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Author Topic: The Non-Sense Pulse Motor.  (Read 83465 times)

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Thinking further, the only thing C1 does is supply an instant high current at a very low duty cycle,in this case it is a good thing as it is current that creates the field in the coil, but at longer duty cycles it may as well be removed.

Regards

Mike 8)


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I believe you're very, very close to finding the answer.

How would reducing the capacitance of C1 affect the
current magnitude distribution?  If C1 were to be quite
a lot smaller for example?

It certainly does look like all of the Inductive Kickback
is dedicated to illuminating the LED array.


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I made a quick replication of Tinman his magnet/coil setup in order to take some measurements.

Using a 2.7mH / 2.6 Ohm coil i had laying around.

Screenshot shows:

yellow: battery voltage (12.35V, not shown due to scopes limitation of 4 measurement points only).
Purple: CSR1 (10 ohm) signal 15.68mA mean
Red:    math function (yellow x purple) 189.2mW input mean.

Blue:   CSR2 signal
green: current probe signal in C1 minus lead.

Video also shows input power calculated by using DMM's for voltage and current (196mW).

Video here:  https://www.youtube.com/watch?v=xTDG_xs8FNU


Itsu
   
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... .-.. .. -.. . .-.
Thanks for the files Jim.
Can confirm the rotor file is editable, when logged in :)



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Like I have altered below.

How you have it CVR1 is measuring to C1 when you have a low duty cycle, as you increase the duty it will start to measure to the coil as well because the C1 can't supply sufficient.
When it is a short duty the power comes just from the C1, C1 gets charged when the transistor is off and not supplying to the coil.

As I have said, it is a timing (duty cycle) problem. If you move CVR2 to the new position then it will read what is coming from C1 "only".

As you increase the duty cycle, C1 will not be able to supply enough current, the voltage will drop and more will be taken direct from the source to charge the coil.
The new position of CVR2 will be able to measure what goes in and out of C1, and as you change the duty you will see the difference.

Going back to my first post, what was interesting for me was the L1 and magnet (they do not charge C1), they charge C2. C2 can't be charged directly from the source as you have it wired. So all the charge in C2 comes from the coil and magnet setup.

What seems to be happening is that the PM field is being compressed, and then released, which then generates a current greater than what was used to compress the field in the first place by the coil, hence my reference to spring, compress and release. But here the release is two fold, the coil + the added field change of the magnet on the coil.

Now you need to measure all the energy to the load (LED)

Regards

Mike 8)

Where you have placed CVR2 Mike,means that both CVRs will have current flowing through them during both the off and on time of the transistor
CVR1 will show a DC current flow,and CVR2 will show an alternating current flow.
 I want to see the current flow in from the source,and the current flow from the cap and source during the on time seperately.


Brad


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I made a quick replication of Tinman his magnet/coil setup in order to take some measurements.

Using a 2.7mH / 2.6 Ohm coil i had laying around.

Screenshot shows:

yellow: battery voltage (12.35V, not shown due to scopes limitation of 4 measurement points only).
Purple: CSR1 (10 ohm) signal 15.68mA mean
Red:    math function (yellow x purple) 189.2mW input mean.

Blue:   CSR2 signal
green: current probe signal in C1 minus lead.

Video also shows input power calculated by using DMM's for voltage and current (196mW).

Video here:  https://www.youtube.com/watch?v=xTDG_xs8FNU


Itsu

Hi Itsu

Thanks for taking the time to experiment with this.

May i ask if you put the steel sleve inside the coil as well?.

You seem to have the same current flow values across both CVRs ?
That seems to be different to my results.
As you can see in my last video,where i swap out the CVRs for small DC motors with parallel caps,the one in CVR 2 position starts running well before the one in CVR1s position--why would that be?.

In the previous video to that,i show the temperature of each CVR,where CVR2s temperature is some 4 to 5 degrees C hotter--why would that be?

I will carry out the math test using average tonight,and see what happens.


Brad


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Thanks for the files Jim.
Can confirm the rotor file is editable, when logged in :)

No worries, Just realised I can't make these individual components editable in a export because they're using tinkercad scripting. duh!

As axles etc will vary depending on what people have access to, I'm thinking we need a better option for those that don't use Tinkercad. Otherwise it will be a pain the bum to resize for what you have at hand.
   

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As you can see in my last video,where i swap out the CVRs for small DC motors with parallel caps,the one in CVR 2 position starts running well before the one in CVR1s position--why would that be?.

In the previous video to that,i show the temperature of each CVR,where CVR2s temperature is some 4 to 5 degrees C hotter--why would that be?


Hey brad

I see it like this.... CVR1 never sees a lot of current. Mostly due to very little voltage ever across cvr1. Once C1 nearly equals the source, then its source minus C1 equals Vcvr1. Cvr2 on the other hand gets to see higher voltages.  Cvr1 never sees anything higher than source minus C1 voltage thus not enough voltage to get the motor turning, even as you increase the on time and cvr2 turns faster, cvr1 and its cap never really sees any spikes, etc, like cvr2.  Thinkin what effect a larger or smaller cap on motor 2.
 Heck, consider the average currents in cvr1 and how much heat is dissipated, and now imagine the heat generated by the spikes of current in cvr2. cvr1 never gets those inrushes of current and has not chance of cvr heat potentials. Maybe use smaller value resistors. Just the mention of the heat from them alone is too much energy not getting to the coil. :) Especially if those losses could be wasting some of the rainbow. ;)

Mags

So your C1 is a good isolator. Try smaller caps for C1? 
   

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One more thing..  Try to measure the voltage and possibly note the brightness of the led and try the circuit without cvrs in the circuit to see the possible loss happening in that hot resistor. So if we have a low loss resistor for a cvr1 and measure the output of the circuit(cap and led), and we can see very insignificant losses, well then thats a nice band in the rainbow. ;)



Mags
   

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Hi Itsu

Thanks for taking the time to experiment with this.

May i ask if you put the steel sleve inside the coil as well?.

You seem to have the same current flow values across both CVRs ?
That seems to be different to my results.
As you can see in my last video,where i swap out the CVRs for small DC motors with parallel caps,the one in CVR 2 position starts running well before the one in CVR1s position--why would that be?.

In the previous video to that,i show the temperature of each CVR,where CVR2s temperature is some 4 to 5 degrees C hotter--why would that be?

I will carry out the math test using average tonight,and see what happens.


Brad


Brad,

Quote
May i ask if you put the steel sleve inside the coil as well?.

sorry, i do not have any steel sleeved coil, just this normal coil.


Quote
You seem to have the same current flow values across both CVRs ?

No, see screenshot below, there is 4x more current (rms) flowing through CSR2 (70mA) compared to csr1 (18mA).


Quote
As you can see in my last video,where i swap out the CVRs for small DC motors with parallel caps,the one in CVR 2 position starts running well before the one in CVR1s position--why would that be?.

Because there is (like you said) more current flowing through the csr2 position.


Quote
In the previous video to that,i show the temperature of each CVR,where CVR2s temperature is some 4 to 5 degrees C hotter--why would that be?

Because of the higher current through csr2  (mine has 0.3°C higher temp., but these are 20W csr's).

Itsu
   

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If we calculate the power dissipated by the both csr's we get:

P=U²/R

Pcsr1= 0.185²/10 = 3.4mW
Pcsr2= 0.778²/10 = 60.5mW

Itsu
   

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Brad,

No, see screenshot below, there is 4x more current (rms) flowing through CSR2 (70mA) compared to csr1 (18mA).


Ok
So if the voltage is a constant,then the power is calculated using that constant voltage value by the current.
So if more current is flowing through CVR2,then more power is being delivered to the coil from C1 than the power supply is delivering to the circuit--correct?.


Brad


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Thought experiment.

I have removed the inductor from the circuit
Should we still get the same results,where more current passes through CVR 2 than that of CVR1,or will both CVRs have the same value of current flowing through them ?.


Brad


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Ok
So if the voltage is a constant,then the power is calculated using that constant voltage value by the current.
So if more current is flowing through CVR2,then more power is being delivered to the coil from C1 than the power supply is delivering to the circuit--correct?.


Brad

Yes, at first glance that seem to be correct,   however i think it has something to do like Centraflow mentioned
in his post #124, that C1 is fully charged to 12V at the start and being maintained to be fully charged by the
battery while the transistor only at 5% duty cycle pulls power from this C1.

Itsu
   

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Thought experiment.

I have removed the inductor from the circuit
Should we still get the same results,where more current passes through CVR 2 than that of CVR1,or will both CVRs have the same value of current flowing through them ?.


Brad

No, no more current flows as we have no more 12V on the Collector (i cheated as i tried it).

Itsu
   

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Yes, at first glance that seem to be correct,   however i think it has something to do like Centraflow mentioned
in his post #124, that C1 is fully charged to 12V at the start and being maintained to be fully charged by the
battery while the transistor only at 5% duty cycle pulls power from this C1.

Itsu

But the average current through CVR1 still should be the same as the average current through CVR2,as a capacitor is not an energy source.

When the voltage is a constant,then the same amount of current has to flow into the cap (CVR1)as what flows out of the cap (CVR2).

Here are the test results from having the scope math give us the average power,instead of the RMS power.

First scope shot is P/in from the power supply--CH2 across CVR1.
Second scope shot is CH2 acoss CVR2.


Brad


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No, no more current flows as we have no more 12V on the Collector (i cheated as i tried it).

Itsu

Ah yes,my mistake.

Retry

How about in the below circuit?.


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But the average current through CVR1 still should be the same as the average current through CVR2,as a capacitor is not an energy source.

When the voltage is a constant,then the same amount of current has to flow into the cap (CVR1)as what flows out of the cap (CVR2).

Here are the test results from having the scope math give us the average power,instead of the RMS power.

First scope shot is P/in from the power supply--CH2 across CVR1.
Second scope shot is CH2 acoss CVR2.


Brad



Brad,

i agree with you there, but obviously this cannot be true, so another explaination must be found.



Thanks for the screenshots, it shows you now are running at 24V.

It also shows in screenshot 1 that your input power according to the Math trace is 1.09W average.
This is confirmed by calculating the 24.1V x 46mA  = 1.1W.



No comment on screenshot 2 as i am not sure how to interpret that data, as we might be comparing apples with pears.


Itsu   
   

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I also took a couple of scope shots of just the current traces,as the voltage is a constant.

Scope shot one across CVR1
Scope shot 2 across CVR2
Both show RMS and average values.


Brad


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Hi Brad,

Do you plan to remove the permanent magnet from the coil so that you are left with the iron sleeve as the core? I believe that would be a step forward to find out where the 'extra' the measurements show comes from.



Thanks for sharing.
Gyula

Hi Gyula.

I tried to get the magnets out,but seems i glued them a bit better than i thought,as they will not come out without breaking them or the coil former.

I will make one the same,but leave out the magnets this time,and see how we go.

I did try another coil,and CVR had a very slightly higher current value,but were talking only about 4 mV difference.
So nothing like the results we are getting with the magnet core coil.


Brad.


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Ah yes,my mistake.

Retry

How about in the below circuit?.

Same story there,  still no 12V on the collector.

Itsu
   

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Same story there,  still no 12V on the collector.

Itsu

I am not sure what 12v on the collector has to do with it,as when the transistor closes,current will flow through the circuit via the LED(now up the right way),and the capacitor.

But anyway,how about this circuit?


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Brad,

i agree with you there, but obviously this cannot be true, so another explaination must be found.


Itsu   

That is what we are told.

It is odd that no matter what i do,whether i use the scope to show that CVR2 has a higher current flowing through it than CVR1,or i show CVR2 having a higher temperature than CVR1,or i use two identical DC motor/cap combo's in place of CVR 1&2,and show that the motor/cap combo in the CVR2 position start spinning up way before that of the motor/cap combo in the CVR1 position-->or even you your self see it in your own test setup,that what we are told/taught should be the case,seems to trump all bench tests that show the opposite.

I do have a theory about why we are seeing what we are seeing,but i have a feeling that it will only fall on deaf ears.

Anyway,thanks for taking the time to run the test  O0


Brad.


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@Jim
   Found the rotor coil .stl on thingiverse but not the rotor. Do not need to edit as I can use any axle size you set. Chance you can upload to there as well?
New printer here next week and spools of #20 and #22 available. Magnets here local to me.
thay
   
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Hi Gyula.

I tried to get the magnets out,but seems i glued them a bit better than i thought,as they will not come out without breaking them or the coil former.

I will make one the same,but leave out the magnets this time,and see how we go.

I did try another coil,and CVR had a very slightly higher current value,but were talking only about 4 mV difference.
So nothing like the results we are getting with the magnet core coil.


Brad.

Hi Brad,

Thanks for trying the no magnet core in the sleeve coil too. Hopefully you can find a sleeve from the same iron material you use in the first coil, I believe the iron may also have an influence on the results.

Re on your modified (coil removed) drawing shown in Reply #141: Itsu probably meant diode D1 in series with the collector, for it still has a reverse connection and block any collector current as the LED did before you flipped it.

But now that you completely left out both diodes from the collector circuit and show only a resistor (Reply #146), does the circuit still show higher average current across CVR2 versus CVR1?  As per conventional theory, the voltage drop across CVR1 should be higher than across CVR2 because the voltage drop across it should increase whenever capacitor C1 is (slightly) recharged from the 12V source to make up for the  the transistor current that takes out charge first of all from C1.  MAybe I am wrong with this.

Gyula
   
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