount is maximum when the resonant frequency of the spring (spring constant k) with mass m is tuned to the driving frequency of 100 Hz.
f₀ = (1/2π) sqrt (k/m) = 100 Hz. See thumbnail.

Bob S