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Author Topic: A strong permanent magnet and a small coil  (Read 14752 times)

Offline Liberty

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Re: A strong permanent magnet and a small coil
« Reply #15 on: August 27, 2013, 04:31:56 PM »
It was you that threw out the bold statement,not me. I just tried to tell you that it cannot be done.
A direct current cannot be produced by 2 magnets and a coil-full stop.
But i see you are now coming up with the excuses as to why you wont confirm your claim's-this is tipical of some one that CANNOT back up there claim's. We see this all the time,so no further discusion is required in reguards to your magic DC power plant.

@Liberty.
I have to disagree with what you said about it being pulsed DC. DC current flow's in one direction(if we are to use that term),while AC current alternates in both direction and voltage,and most of the time current aswell.
Your Quote:but what generators/alternators produce during power generation is actually only pulse DC, no matter what the configuration or type of generator/alternator.

Would you not agree that to get a DC current,we need to rectify,and also use smoothing cap's?
There are DC generator's(i have one),but it is not a smooth DC,but rather noisey and erratic without smoothing cap's. Now vehicle altinator's have built in diode's to rectify the current,but this is also not a smooth DC current until you hook it to the battery-even then,you can see the ripple on a scope when you draw a load from the battery(eg headlights on).

My point was that Magregus is talking rubbish,and now as you can see,he is looking for a way out-the excuses are flowing already.
But nothing out of the ordinary,as we see it time and time again, when people make claims they cannot back up.

What you have described is a varying DC voltage.  Yes, to have a smooth output, you may need to use smoothing caps on a pulse DC generator. Also you will need to use smoothing caps on a diode (rectifier) output from an "AC" generator, such as a car alternator.  But I still stand by my statement as true.  If you look at a pulse output from a coil on a o-scope, you will see the pulse is one polarity only, that varies in voltage, by an increasing flux flow or a decreasing flux flow in the coil, but it will not go into the opposite polarity unless you change the flux flow direction, coil polarity, or direction of motion.  Not to argue, just to give another perspective that appears to hold true.  Or if you will, a law of nature and physics.

Liberty

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Re: A strong permanent magnet and a small coil
« Reply #15 on: August 27, 2013, 04:31:56 PM »

Offline tinman

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Re: A strong permanent magnet and a small coil
« Reply #16 on: August 27, 2013, 04:59:44 PM »
  If you look at a pulse output from a coil on a o-scope, you will see the pulse is one polarity only, that varies in voltage, by an increasing flux flow or a decreasing flux flow in the coil,
Liberty
No,once again i disagree.
If you pulse a coil (switch on then off) the polarity changes,only the current flow remains in the same direction. Also an altinator is called an altinator because it produces AC(altinating current),by the switching of magnetic fields.It is then rectified to give an untidy DC current,which is sent to the battery.Most altinators are 3 phase AC,and the waveform will look like the one pictured below.As you can see,there is no DC there.

Offline Liberty

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Re: A strong permanent magnet and a small coil
« Reply #17 on: August 27, 2013, 06:19:10 PM »
No,once again i disagree.
If you pulse a coil (switch on then off) the polarity changes,only the current flow remains in the same direction. Also an altinator is called an altinator because it produces AC(altinating current),by the switching of magnetic fields.It is then rectified to give an untidy DC current,which is sent to the battery.Most altinators are 3 phase AC,and the waveform will look like the one pictured below.As you can see,there is no DC there.

(Speaking in respect to a single coil output).  For instance, a magnetic field approaches a coil, the output voltage will increase (say positive in relationship to zero voltage point) from the coil with current flow in only one direction (DC).  When the magnet leaves the coil, the current flow from the coil remains in the same direction (DC), but the voltage output starts from the peak voltage output, and decreases over time, as the magnet moves away, until it returns to zero output. (Varying DC output).  It will not ever have current flow in the opposite direction. (Voltage polarity remains positive (and therefore current flow) does not pass the zero point in respect to the zero voltage point on a scope).  If we are talking about a positive pulse in relationship to the zero volt point on a scope, it will not go negative or below zero.  Current flow remains in the same direction, which is a varying DC output, with current flow always remaining in the same direction.  In order to have an AC output, it must be manufactured by the alternator by using alternating magnet polarities or other methods that accomplish the same thing.  (Which will produce an alternating varying DC voltage output by passing by each alternating magnet polarity which creates current flow in an alternating voltage potential, above zero point, (positive voltage) returning to zero; then below zero point, (negative voltage) then returning to zero).  Which is an alternating current or AC sine wave that varies positive and negative voltage.  Current flows one direction, then reverses with AC.
    .           
  .   .            positive
.       .
_____ zero voltage point


                   negative

We are very close to agreement, but have different understandings of what a decreasing voltage pulse amounts to.  The voltage does not change polarity during a decrease in voltage pulse output from a coil, unless it passes the zero point, which would reverse current flow direction.  However, a diode can conduct on a decreasing power pulse, (even while remaining in positive voltage territory) whether the pulse passes the zero voltage point (becoming negative) or not.  In the pulse diagram, the polarity remains positive, yet increasing, then decreasing in voltage potential as the magnet leaves, but never goes below the zero point.   This is why generators/alternators technically produce pulse DC output or varying DC output.

 

Liberty

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Re: A strong permanent magnet and a small coil
« Reply #17 on: August 27, 2013, 06:19:10 PM »
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Offline Magluvin

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Re: A strong permanent magnet and a small coil
« Reply #18 on: August 28, 2013, 12:22:17 AM »
(Speaking in respect to a single coil output).  For instance, a magnetic field approaches a coil, the output voltage will increase (say positive in relationship to zero voltage point) from the coil with current flow in only one direction (DC).  When the magnet leaves the coil, the current flow from the coil remains in the same direction (DC), but the voltage output starts from the peak voltage output, and decreases over time, as the magnet moves away, until it returns to zero output. (Varying DC output).  It will not ever have current flow in the opposite direction.


I would have to disagree.

It sounds like you are talking about the rotor magnet inducing current in the coil, right?

When we use a scope to watch the output of the coil, with a complete pass of the magnet, there will be 1 AC cycle produced. Maybe we are forgetting the basics of producing current through a conductor using a moving magnet, or vice verse.

When the magnet approaches the coil, the magnetic field will be 'cutting' the approaching side of the winding first. This will cause currents to flow in those conductors, lets say up as the magnet is moved from left to right, causing a clockwise positive current flow in the coil. That half of the AC cycle will be at 0v 0A, when the magnet reaches the center of the coil....  Then when the magnet passes center, the magnetic field 'cuts' the departing side of the coils windings, again, causing current to flow 'up', once again, Faraday, but the current in the coil is now flowing counter clockwise, and the output will be negative. The reason the current goes to 0 current flow is because the magnets field is cutting both the approaching and departing side of the coil equally, where current in both sides of the coil want to go 'up', but they cant because of canceling, or better yet 2 equal charges facing each other at the top and bottom of the coil. ;)


Also, if you have 2 magnets passing the rotor, having one magnet N facing the approaching side of the coil, and a S magnet facing the departing side of the coil, now we will be inducing more of the coil at once, rather than just 1/2 of the coil at any given pass. Imagine 1 magnet passing just one side of the 'inductor' only, the induced currents may have to fight the inductance of the other side of the coil. So by doubling the magnets NSNS, more output should be had. ;) ;D


Mags
« Last Edit: August 28, 2013, 03:38:20 AM by Magluvin »

Offline Magluvin

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Re: A strong permanent magnet and a small coil
« Reply #19 on: August 28, 2013, 12:44:11 AM »
No,once again i disagree.
If you pulse a coil (switch on then off) the polarity changes,only the current flow remains in the same direction. Also an altinator is called an altinator because it produces AC(altinating current),by the switching of magnetic fields.It is then rectified to give an untidy DC current,which is sent to the battery.Most altinators are 3 phase AC,and the waveform will look like the one pictured below.As you can see,there is no DC there.

Hows it going Tin   ;)

"If you pulse a coil (switch on then off) the polarity changes,only the current flow remains in the same direction."

When you say 'polarity changes', are you talking about magnetic or electric polarity?

Mags

Free Energy | searching for free energy and discussing free energy

Re: A strong permanent magnet and a small coil
« Reply #19 on: August 28, 2013, 12:44:11 AM »
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Offline MileHigh

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Re: A strong permanent magnet and a small coil
« Reply #20 on: August 28, 2013, 04:34:30 AM »
Going back to the original topic, here is an excellent clip that explains why a coil needs to see changing magnetic flux with respect to time to generate some EMF:

http://www.youtube.com/watch?v=fJjVxR2fynk

Offline Magluvin

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Re: A strong permanent magnet and a small coil
« Reply #21 on: August 28, 2013, 06:37:31 AM »
Going back to the original topic, here is an excellent clip that explains why a coil needs to see changing magnetic flux with respect to time to generate some EMF:

http://www.youtube.com/watch?v=fJjVxR2fynk

Oh, I agree with all that. ;) I agree, so far, that just magnets attached to a coil physically, what ever the configuration, should not produce an output, because there is no changing magnetic flux or as I say, no field cutting the windings.  But what would happen if we had a particular configuration of magnet/coil module and move the coil and magnet as one through space? Through the air, or water?

If anyone understands the Faraday paradox, the magnet can be attached to the coil/conductor and when in rotation or we can say in motion, current is induced into the coil/conductor/copper disk.

There are many vids on YT of simple experiments done on lathes and there is current. The issue is the conductor being induced is a solid copper or aluminum disk. Ultra low ohms from the inner diameter to the outer edge, coupled with bad connections trying to make contact with the inner and outer portions of the disk, as typically shown.

So the answer to that problem is to have more resistance in our conductor being induced. We need a coil of wire with a magnet attached to it. ;) ;D   But that magnet cant be centered on the coil. And it would be better to have 4 magnets. while I was winding my coils for my Lasersaber ez motor build, I had quite a few coils that the wire broke while winding that I will try my idea out with. I tried this idea with an ecore, 2 mags and like 20 turns of 23wag. Nada as for lighting an led. But these coils have near 3000 turns of 42 awg and can light an led with just one of the magnets Im going to try, just passing it with the rotor at low speeds. So with 4 mags in my idea of configuration, there should be more output than just the 1 rotor mag at lesser speeds im thinking. Like a batteryless bicycle wheel light. While in motion, producing dc. I was going to lay it out here what the magnet configuration should look like. Before I do, does anyone want to take a shot at a guess of how it should be?   ;D   Ive already described it in basic form, the operation of the configuration in my previous post.

Lasersaber talked about something Tesla said about long wires. Like miles of it. He said that if you have that much wire on a coil, high voltages are easily produced with weak moving fields. Something like that.

So basically it is a redesign of a homopolar gen with magnets attached to the coil(s). We are talking about magnets and coils being 1 unit here, together physically, the only exception is that the unit as a whole has to be in motion.  If it produces current output but no drag, thats a good thing. if there is drag, then if we applied power to the unit, would that cause the unit to move, pushing itself against what ever it was dragging against? :o ;) ;D

What was found with the paradox was that even though the magnets were rotating with the copper disk between them, was that the fields between the magnets were not moving with the magnets, as the copper disk was still producing current because of the field 'cutting' the copper as it spins in motion, because the fields were stationary even though the ring magnets were spinning So it would seem logical that if we have copper between 2 attracting magnets and we move the unit through space, then current should be produced in the copper. ;D


But lets say we have a coil and we put a magnet dead center on the face of the coil, like if the coil were mounted on the face of the magnet while the magnet was on a rotor, we wont see any current due to my description in my previous post.

Just getting my motor setup for reed switch holders and do some testing. Then I will try the coilmag idea. If anyone wants to try to guess the config for the 4 magnets I have in mind, go for it. Ill tell tomorrow.  I just want to see if anyone gets my drift. Was looking for magnets today that didnt have metalic coatings. There must be some eddy losses there, possibly affecting motors we build. Just thinkin.

lol, just had a strange thought. If the unit in motion can produce current, we may not have to move it at all. The surface of the earth moves like 1000mph, lol, just aim east or west. lol. If that were so, then this thread would become very valid. ;D


Mags


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Re: A strong permanent magnet and a small coil
« Reply #21 on: August 28, 2013, 06:37:31 AM »
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Offline tinman

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Re: A strong permanent magnet and a small coil
« Reply #22 on: August 28, 2013, 01:19:35 PM »
Hows it going Tin   ;)

"If you pulse a coil (switch on then off) the polarity changes,only the current flow remains in the same direction."

When you say 'polarity changes', are you talking about magnetic or electric polarity?

Mags
Hey Mag's-fancy meeting you here lol.
I was refering to electrical polarity,as if it was the magnetic polarity,the current would change direction.
And spot on with post 18.
Here is a video i did some time ago showing this by using LED's,a coil and magnet.
http://www.youtube.com/watch?v=itP3QJ_-BL0

Offline tinman

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Re: A strong permanent magnet and a small coil
« Reply #23 on: August 28, 2013, 01:53:25 PM »
@ Mags
One would hope magregus knows the difference between a disc generator,and a generator that has coil's. I have tried using coils of wire insted of a solid disc ,in a homopolar setup-and it dosnt work.The free electrons either flow from the center of the disc/out, or from the outer edge of the disc/in. The magnetic field orientation determond's which way this happens,as dose the direction of rotation. So there has to be a straight line path from the center of the disc ,to the outer edge,and when we use coils ,that path is broken. Tesla had a design that had curved shaped disc segment's,and claimed that it would be a more efficient homopolar genrator.There have been quite a few replications of this design,and not one that i know of has produced anywhere near the current of that of the standard disc generator.

What is a coil
http://en.wikipedia.org/wiki/Coil

What is a disk
http://www.thefreedictionary.com/disc

So as we can see, a coil is not a disc.

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Re: A strong permanent magnet and a small coil
« Reply #23 on: August 28, 2013, 01:53:25 PM »
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Offline Magluvin

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Re: A strong permanent magnet and a small coil
« Reply #24 on: August 29, 2013, 12:34:54 AM »
@ Mags
One would hope magregus knows the difference between a disc generator,and a generator that has coil's. I have tried using coils of wire insted of a solid disc ,in a homopolar setup-and it dosnt work.The free electrons either flow from the center of the disc/out, or from the outer edge of the disc/in. The magnetic field orientation determond's which way this happens,as dose the direction of rotation. So there has to be a straight line path from the center of the disc ,to the outer edge,and when we use coils ,that path is broken. Tesla had a design that had curved shaped disc segment's,and claimed that it would be a more efficient homopolar genrator.There have been quite a few replications of this design,and not one that i know of has produced anywhere near the current of that of the standard disc generator.

What is a coil
http://en.wikipedia.org/wiki/Coil

What is a disk
http://www.thefreedictionary.com/disc

So as we can see, a coil is not a disc.

Hey Tin

When we look at the disk, it is a conductor just like a wire. When the magnet field is dragged across the conductor currents will flow. Imagine the disk made of a small copper ring in the middle and a large copper ring for the outer diameter and copper wire spokes from the inner ring to the outer ring. Now, we know that if we reverse the polarity of the magnets, or rotate the rotor the other way, we get reverse polarity electrically whether its a disk or spoked wheel. ;)

So are we restricted to only having currents flowing inward or outward through the disk or spoked wheel? Not if we break up the pattern of the disk and the magnet field. Lets say we get rid of the rings and we use plastic rings but still have the wire spokes.  Lets assume we have 100 spokes. Lets divide them into groups of 5 and for each group, 20 groups, and each group has its own magnet, all NSNS. Group number 1 has N mags, group 2 has S mags, 3 has N mags and so on.  We now have group 1 with currents going inward on the spoked wheel, and group 2 currents going outward, 3 inward and so on.  Now all we have to do is make all these groups with 1 piece of wire. We start at the inner diameter in section group 1 and string it outward, then string it over to group 2 and sting it inward, over to group 3 outward and so on till we end up at the beginning of group 1. Then we continue to wind that pattern till we have as much as we want.

Ive made a wheel with a similar config that Ill be testing this weekend.

As for the 1 coil with 4 magnets arrangement, imagine a stator coil where a rotor magnet N is facing the left side of the coil and a S is facing the right side of the coil. Now mount that coil to the rotor in that position. The other 2 mags will be mounted on the outer side of the coil, in attraction to the inner rotor magnets, causing very dense field concentrated in each side of the coil.

Ill post results when its done. Im just finishing my EZ spin version here and will do these tests with this motor as a platform. Will see what happens. ;D

Mags

Offline Magluvin

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Re: A strong permanent magnet and a small coil
« Reply #25 on: August 29, 2013, 04:36:23 AM »
Here is a visual of the idea. Its not hard to do.

If the Faraday dynamo can induce currents in the copper disk, with the magnet moving with the disk, then in the picture below, copper fat wire loop with magnets all moving as one unit in the direction of the arrow, we should get current in a coil mounted to magnets and putting them in motion, the green arrow. The field between the 2 magnets closest to the arrow would cause current to flow up or down, depending on the pole designations, and the part of the loop between the other 2 magnets should cause current to flow opposite of the front magnets. So current in the loop should flow. Now open the loop and we get very low voltage but high current capabilities, like the Faraday dynamo. So we replace this copper loop with a coil of fine wire to get that voltage up. ;) ;D

Mags

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Re: A strong permanent magnet and a small coil
« Reply #25 on: August 29, 2013, 04:36:23 AM »
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Online Pirate88179

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Re: A strong permanent magnet and a small coil
« Reply #26 on: August 29, 2013, 04:51:42 AM »
Mags:

Nice drawing.

I am assuming that the toroid shape is a solid piece of copper....right?  (as in Faraday's disk)  What if that circle were segmented?  Slice it into say 4 pieces and put back together with an insulator between the joints?  As it turns, you would have interruptions so, would that generate pulses?  If so, what would that do to the voltage/power?  The faster it was turned, the higher the frequencies.

Just brainstorming a little...it is possible that I am on the wrong track with your idea.

Bill

Offline Magluvin

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Re: A strong permanent magnet and a small coil
« Reply #27 on: August 29, 2013, 05:11:01 AM »
Hey Mag's-fancy meeting you here lol.
I was refering to electrical polarity,as if it was the magnetic polarity,the current would change direction.
And spot on with post 18.
Here is a video i did some time ago showing this by using LED's,a coil and magnet.
http://www.youtube.com/watch?v=itP3QJ_-BL0

Hey Tin.  ;D   I missed that post :(

Great demonstration.  ;)    If there is a core in the coil, the approaching and departing fields will be more dense giving more output, also the core shields the departing side of the coil from the approaching magnets field and it shields the approaching side of the coil while leaving the departing side of the coil. Like if you have a large magnet and an air core coil, during the approach, its fields are extending strongly into the coil as a whole, hindering output some, considering the extra weight of the mag and distance it has to go to get the job done.  All that may be confusing.

To understand it better, if you did the same experiment in your vid, but make a coil with a large inner diameter, where the approaching side of the coil is say a couple inches away from the departing side, the leds should only light when the magnet passes the windings, either the approaching or departing windings, and not much output any where in the middle, current wise.

And if we make a large inner diameter coil but only the up and down, not side to side, where we just put 2 nails in a table and wind on that so that the approaching side and the departing side are right next to each other, it would take a tall thin magnet passing in order for the field to cut only one side of the windings first then last, in order to get any appreciable output.

Looking forward to the pulse motor contest. Lasersaber should enter his. I wont enter my version as it is his baby and that wouldnt be right.  ;) But I have an odd idea I may try for entrance. :o ;D

Mags

Mags

Offline Magluvin

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Re: A strong permanent magnet and a small coil
« Reply #28 on: August 29, 2013, 05:32:10 AM »
Mags:

Nice drawing.

I am assuming that the toroid shape is a solid piece of copper....right?  (as in Faraday's disk)  What if that circle were segmented?  Slice it into say 4 pieces and put back together with an insulator between the joints?  As it turns, you would have interruptions so, would that generate pulses?  If so, what would that do to the voltage/power?  The faster it was turned, the higher the frequencies.

Just brainstorming a little...it is possible that I am on the wrong track with your idea.

Bill

Hey Bill

Yes, big copper doughnut.  ;D   Just for ease of description. It is looped just for simple visual. If we open the loop, we would still just get tiny voltage out, like the disk, due to very low resistance between the ends. So the more individual conductors in series, using a coil, the voltages should be up.

In that post, I said that the doughnut could be replaced by a coil of wire. The coil or even the doughnut does not rotate. The coil and magnet are fixed as one unit. Then it could be mounted to say a bicycle wheel to light an led when the wheel rotates. Or mount some on a rotor to move them in the direction of the arrow.

In Faradays original U magnet with a copper disk and brushes for contacts, imagine the fields between the U mag poles as strings. These strings 'cut' across the disk and produces current in the copper. Very low voltage but high currents.

But what is said is that if we have a copper disk and we mount a couple of big ring magnets, one on each side of the disk, in attraction, then the magnets actually move with the disk. But we still get current out of the disk. :o :o   So now, even though the magnets are in motion, we now have to assume that those 'strings' of field between the magnets are stationary in reference to the magnets moving. Otherwise the disk would not be being 'cut' by the strings if the strings moved with the rotating magnets. ;)

So in my picture above, why would we not have that same situation? The strings shouldnt move with our magnet/coil module. So if we move the module in either direction of the arrow, we should get current out of the coil. ;D

This idea I have had for some time and just recently have I come up with the simplest approach as shown above. Will see.

Mags

Offline tinman

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Re: A strong permanent magnet and a small coil
« Reply #29 on: August 29, 2013, 10:38:11 AM »
Hi Mags

I dont think all that string theory is correct. Like i said befor,you need to have a centrifugal force,and magnetic field to get the free electrons within the copper to flow. With your pic above-there will be no centrifugal force,as your arrow depics a straight line path. You need spin,just like the electron has,and it is my beleife that the magnetic field polarity and rotation direction determonds which way the free electrons spin. This is how we get the polarity between the center of the disk,and the outer edge.There is a very simple way to lift the voltage of a homopolar generator.First you groove the outer edge of the copper disc,so as it looks like a square wave looped back on itself.Then you fill the grooves with a non conductive/hard material-such as ceramic.
Now we can pull a pulsed DC from the disc with the brushes. The output is then sent to "say" a 1:20 transformer. This will give us a decent AC voltage to work with.

 

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