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Convert magnetic to electrical?

I am trying to find a practical way to build a device to convert magnetic energy into electrical energy, some kind of generator or other device, there are several ways in which this might work in theory but actually building the device would be more difficult to figure out.

iceng2 years ago
There is a chem-cal device Cnair  that rapidly generates a very powerful
magnetic impulse ( _/¯\_ Rise and fall ) that you could use.

The ch-mical is a solid expl-sive like C4.  See the pics of some artistic
impressions to give you a conceptual visual minds eye.

The operating principle is very rapid mechanical shorting of coil wire turns while they the coil wires are conducting a large electric current.

This is accomplished by winding a suitable magnet wire on a conductive cylinder.
Terminating the wire at the cylinder end and starting a
deformation of the cylinder at the opposite end.  

The deformed progression of the cylinder shorts the wire at the explos-ve rate of travel generating an emp of substantial energy.

A
Flux_compression_generator_1.pngFLUeXplode.jpg
thedriftcore (author)  iceng2 years ago
This is the closest answer I have to what I was asking and has added several ideas to my (previously empty) list of ideas. So, if I understand it correctly, the magnetic field is compressed as a result of the explosion causing a short circuit in the wires of the device, causing a sharp spike in magnetic and electrical energy, thereby generating a strong electromagnetic pulse. The energy of the compressive force caused by the explosive is also added (to a certain extent) to the power of the field being generated, causing a spike in energy that can rival or even dwarf that of a lightning bolt. This principal could probably be applied in other ways that could result in a slightly different energy field being produced, this has really jump started my thinking process. Thank you for taking the time to answer.
Correct Understanding :)
VinylLady1 year ago
Have you taken a look at United States Patent #4,151,431?
It's by Howard R. Johnson regarding a Permanent Magnet Motor.
You also might find interesting his offering on a Magnetic Force Generating
Method and Apparatus Patent #4,877,983 or his Magnetic Propuslion System
Patent # 5,402,021. I lack the background in electrical/magenetic engineering
to understand them but surely someone does!
Thanks,
VL
thedriftcore (author) 2 years ago
What I'm talking about is actually extracting the energy of the magnetic field itself, similar to how a ferrous core in a coil of wire temporarily stores a small amount of energy in the form of a magnetic field when electricity is passed through the coil, which is then released when the coil collapses. I am not trying to find a way to use magnets to convert mechanical energy into electricity. Since it takes too long for the magnetic field of most magnets to collapse, I'm looking for a way, chemically or otherwise, that can hasten this process and allow the magnetic, not mechanical, energy to be converted into electrical energy.
You can't do that - the answer would be electromagnets but you already discounted that approach.

Rotating the magnetic field is a way to move it - you can't cut off a permanent magnetic field and then restore it
thedriftcore (author)  rickharris2 years ago
I don't need to restore the field, that would be getting energy from nothing, obviosly impossible. I just need to extract the magnetic energy itself and convert it to electrical energy, and while the energy is released naturally, a permanent magnets field will almost always eventually fade, it happens to slow to be of any use, so all I really need to know is a non-mechanical way of speeding up this process.
OK in that case no there isn't a way to do this unless you invent it.
thedriftcore (author)  rickharris2 years ago
Alright. Well, thank you for your time and answers, you have been very helpful.
Supposing you want to take a permanent magnet, and extract the energy from it somehow, so that at the end of this process you have a lump of material with no magnetic field, and you have the energy the magnetic field used to contain moved somewhere else.

I think a good place to start would be to calculate the actual amount of energy (in joules) stored in the permanent magnet's magnetic field in the first place.

http://en.wikipedia.org/wiki/Magnetic_field#Energy_stored_in_magnetic_fields

The answer might not be what you expected.
thedriftcore (author)  Jack A Lopez2 years ago
I understand that, but I still am unable to think of a way to extract that energy without putting in more energy than you would receive. In heating the magnet to collapse the magnetic field more quickly, you would normally require a greater amount of energy in the form of heat then you could extract from the field itself, and in moving/shaking the magnet to disrupt the magnetic field lines and hasten the collapse of the magnetic field, you would need to input a larger amount of mechanical energy. are there any other ways in which you can collapse/extract the energy from a magnetic field without putting in more energy than you are receiving (not counting the energy put into the magnet, since there isn't free energy of course)?
Are you under the impression that there is a large amount of energy present in the field of a permanent magnet?   I think the answer is going to be just a few millijoules per gram of magnet material.

I mean why worry about it if there's not a significant amount of energy there to extract?
thedriftcore (author)  Jack A Lopez2 years ago
Like I said, I understand the amount of energy that is found within a magnetic field, I just need a way to extract it, or a method of speeding the natural collapse of the magnetic field that doesn't use mechanical means.
rickharris2 years ago
This is what a generator does.

Moving a wire in a magnetic field generates electricity - OR moving the magnetic fiel round a stationary wire also produces electricity

So your question is?
thedriftcore (author)  rickharris2 years ago
More specifically, how do you convert the magnetic energy itself into electricity without the assistance of motion? If a magnetic field collapses it can produce a current in a nearby wire without any mechanical motion. Most magnets have a field that will eventually collapse, however this takes a very long time for most permanent magnets, so I am looking for either a way to hasten the collapse of the magnetic field or a different way to convert that magnetic energy into electricity without any mechanical movement.
kelseymh2 years ago
It's called a generator, and they've been around for about 170 years.
thedriftcore (author)  kelseymh2 years ago
I'm talking about extracting magnetic energy, not using magnets to convert mechanical energy. Different principle and energy source entirely.