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Author Topic: RomeroUK Replication Muller Variant Device  (Read 137347 times)
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You beat me to it, Peter, congratulations!    I had secretly ordered  ratiometric hall sensors (4 of them, can go up to +/-4600 Gauss), and wanted to do exactly what you are doing.  I received my package on friday but didn't have time over the weekend, thanks to wattsup and his FAKE theories.    LOL    ;D    I spent all the time analyzing videos.   I also ordered a few latching halls for powering my motor.

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the UGN seems to be plotting exactly what it is seeing.

yes, and they are linear too!

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I have attached a scope shot of the UGN above a loaded gen coil and i still get the sameish waveform and amplitude of Gauss swing, i have used the spare hall to also mark TDC of the gen coil, now the phase of the magnetic field is not TDC from the magnet/core position, ...

The shift is real !   :)

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... but the weird thing is the amplitude of the magnetic field does not change if i unload the coil, so i will say this again why is the magnetic field in a loaded coil and unloaded coil exactly the same.?


Yeah, that is interesting.  Basicaly the loading just moves the phase back and forth.   Or just backwards.   but what would make it move "forth"  or ahead?    there's something to think about.   Answer?   Capacitor!    :)

EM
« Last Edit: 2011-07-19, 22:56:52 by EMdevices »
   

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Nice one EM glad i beat you to it though  ;D

Cheers WW it is so nice being able to see the field strength and polarity.

Now i need to add current phase into the equation somehow i should think that a carbon resistor across the coil should do, then i can compare magnetism and current phase.
   

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EM sorry i posted before you had finished.

It had not occurred to me that the phase shifts with the load applied against unloaded, i will try to do this tomorrow, I wonder if the phase varies with speed of rotation also or the amount of phase shift in degrees would be less at greater speed, i am guessing it will and this would then give zero fossil fuels a nightmare, because he tuned 2 coils to speed up the rotor but when he tries tuning the next 2 then the previous 2 would go out of tune, he would get stuck in an endless de-tuned state  :D he was promising OU by a couple of weeks ago LOL

Offcourse i can now get round that by using a pic to auto tune the cap value for each gen coil simply by monitoring the field phase.
   
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Keep in-mind that the plot from a hall sensor will not match the output of a coil. Not the waveform, anyway.

The upward plot of the hall output will be related to above zero on a voltage output and below zero voltage on the downward swing(of the hall output)( or vise-versa ).

The point is.... the passing rotor magnet should not cause a magnetic reversal. Since the rotor magnet magnetic force is roughly the same as either top or bottom stator magnet force, sticking the rotor magnet in between the stator magnets just causes the rotor magnet field to ' flatten ' while both stator fields are shoved up or down, but away. In other words... when the rotor magnet is in between the stator magnets there are two radial fields formed.

Those radial fields are polarized at the center and at the periphery of the radial field.

It might be interesting to see that with your sensor.

The motor doesn't need to turn to see what I described.

As for why the Gaussian plot doesn't change with load.... The above statements are already enough to start a post bombing war  :D  Relax. It is the way it should be.


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it is so nice being able to see the field strength and polarity

My favorite 'bitch'  ;D

Even though someone skilled in these arts can safely assume what the magnetic fields are doing, in almost any case, you should never assume. My favorite 'bitch' is that folks speak of magnetic fields and don't even have the proper equipment to measure them. They use a voltage or current probe/connection to measure magnetic fields ? ? ? Of course, we can just take the current and voltage readings and do the math  :o

Fine if you are repairing a power supply or flashlight ('torch' - to you Peterae  ;) ) or something else just as common.

 

 
   
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TDC = Top Dead Center,   

this is automotive terminology, when the piston reaches the TOP of the cylinder, literaly, and than the spark fires at little after or before TDC.   

In a rotor, we sort of know what Peter means by this,  it's when the rotor magnet alignes perfectly with the ferrite, so they both share the same axis for an instant.

EM
   

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Those radial fields are polarized at the center and at the periphery of the radial field.

It might be interesting to see that with your sensor.

I can certainly plot this with the sensor and see what i get, i think i am already seeing the pole shift but it should be interesting to zoom in a little and see how large it is and exactly where it's occurring.  O0
   

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I am guessing without a strong theory on this that i am not seeing a reduction in field strength with the gen coil loaded, because the energy generated in the coil is a product of cutting the lines of force and therefore no energy is taken from the overall magnetic field strength, the only purpose of the magnetic field is to couple the rotational force of the rotor and the coil, when the force lines are cut the energy generated in the coil is from the rotational force of the rotor and not the magnetic field, the stronger the magnetic field the more lines of force get cut, the bigger the induced energy and the stronger the coupling of rotational force to the rotor and hence it slows more.
   

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The scope shot below shows current on the green trace using a low ohm high watt pot across a gen pair of coils and yellow the magnetic field in the top coil this shows the current phase in relation to the magnetic field in the core under load.

Also for WW i found the zero G voltage of my UGN @ 2.97v
When the rotor magnet is TDC i get 4.52V and when the rotor magnet is farthest away i do indeed get a pole swing @ 2.69V which is below the 0G point

Also for EM
The magnetic field is only out of phase from the center of the core when the rotor accelerates or decelerates, i get a phase shift to the left for acceleration and a phase shift to the right during deceleration, i created the acceleration and deceleration by adjusting my low ohm high wattage pot, once the rotor speed stabilises the magnetic phase remains at zero TDC wether under a high ohm load or a low ohm load, so it's only a change in velocity that causes a magnetic phase shift  O0
   
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Ah!

Then you should see almost the same G signal with no stator magnets.

If so, my description is how I adjusted my very similar generator. The point was to minimize Lenz on magnet approach by presenting a radial field to each half of the coil pair at TDC.

   

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Sorry for the confusion WW so far i have not used any stator bias magnets
   
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Good show Peterae! O0

Perfect weapon and executioner.  I'm getting the pop corn and drink for the bias magnet part.  Both polarities, right?   :D
   
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Also for EM
The magnetic field is only out of phase from the center of the core when the rotor accelerates or decelerates, i get a phase shift to the left for acceleration and a phase shift to the right during deceleration, i created the acceleration and deceleration by adjusting my low ohm high wattage pot, once the rotor speed stabilises the magnetic phase remains at zero TDC wether under a high ohm load or a low ohm load, so it's only a change in velocity that causes a magnetic phase shift 


Peter,

this is extremly interesting!   You've motivated me to continue my exploration and research and to go ahead and hook up my Hall sensors.

EM
   
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Sorry for the confusion WW so far i have not used any stator bias magnets

Ok. Set my comments about radial fields aside until you have the stator magnets employed. I can't find any signs of weapon blows, yet  :)

As for the other... You are looking at something called 'motor slip'.

The inductive reactance will change with the slip since the stator impedance is the phase sum of the constant resistance and the variable inductive reactance.

When the motor accelerates the inductive reactance is high and impedance is mostly inductive. The stator represents a low, lagging power factor. When the rotor speed increases the inductive reactance of the stator goes down equaling the resistance.

In addition: The variation of load is the major factor for what you are seeing, not so much acceleration except while the rotor is lagging or leading the drive pulses.

So, what you described is pretty much how a conventional motor works  :)

It is so much more informative when you can see all aspects, isn't it?
   

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 :) Yes indeed i still have bias magnets to do yet 4 variations of.

WW thankyou for the explanation in a form that's easily understandable.

When i am doing the bias magnet tests should i sandwich the UGN between the top of the core and place the magnet of top of the UGN, if so there will be a slight gap where the wires come out between the sandwich. or should i place the UGN on top of the bias magnet or try tests with both.
« Last Edit: 2011-07-21, 09:15:13 by Peterae »
   
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My suggestion is to widen the mechnical gaps to make any measurement possible. The force magnetudes may be less this way but you will have a more complete picture with more testing options.
   

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Do you mean the gaps between the bias magnet and the coil core, if so then there is already a gap of about 5mm in the stator hole and then maybe 1-2mm thickness of washer on top.

Or do you mean widen the gaps between the rotor magnets and the coils or both
   
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I would remove the coils (with the stator magnets in position) and adjust all gaps so you can plot the fields at different stages of rotor/stator magnet relative positions.
The radial field (apparent null induction for the coil) will be centered between opposing magnets.

In addition to the usual, changing the angle of the magnetic flux through a conductor loop also causes current induction. This is not normally calculated for induction and would be a good thing to look for.
Imagine the coil output if all possible causes for induction are employed together  ;)
   

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I would remove the coils (with the stator magnets in position) and adjust all gaps so you can plot the fields at different stages of rotor/stator magnet relative positions.
This is not possible because my coils are glued in place, but i cannot see any reason why i could not make a mock up of a rotor magnet, air gap, then stator magnet and insert my UGN to find the neutral zone

Or just position the UGN in between coils

« Last Edit: 2011-07-21, 15:24:02 by Peterae »
   

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Just to complete the non bias stator magnet tests i thought i would try to capture the magnetic phase shift on camera, which was no easy task because i have to hold the periphery hall dead center and in exactly the right position to get a small marker pulse, anyway after some fiddling i managed it to a degree, i am now thinking maybe i am only getting a phase shift on deceleration, maybe i need to watch the video myself just to confirm.
Anyway in this video i am triggering on the UGN hall so the periphery is relative to it.



EDIT ok having watched it there does seem to be a shift on aceleration

[youtube]http://www.youtube.com/watch?v=QYPFZtIFuAs[/youtube]
   

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I managed to zoom in on one wave to see it a bit clearer

You can hear when it's speeding up and slowing down, i am doing this by adjusting the resistive pot load

[youtube]http://www.youtube.com/watch?v=KkY0l2Tpp8w[/youtube]
   
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This is not possible because my coils are glued in place, but i cannot see any reason why i could not make a mock up of a rotor magnet, air gap, then stator magnet and insert my UGN to find the neutral zone

Or just position the UGN in between coils



I agree but do include the trigger magnet as well. Perhaps you should leave the trigger magnet out at first.

Loaded coils will have an effect upon any magnetic fields you see. This effect may not be visible without the odd rotor/stator magnet combination.

My opinion is one should have a clear picture of the field interactions before worrying about what the coil will change.

   

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I thought i would go ahead first and see what happens when i add bias magnets.

In these 2 videos you can see what magnetic field i get on top of the core with first a north up bias magnet on top and bottom stator coil and then second south up top and bottom.
Towards the end of each video i start sliding away the magnet from the washer to show the effect it has, this is done on the top bias magnet only.
I have include a photo to show the setup, you can also see the 25 watt 1K pot which is set to short for a starting point and minimun revs.

North up
[youtube]http://www.youtube.com/watch?v=0MhzRdVaROs[/youtube]

South up
[youtube]http://www.youtube.com/watch?v=Dv3FdmF95UQ[/youtube]
   
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The Hall was between the stator magnet and washer in both videos?
   

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The legs of the hall are bent 90 degrees so the flat face of the hall lays flat on the surface of the coil core i pushed it through the drilled perspex hole until it butts to the core, you then have a gap of about 2-3mm before the perspex surface is reached then 1-2 mm of iron washer then another 2mm spacer to allow the wires to come out from the hall then the magnet is placed on top of this.

see attached rough sketch
« Last Edit: 2011-07-22, 12:48:31 by Peterae »
   
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Ok. Then the waveforms make sense... except..

When you said 'North up' and 'South up' did that include the rotor magnet? I believe either orientation of the stator magnets requires an opposing orientation of the rotor magnet.

The waveforms indicate the rotor magnet was always in opposition.
   
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