Sharing ideas on how to make a more efficent motor using Flyback (MODERATED)

[gyulasun]

People tend to neglect preciously listening to details.  When input current is switched on at a moment,  from that moment on till 5 times L/R time the current increases and magnetic field in and around the coil also increases in strength.  After the 5*L/R time elapses, a steady current flows in the coil and its magnetic field settles at a constant value.  (R means the total DC resistance of coil and its closed circuit via the battery and the energy content of the field is E= L*I*I/2  where I is the instantaneous value of the current, L is the coil inductance.)

When you switch off the current, the magnetic field starts to collapse. This means if it was just increasing in strength, then it suddenly starts decreasing in strength but it cannot change its earlier poles at the coil's end: what was North pole at one end it still remains North pole, just the intensity of the North pole reduces drastically at the moment of the current switch-off.

This flux change i.e. from an increase to a decrease direction  (or from a steady state value to a much lower value down to zero) of same poles is which flips the induced voltage polarity across the coil with respect to the voltage polarity the input battery established.  To compare this increase-decrease field change, imagine you approach a magnet towards the end of a ferromagnetic core (no coil is needed for this comparison) and then you stop the magnet say 2mm from the core then you start to move the magnet away from the core along the same straith line the approach happened, then the change of the magnetic filed strength in the core represents the event that happens when you switch the current off in a coil.  The rest of the process is also included in Tinman's nice explanation in his above post, no need to repeat.


Dear MileHigh,

you wrote:

"There is a somewhat ironic situation happening.  This thread is about a "more efficient motor" and only myself and Tinman have mentioned that the high-voltage coil has a relatively high resistance and that means more losses."

Well, please be more attentive because I also wrote about the 210 Ohm DC resistance as a loss in the HV coil in Reply 11, in the last but one paragraph, just after Laurent showed his first video replication:

http://overunity.com/16167/sharing-ideas-on-how-to-make-a-more-efficent-motor-using-flyback-moderated/msg465969/#msg465969 

Of course I do not consider this forum as a pissing contest, just I ask you to be more attentive, that is all.
One more thing: Laurent just tested the concept as he said and obviously  did not design for low loss, I think he just used coils, components at hand.

Thanks,
Gyula

[woopy]

Hi all

Yes very intersting development here, thank's to all for participating.

As i have the motor , i spent some time to place a 1 ohm current sensing resistor all arround the flyback ciscuit.

1- direct in the flybackspike just between  the output of the main (low voltage) coil and the diode, there is a very very narrow and strong current spike (peak at arround 1.3 A ) directed from coil to diode
2- Almost the same between the diode and the cap entry, but just after the spike,there is a very small and wide "opposed direction" current trace followed by   very little ringing (difficult to say because the trace is noisy)
3 almost the same between the output of the cap and the entry of the main (low voltage ) coil,
4- between the entry of the cap and the high voltage coil (assistant) there is a very small and wide current trace corresponding to  (2) or the discharge of the cap in the assistant coil.

So this confirm what Timan showed in his graphic.

Now the fact that there is almost no ringing, confirm also that the high voltage coil seems to  prevent almost totally the resonance of the tank circuit and maintain the slow and regular discharge of the cap which provide the usable secondary pulse .

So we will see if Tinman can get the same or better result with a lower voltage assistant coil.

Just for info i have tried to calculate the average power of the pulse  of the main coil and the assistant coil.  (calculation of the pulse duration only ,not the complete cycle) As said this  is quite difficult because the noisy trace of the very low current input in the assistant coil.

I have edited this part because i have to redo my calculation, because the main pulse and his son ( the pulse of the assistant Coil) are not of the same duration.


Hope this helps

laurent

[synchro1]

Bub

No, the current dose not revers polarity in the primary inductor-only the voltage dose.
You have confused current flow direction with current flow path.

OK,i will try one more time.
Please see attached pic below.
Diagram at top shows conventional current flow when reed switch is closed.
Diagram at bottom shows conventional current flow when reed switch opens.
As you can see by the red arrows,the current continues to flow in the !same! direction through the primary coil when the reed switch opend. You only have to look at the diode direction in the picture you posted of Woopy's circuit to see that this is true. If the current flow reversed as you say,then the diode would have to be turned around in order for that flyback current to flow into the cap/inductor combo on the secondary.

The cap will charge first with the flyback current,as it has a lower series resistance than that of the high turn coil. The cap will then start to discharge into the secondary coil as it reaches peak volatge. This is the reason for the !almost! linear discharge through the secondary coil,and the absence of resonant oscillations.

Hope that clears things up.

@Tinman,

There's no path back to the positive electrode for the reversed current with the Reed switch open. Positioning the diode at the top of the coil and connecting it to the positive electrode would send the current in the other direction backwards through the Primary to source. The destination determines the current polarity. The negative ground is the destination of the power pulse; Then the reversed current polarity seeks a positive ground!

You caused this same kind of confusion in that Universal motor schematic you passed to Chris Sykes on the bucking coil thread.

Charged capacitors resist change in voltage just like inductors. The sitting charge on the capacitor would determine the destination of the flyback, either through the inductor or to the cap. The LC tank is not isolated but part of a magnet rotor charging system. The spinning magnet rotor is causing a "Lenz Related" issue with the inductor that's outside the other factor. One the other or both, the flyback causes the capacitor to discharge into the Hi-voltage coil to accelerate the magnet rotor with a power pulse.

You're trying to maintain that a current can exist with a reversed voltage polarity. This is impossible! The current changes direction headed towards an opposite ground albeit by a circuitous path. The path is illusory, the direction of the current is switched from negative to positive inside the primary after the magnetic field collapse.

[gyulasun]

Hi Laurent,

I indicated with red X where I think you meant the positionings of the 1 Ohm resistor around the circuit, please correct me if I made any mistake and I will redraw it.

Would it be possible to take photos (snapshots) of the 4 waveforms on the scope you described in points 1 to 4? That would be better for everyone I suppose.

Thanks
Gyula

[minoly]

I wish I was coming to new understandings however I'm still having problems grasping the terminology.


A lot can happen in 24 hours of missed reading... I notice many are off topic. Tinman - thanks for trying to explain how a fluxgate can make a motor work to me. I'm so new to that terminology though, I'm hoping someone can break it down for me in simple step by step terms.


This is what Luc is trying to do right? Luc is not taking the spike from a coil on a rotor and then putting it to another coil to make it spin faster. He is using a fluxgate to make a motor work. However, I've looked up fluxgate and still can not figure out how to make a motor work with one.


So, putting the spike to a "high voltage coil" makes the coil stay magnetized longer which can electromagnetically hold onto a load longer, which has it's own uses, but I can't think of how to make a fluxgate make a motor work. Perhaps stronger at slower speeds? More torque? Or am I completely off and is what Laurent is doing exactly what you are after?


Can someone point me in the right direction as I believe this is the topic?

Yes Shylo, great thread!

Please feel free to share more if you can as 5x more sounds very interesting.

I'm very happy to see everyone's participation and some of us coming to new understandings.
Even if my ideas don't improve a motors efficiency we will all come out of it with something which should be the spirit of this forum.

Thanks to all for sharing

Luc