Dynamo design with regenerative back mmf

In summary: Magneto ignition is the process by which the magnetic flux linking the coil to the magnets increases rapidly, causing an electric current to flow in the coil.
  • #1
Narayanan KR
76
4
disk rotor.jpg

In the above presented dynamo design, three snapshots taken during three instances during the rotor running.
In fig 1 the approaching magnet builds an induced voltage across the coil, however the circuit is still open, hence no current flows. In fig 2 when the rotor reaches TDC (top dead center) switch is closed leading to the flow of current into the load.
According to lenz law, this induced current flows so as to create north pole on the rotor facing side of the coil, and this will push the rotor away thus adding to the kinetic energy of the flywheel.
I wonder how the back mmf instead of braking the fly wheel, it pushes/propels the fly wheel, I hope you mates share your suggestions and critics on this idea, thank you.
 
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  • #2
Narayanan KR said:
View attachment 199294
In the above presented dynamo design, three snapshots taken during three instances during the rotor running.
In fig 1 the approaching magnet builds an induced voltage across the coil, however the circuit is still open, hence no current flows. In fig 2 when the rotor reaches TDC (top dead center) switch is closed leading to the flow of current into the load.
According to lenz law, this induced current flows so as to create north pole on the rotor facing side of the coil, and this will push the rotor away thus adding to the kinetic energy of the flywheel.
I wonder how the back mmf instead of braking the fly wheel, it pushes/propels the fly wheel, I hope you mates share your suggestions and critics on this idea, thank you.
Since no current flows in the coil while the switch is open, there is no storage of magnetic energy. Were you hoping that you found a viable Perpetual Motion Machine (PMM)?

Nice avatar, BTW. :smile:
 
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  • #3
berkeman said:
Since no current flows in the coil while the switch is open, there is no storage of magnetic energy. Were you hoping that you found a viable Perpetual Motion Machine (PMM)?

Nice avatar, BTW. :smile:
PMM?,I would never claim so. It was just a thought experiment performed within the rules of present physics and i was expecting an scientific explanation whether it works that way or not.
Even when coil is open it develops induced emf because of the changing magnetic flux linked to it, and the moment the load is connected across such emf current has to start flow.
 
  • #4
Narayanan KR said:
PMM?,I would never claim so. It was just a thought experiment performed within the rules of present physics and i was expecting an scientific explanation whether it works that way or not.
Even when coil is open it develops induced emf because of the changing magnetic flux linked to it, and the moment the load is connected across such emf current has to start flow.
How does current flow through an open circuit? Mate in 2...
 
  • #5
Narayanan KR said:
In fig 2 when the rotor reaches TDC (top dead center) switch is closed leading to the flow of current into the load.
At "TDC" the ##\Phi## is at a maximum so ##d\Phi/dt =0##. There is no EMF and no induced current.
 
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  • #6
@Narayan KR
You're approaching a 'magneto ignition'. Study up on that subject and you'll be better able to work your hypothetical machine in your head.

When you can explain its "E-Gap" in a couple concise sentences , please do. It'll both cement the concept in your mind and help other students of magnetics who stumble across this thread.

Did you make those nice drawings ?

old jim
 
  • #7
Narayanan KR said:
PMM?,I would never claim so. It was just a thought experiment performed within the rules of present physics and i was expecting an scientific explanation whether it works that way or not.
Even when coil is open it develops induced emf because of the changing magnetic flux linked to it, and the moment the load is connected across such emf current has to start flow.

As Dale pointed out, there is no emf and no current at TDC. But as the magnet moves away from TDC, there will be an induced emf and current in the coil. The coil mmf should try to "oppose the cause" of the induction i.e. it should try to stop the magnet from going away.
So the coil should attract the magnet and reduce its kinetic energy.
 
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  • #8
jim hardy said:
@Narayan KR
You're approaching a 'magneto ignition'. Study up on that subject and you'll be better able to work your hypothetical machine in your head.

When you can explain its "E-Gap" in a couple concise sentences , please do. It'll both cement the concept in your mind and help other students of magnetics who stumble across this thread.

Did you make those nice drawings ?

old jim
Yes sir..I did those drawings on MS Paint, and 'magneto ignition'...i believe it will be interesting.
 

What is "Dynamo design with regenerative back mmf"?

"Dynamo design with regenerative back mmf" refers to a type of design used in electric generators, specifically dynamos, that allows for the generation of electrical power through the use of a back electromotive force (EMF) that is generated by the magnetic field of the rotor.

What is regenerative back mmf?

Regenerative back mmf, also known as regenerative braking, is a phenomenon that occurs when the rotor of a dynamo generates an opposing EMF as it rotates, which results in the conversion of kinetic energy into electrical energy.

How does "Dynamo design with regenerative back mmf" work?

In "Dynamo design with regenerative back mmf", the rotor of the dynamo is designed to have a magnetic field that changes direction as it rotates. This causes the coils of the stator to experience an alternating magnetic field, which in turn generates an alternating current (AC) output.

What are the advantages of "Dynamo design with regenerative back mmf"?

One of the main advantages of "Dynamo design with regenerative back mmf" is that it allows for the conversion of kinetic energy into electrical energy, making it more efficient than traditional dynamo designs. It also reduces the wear and tear on the dynamo, increasing its lifespan.

Are there any limitations to "Dynamo design with regenerative back mmf"?

One limitation of "Dynamo design with regenerative back mmf" is that it requires a source of kinetic energy, such as the movement of a vehicle or machinery, in order to generate electricity. It is also not suitable for all types of dynamos and may require specific design modifications.

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