# Generators Work...

Discussion in 'General Electronics Discussion' started by Moha99, Jun 4, 2012.

1. ### Moha99

261
0
Nov 18, 2011
Hallo all!

In a generator when energy is applied to it it causes the roter to spin the magnets through copper windings to convert mechanical energy to electrical.

Magnets produce a magnetic field on the copper windings that result in the conversion. Can I calculate that conversion in this form: W = F x D

Where F is the force provided by the magnetic field of the magnets
and the D based on the revolutions per minute that would give me the output of the system is that possibile to do?

Finally if I increased the amount of magnets in the system the force would increase right? that results in a higher output lets say we added magnets 2 times more

W = (2)F x D, the energy output would be higher right?

Hope I'm making sense...Thanks in advance
Moha,

2. ### duke37

5,364
772
Jan 9, 2011
That seems about the right principle, however the equation is:-

Power (W) = Torque (N.m) * Speed (radians/sec)

This is the power going into the machine, you will get less out.

3. ### Moha99

261
0
Nov 18, 2011

I converted the generators rpm rate to meter/s, in my case I have magnets with a pull force of 20 pounds of pull force(lb) converted that to newtons = 88.964432 N x D(What is it in this case? the distance between the magnets the copper windings?) X R(Radians what is that in my generator?)

*I can add another layer of magnets it can fit without making a problem for the roter so that would be 20 x 2 = 50 lb's of pull force.*

Thanks!

4. ### duke37

5,364
772
Jan 9, 2011
You make life difficult by not using SI units.

A radian is a measure of angle. There are 2*pi radians in a circle.
To go from RPM to radians/sec, multiply RPM by 2pi and divide by 60.

Torque is a measure of tangential force times distance from the rotary axis. I do not see how you find this value without experiment. A static force will not generate power, a variation in force is necessary. There may be a large static force but the important measure is the variation in force as the magnets pass the pole pieces but I do not understand magnetic circuits.

5. ### Moha99

261
0
Nov 18, 2011

Thanks. I'm starting to build up a permanent magnet generator and I'll use you're explanation to work out the process.

Any more inputs will be much appreciated!