Hi,I hope someone can help me. Looking at a magnetic generator,

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The discussion focuses on calculating the induced EMF from a magnetic generator design featuring a rotating ring of magnets and static copper wire coils. The user seeks a formulation to determine the EMF based on various factors, including the size and number of magnets, the number of wire windings, and the air space between components. Key considerations include how changes in magnet size and surface area, coil thickness, and the number of coils affect EMF output. The user expresses a desire for clear explanations of the relevant symbols and concepts related to electromagnetic induction. Overall, the inquiry emphasizes the need for guidance in understanding the principles of magnetic generators and their performance metrics.
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Hi,

I hope someone can help me. Looking at a magnetic generator, we will have a ring of magnets which will rotate, and then we have the copper wire static.

I understand that if I have a ring of alternating magnets, all placed right next to each other, thereby creating a solid magnet surface for the copper wire to rotate against, the formulation for calculating the induced EMF = 2 x length into paper x radius to wire x Radial Flux Density B from magnets x rotational speed.

Please see attached picture. The outer diameter is 300 mm and the height 50 mm. This design is different, as I have only 24 magnets, with a radial flux density of 1.4 Tesla. I think their size is approx length (29 mm) x width (14 mm) x height (50 mm). I then also have 18 copper wire coils.

Is there a formulation I can use to calculate the possible EMF I can expect from this design? Also, how do I calculate how many magnets

I need some help here, but I would like to be able to calculate how the EMF will change when I:

1) Increase or decrease the size of the magnets (I expect here that the surface area of the magnet that get in contact with copper will have an effect)
2) Increase or decrease the number of windings in one coil and thickness of the copper wire
3) Increase or decrease the amount of magnets
4) Increase or decrease the amount of coils
5) Increase or decrease the air space

Most of what I know by now I have learned on the internet or with other help, so please treat me kindly! I do not understand most of the symbols in formulations, so if you can help with a formulation with explanations of symbols, like with EMF above, that will be awesome!
 

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I'd try the electrical engineering forums if you don't get any hits here. I'd help but I don't know enought to answer your questions!
 


Thanks, I will repost now.
 


barendfaber said:
I need some help here, but I would like to be able to calculate how the EMF will change when I:

1) Increase or decrease the size of the magnets (I expect here that the surface area of the magnet that get in contact with copper will have an effect)
2) Increase or decrease the number of windings in one coil and thickness of the copper wire
3) Increase or decrease the amount of magnets
4) Increase or decrease the amount of coils
5) Increase or decrease the air space

2)increase the number of windings in one coil -- i think this will cause greater magnetic field
3) amount of magnets??
4)the same with #2
5) i don't know

read more about ELECTROMAGNETIC INDUCTION.. i think these are basics concepts under these topics but i forgot about it so, i might as well give wrong info if i would just recall. I really am not that sure.. hope you'll be patient reading :)
 
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