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Author Topic: LTJT - poynt99 Tests #2  (Read 82626 times)
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Quote
.99:

Indeed I can use a 1 Ohm in the emitter to see what power our transistor is dissipating. I'll try this when I get to testing the circuit again, today or tomorrow.

Good. Call it CSR3.  I have added this to my circuit and checked it briefly using my DSO at home.  The power dissipated in this emitter 1-ohm resistor CSR3 is not negligible and should be included -- increasing n a small amount.  My circuit now appears much like your schematic, except I've added CSR3.

 
Quote
.99  Pitotal and Pcsr1 must be added together to obtain Pvbat.

I do not concede this point -- still awaiting data on what happens to Pin, Pout and n (COP) when a 1/2 ohm CSR1 is used instead of a 1 ohm resistor.  I prefer data to theoretical discussions and I'm guided by the data.
 In any case, as I've noted, as long as CSR1 is small (like 1/2 ohm), it matters little to the COP whether one adds or subtracts Pcsr1.

I have also observed an interesting change in the power waveform (across CSR1) when the voltage from my power supply (rather than battery) is decreased, down from 1.5V to about 0.6 V when the LED goes out.  At about 1.1 volt (in my circuit, may vary with details of the toroid etc), the power curve goes from entirely positive to sometimes positive and sometimes negative.  That is, the curve crosses the zero line and the waveform becomes more erratic (many more wiggles) as the voltage is decreased to about 1 volt.  Clearly, the phase relationship between current and voltage changes, which I find interesting and perhaps significant.

It would be nice to have two oscilloscopes with math and also mean calculation on the math product (power)...   Perhaps someday. ;)



« Last Edit: 2011-03-01, 16:46:37 by PhysicsProf »
   
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I've been working with the circuit further.  I find that the current flows through CSR3 then through CSR2, alternately -- they are both outputs yet they are out of phase (my DSO shows).  Therefore, I connected the output of the emitter directly to the point labeled "p22t" (also "v4") in .99's latest circuit schematic.  It makes some sense to measure the output current therefore in CSR2 alone, and CSR3 is not needed.  Does this make sense?  

CSR1 then gives the input current while CSR2 gives the output current (flowing from both the collector and the emitter), keeping things simplified.

A question for you, .99.  In your latest circuit LTJT2 - schema02, you do not show any connection to ground -- which is a change from schema01.  Why the change?
   
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  Hope you're finding interesting results in the lab, .99.   O0   A couple more questions in the interim:

  I've gone back through the thread trying to find details on your toroid and the windings you used...  missed it somehow.
Can you repeat a few details on the toroid used and bifilar windings?  size of wire, etc. -- for the ferrite-core toroid.  
Did you measure the inductance for each winding?  which I presume are close to the same.
 (Or if someone has the data, please re-post them... )
   
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This is my first post here and it is this thread that has got me here. I have some idea to share with you guys concerning the measurement. Please let me borrow the schematic attached to Reply #124 of this thread.

As professor already pointed out, csr1 and csr2 gives the input and output currents, very nice step of simplification (in math: Ibat = Icsr1 = V2, Iled = Icsr2 = V4, see attached schematic for definition of V).  O0

And it is also great that .99 argued for Pbat = Pitotal + Pcsr1. I fully agree with him. Here is why: Pitotal = V2*V1, Pbat = Ibat * (V1-V2), Pcsr1 = Icsr1 * (0 - V2) = - Iscr1*V2 {note: V2 < 0}. Since Ibat = Icsr1 = Vcsr1, we got Pbat = Ibat*V1 - Ibat*V2 = Pitotal + Pcsr1.

However, the above relationship holds only if Rcsr1 = Rcsr2 = 1 ohm, but we all know such idea could never happen in real life. Therefore we must take the real values of Rcsr1 and Rcsr2 into the equation. By the Ohm's Law: V2 = - Icsr1 * Rcsr1, V4 = Icsr2 * Rcsr2. Take note that the currents Icsr1 and Icsr2 are not the same in quantity in general.

Therefore, Pbat = Pitotal + Pcsr1 = (|V2|/Rcsr1) * V1 + (|V2|/Rcsr1) * |V2| = (|V2|*V1+|V2|*|V2|) / Rcsr1 = Pbat_nominal / Rcsr1.

Here Pbat_nominal = |V2|*V1+|V2|*|V2|, which is what we have calculated assuming Rcsr1  = 1.

Similarly, Pled = Pled_nominal / Rcsr2.

And so, n = n_nominal * (Rcsr1/Rcsr2), where n_nominal  = Pled_nominal / Pbat_nominal.

To obtain the real n, it seems that we also need to know (Rcsr1/Rcsr2). But a clever experiment design can help us find the real n without knowing the ratio: just repeat the experiments with the two resisters Rcsr1 and Rcsr2 swapped, and obtain n'_nominal. Now assume that by swapping, the real n does not change much. Then we have:

 n = n_nominal * (Rcsr1/Rcsr2) and  n = n'_nominal * (Rcsr2/Rcsr1).

Therefore, n*n = n_nominal * n'_nominal and n = sqrt(n_nominal * n'_nominal).

Note that the assumption of n being the same after swapping is based on the idea that Rcsr1 and Rcsr2 are insignificant components in the circuit and they are close in value.

Hopefully this rather long ranting can add something to our methodology.

lanenal
   
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Basically, in my first post I proposed a method of more accurate measurement: just measure twice with the Rcsr1 and Rcsr2 swapped, then find the square root of the product of the two nominal n.

In the second post, I would like to propose a simplified efficiency calculation.

First of all, we group the components into three parts:

1. The bat and the Rcsr1 is grouped into the Power Source part. The idea is to view csr1 as an internal resistor of the Big-Bat.

2. The Led and the Rcsr2 is grouped into the Power Sink part. They both consume the energy from the coil.

3. The rest is grouped as the Joule Thief system. And it is the efficiency of this system that we should measure.

With that partition, the new COP measurement should be n = Pototal/Pitotal.

Note: Pototal = V3*V4, Pitotal=V1*V2, according to the schematics in my first post.
Note: I am using instantaneous measurements here (power, not the work), but it is clear that the results carries over to work as well, which is power integrated over time.

The same methodology proposed in my first post applies readily to the new measurement.

lanenal

P.S.: with this new n definition, .99's measurement will be 1.06 > 1. But since that's only a nominal measurement, and we don't know the ratio Rcsr1/Rcsr2, therefore the real n can't be determined yet. It could be less than 1, if the R values have +- 5% of error.
« Last Edit: 2011-03-03, 00:57:16 by lanenal »
   

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It's not as complicated as it may seem...
 

I've been working with the circuit further.  I find that the current flows through CSR3 then through CSR2, alternately -- they are both outputs yet they are out of phase (my DSO shows).  Therefore, I connected the output of the emitter directly to the point labeled "p22t" (also "v4") in .99's latest circuit schematic.  It makes some sense to measure the output current therefore in CSR2 alone, and CSR3 is not needed.  Does this make sense?  
This may work in this case, but I would not recommend this practice. The purist and most scientific approach is to have a series CSR for every source and sink of power we are interested in getting a power measurement on. I would suggest we restrict our power measurements to INPUT, and the LED/CSR2 combination for the output. The LED (and it's associated CSR2) is the only real load in this circuit. The goal is to get as much of the used battery power transferred to the LED as possible. In theory, power in equals all dissipated power out. Our goal is to shift as much of that outpu power to the LED as we can. When you add up all the dissipations, of course they will add up to the battery power. We want to bias the distribution of power mostly to the LED.

So while it is useful to know how much power the transistor is eating up, it does not factor into the efficiency equation. Only the power source and the intended load factor into that.

Quote
CSR1 then gives the input current while CSR2 gives the output current (flowing from both the collector and the emitter), keeping things simplified.
Sometimes simplifications can cause us to overlook important things.

Quote
A question for you, .99.  In your latest circuit LTJT2 - schema02, you do not show any connection to ground -- which is a change from schema01.  Why the change?
As I said in my post, the ground symbols just add confusion to the matter when a grounded CSR for the battery is employed. I had hoped that re-drawing the circuit without the ground symbols would make things clearer...have I failed?

"Ground" is just a reference point. The probe reference points are still denoted on the schematic. Electrically, the two versions of the schematic are identical.

.99
   

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It's not as complicated as it may seem...
 Hope you're finding interesting results in the lab, .99.   O0   A couple more questions in the interim:

  I've gone back through the thread trying to find details on your toroid and the windings you used...  missed it somehow.
Can you repeat a few details on the toroid used and bifilar windings?  size of wire, etc. -- for the ferrite-core toroid.  
Did you measure the inductance for each winding?  which I presume are close to the same.
 (Or if someone has the data, please re-post them... )

Here is a link to a post with some info on the cores.
http://www.overunityresearch.com/index.php?topic=717.msg10617#msg10617

Here is a link to the notes scan I mentioned in that post:
http://www.overunityresearch.com/index.php?action=dlattach;topic=717.0;attach=3603

Note that I physically cut the core I had, in order to decrease the core permeability and increase the frequency of operation. I made the inductance measurements BEFORE I cut it which of course changes all the parameters. But all the wire and turns information is there in my notes.

.99
   

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It's not as complicated as it may seem...
Basically, in my first post I proposed a method of more accurate measurement: just measure twice with the Rcsr1 and Rcsr2 swapped, then find the square root of the product of the two nominal n.

In the second post, I would like to propose a simplified efficiency calculation.

First of all, we group the components into three parts:

1. The bat and the Rcsr1 is grouped into the Power Source part. The idea is to view csr1 as an internal resistor of the Big-Bat.

2. The Led and the Rcsr2 is grouped into the Power Sink part. They both consume the energy from the coil.

3. The rest is grouped as the Joule Thief system. And it is the efficiency of this system that we should measure.

With that partition, the new COP measurement should be n = Pototal/Pitotal.

Note: Pototal = V3*V4, Pitotal=V1*V2, according to the schematics in my first post.
Note: I am using instantaneous measurements here (power, not the work), but it is clear that the results carries over to work as well, which is power integrated over time.

The same methodology proposed in my first post applies readily to the new measurement.

lanenal

P.S.: with this new n definition, .99's measurement will be 1.06 > 1. But since that's only a nominal measurement, and we don't know the ratio Rcsr1/Rcsr2, therefore the real n can't be determined yet. It could be less than 1, if the R values have +- 5% of error.

I think I agree with you here, if I understand correctly. However, as I pointed out above, I would not recommend that the transistor emitter be included in the Pototal calculation.

Also, I think it will be far easier to calibrate, i.e. tweak our resistors to be 1.00 Ohms rather than going through many complicated calculations. If we can make or buy very accurate 1 Ohm resistors, we are better off imo.

.99
   
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Welcome, Lanenal, and thanks for your comments.  

I have inserted a 1-ohm resistor in the emitter path and found the results interesting.  [What I posted a bit earlier has been corrected at this point, in the following post.]


.99
Quote
Also, I think it will be far easier to calibrate, i.e. tweak our resistors to be 1.00 Ohms rather than going through many complicated calculations. If we can make or buy very accurate 1 Ohm resistors, we are better off imo.]

I agree with that, but I've asked and hope you will provide us with data from your JT circuit when CSR1 at 1 ohm is replaced with a 1/2 ohm resistor, as I think you said you would do.

Note that in your circuit, you now have the collector path going through the LED and CSR2 AND through CSR1, back to the battery negative, and we'll be watching that you take this into consideration.   Having looked at the oscilloscope output the way you have it connected, .99, I see that P-CSR1 is NEGATIVE on the scope -- I think this is what you were trying to say.  Having seen the data, I understand now.  That is, with CSR1 before the battery, then the absolute value of P-cSR1 needs to be added to determine the total Pinput.  

By the same token, the current flow from the collector is such that the power from its current flowing through CRS1 must be added to the total output power.  Correct me if I'm wrong.
\
 All of this becomes simpler and less prone to error, IMO, when CSR1 is reduced to 1/2 ohm or even less (as long as the current is still measurable with acceptable accuracy), since the power dissipated in CSR1 becomes relatively small

Thanks for providing some details about the windings on your toroid, and how you cut it.
  
.99 wrote:

Quote
When you add up all the dissipations, of course they will add up to the battery power.

I detect a certain bias here that is disconcerting.  We are trying to determine EXPERIMENTALLY whether or not a simple system can demonstrate overunity, more power out than in.   It is not a foregone conclusion that "When you add up all the dissipations, of course they will add up to the battery power. "    That is what we are in process of determining, experimentally.  Not by pre-determined conclusion without the need for experiments ("Ipse dixit"  authoritarian style).


« Last Edit: 2011-03-03, 06:57:12 by PhysicsProf »
   
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I detect a certain bias here that is disconcerting.  We are trying to determine EXPERIMENTALLY whether or not a simple system can demonstrate overunity, more power out than in.

The bias that disconcerting is your bias PhysicsProf.  Yes you are trying to determine experimentally if a simple system can demonstrate over unity, but that shouldn't mean that you should go into the experiment with an expectation that you will measure over unity.  That is what you are implying when you take issue with Poynt's statement that says, "When you add up all the dissipations, of course they will add up to the battery power."

It would be totally unscientific on your part and unreasonably biased to expect measurements that show over unity.

There is nothing wrong with being open minded but there are limits.  It makes no sense to use inverse logic with respect to the conservation of energy.

MileHigh
« Last Edit: 2011-03-03, 08:56:44 by MileHigh »
   
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This may work in this case, but I would not recommend this practice. The purist and most scientific approach is to have a series CSR for every source and sink of power we are interested in getting a power measurement on. I would suggest we restrict our power measurements to INPUT, and the LED/CSR2 combination for the output. The LED (and it's associated CSR2) is the only real load in this circuit. The goal is to get as much of the used battery power transferred to the LED as possible. In theory, power in equals all dissipated power out. Our goal is to shift as much of that outpu power to the LED as we can. When you add up all the dissipations, of course they will add up to the battery power. We want to bias the distribution of power mostly to the LED.

So while it is useful to know how much power the transistor is eating up, it does not factor into the efficiency equation. Only the power source and the intended load factor into that.
[snip]
.99

"Intended" by whom?

I have come back to this point because I think it is significant in our understanding and in our calculation of efficiency.

Let us consider the JT system as a "black box", that may or may not have more power out than power in.  That is what we are trying to find out empirically.

We look at the current going into our "black box" as well as what comes out -- and the question here is -- what power is coming out?   There are two currents coming out of the toroid/transistor combination which constitutes the black box -- one from the collector and the other FROM the emitter -- and both go from the black box to ground.  Both can do useful work, such as heating a resistor.  This output heat (from both paths) is not just for convenience in measuring -- it is OUTPUT POWER.  

Yes, the original system has just one LED, connected to the collector.  But why could we not hook a light to the output from the emitter also?-- the fact is, we could.  It turns out that the voltage from the emitter is probably not high enough to light an LED (although I may try it), but some other form of bulb should work -- and in any case, we can certainly extract heat before the current is dumped to the ground connection simply by inserting a heating element called a resistor in the path from emitter to ground.

There is only ONE current coming out of the battery (or power supply) -- and for this we calculate the associated INPUT power, Pin.
There are TWO currents coming out of the black-box, and these must both be accounted for (not ignored) to accurately calculate the OUTPUT power, Pout.

I note that lanenal agreed, and ask if you also agree (dear reader, including .99) -- and if not, specifically why not?    Just saying that original circuit by Lawrence or someone else did not have a heat or light-producing element in the path from emitter to ground is not a good reason to ignore this portion of the power emerging from the system.
   

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It's not as complicated as it may seem...
Welcome, Lanenal, and thanks for your comments.  

I have inserted a 1-ohm resistor in the emitter path and found the results interesting.  [What I posted a bit earlier has been corrected at this point, in the following post.]


.99
I agree with that, but I've asked and hope you will provide us with data from your JT circuit when CSR1 at 1 ohm is replaced with a 1/2 ohm resistor, as I think you said you would do.
Yes, I will do that.

Quote
Note that in your circuit, you now have the collector path going through the LED and CSR2 AND through CSR1, back to the battery negative, and we'll be watching that you take this into consideration.
Yes, CSR1 should be considered as a load as I have mentioned. We will add it's power to the LED and CSR2 power.

Quote
By the same token, the current flow from the collector is such that the power from its current flowing through CRS1 must be added to the total output power.  Correct me if I'm wrong.
Yes, we will consider CSR1 as an output dissipator of power.

Quote
All of this becomes simpler and less prone to error, IMO, when CSR1 is reduced to 1/2 ohm or even less (as long as the current is still measurable with acceptable accuracy), since the power dissipated in CSR1 becomes relatively small.
Agreed.

Quote
I detect a certain bias here that is disconcerting.  We are trying to determine EXPERIMENTALLY whether or not a simple system can demonstrate overunity, more power out than in.   It is not a foregone conclusion that "When you add up all the dissipations, of course they will add up to the battery power. "    That is what we are in process of determining, experimentally.  Not by pre-determined conclusion without the need for experiments ("Ipse dixit"  authoritarian style).
I did precede that sentence with this one: "In theory, power in equals all dissipated power out." Perhaps you might allow me some latitude in regards to being "jumpy" in response to anything that might suggest discussions about theory of operation and theoretical efficiencies. Thanks.

I am just as curious as to the unusually-high efficiency as anyone, which is why I'm going to re-do the tests and include the transistor dissipation and add CSR1 to the output power as well as CSR3. After that, the only remaining power dissipations are in the battery itself, the two coils, Rb, and the core. I do not know how to measure the core dissipation directly though, so we may have to forgo that one.

.99
   
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[quote ]
 remaining power dissipations are in the battery itself

[/quote]

ehehe... kcits htiw POC
   
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@.99

Quote
Also, I think it will be far easier to calibrate, i.e. tweak our resistors to be 1.00 Ohms rather than going through many complicated calculations. If we can make or buy very accurate 1 Ohm resistors, we are better off imo.

Or if we can measure both Rcsr1 and Rcsr2 accurately, then n_real = n_nominal * (Rcsr1/Rcsr2), which should be easy enough.

@PhysicsProf

I have not really considered the emitter question carefully, yet it is undoubtedly a very interesting topic. It seems to me, a cycle in a basic JT circuit, has two phases:

phase 1. the energizing phase: the transistor is in the ON state and the current in the coil connected to the collector is increasing.

phase 2. the vanquishing phase: the transistor is in the OFF, and the the current in that same coil is going through the  LED.

It seems to me that phase 1 is a pure input phase, and there is no active output (ignoring the wasted power in the transistor, the 1k transistor, and the coils). Then in phase 2, the battery AND the coil connected to the collector are powering the LED.

If the analysis above is fine, I tend to ignore the emitter output, not if we can have easier and more accurate measurements.

However, it is possible to calculate that output without inserting a third measuring transistor between the ground and the emitter. In fact, we should remove CSR2 and have the LED directly connect to the ground, then the new Pototal can be found by integrate [V3*V2] over time, and this time the Pototal includes the output energy spent on both the LED and the transistor. Moreover, this time the current is estimated by V2 on one single CSR1, so value errors in CSR1 won't be a factor anymore, the calculated n would be EXACT!!!

Thus, I would say yes for the sake of simplicity! Here is the proposed method:

1. take CSR2 out and connect the LED directly to the ground (or just leave as is and don't measure V4, measure V2 instead if you were using two scopes).

2. measure V1, V2, V3 as before.

3. calculate Pitotal by MEAN [V1*V2], which gives the time average input power.

4. calculate Pototal by MEAN [V3*V2] over time, similar to finding the Pitotal.

5. then n = Potatal/Pitotal, which is EXACT as the error in the value of CSR1 is balanced out in the way n is calculated.  O0

This seems to be as simple as it can be. Also, it only leaves tiny energy leaks out of consideration, namely the leaks in the 1k resistor and the coils.

cheers,

lanenal
« Last Edit: 2011-03-03, 15:59:27 by lanenal »
   
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Yes, I will do that.
Yes, CSR1 should be considered as a load as I have mentioned. We will add it's power to the LED and CSR2 power.
Yes, we will consider CSR1 as an output dissipator of power.
Agreed.
I did precede that sentence with this one: "In theory, power in equals all dissipated power out." Perhaps you might allow me some latitude in regards to being "jumpy" in response to anything that might suggest discussions about theory of operation and theoretical efficiencies. Thanks.
 
I am just as curious as to the unusually-high efficiency as anyone, which is why I'm going to re-do the tests and include the transistor dissipation and add CSR1 to the output power as well as CSR3. After that, the only remaining power dissipations are in the battery itself, the two coils, Rb, and the core. I do not know how to measure the core dissipation directly though, so we may have to forgo that one.

.99

Thank you for your responses, .99.  Glad to see that you are also "curious as to the unusually-high efficiency"    We are remarkably in agreement at this point, and I'd like to emphasize your point:
Quote
I'm going to re-do the tests and include the transistor dissipation and add CSR1 to the output power as well as CSR3
.

I am looking forward to your measurements.  

On my side, I measured the inductance of the 1" yellow toroid (from Jameco) that I wound bifilar that gives the better results -- both of my windings have L = 24 uH.

@laneal -- I'm puzzling over your post and will do some measurements using your method...  thanks.  
   
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[snip]
@PhysicsProf

[snip]

However, it is possible to calculate that output without inserting a third measuring transistor between the ground and the emitter. In fact, we should remove CSR2 and have the LED directly connect to the ground, then the new Pototal can be found by integrate [V3*V2] over time, and this time the Pototal includes the output energy spent on both the LED and the transistor. Moreover, this time the current is estimated by V2 on one single CSR1, so value errors in CSR1 won't be a factor anymore, the calculated n would be EXACT!!!

Thus, I would say yes for the sake of simplicity! Here is the proposed method:

1. take CSR2 out and connect the LED directly to the ground (or just leave as is and don't measure V4, measure V2 instead if you were using two scopes).

2. measure V1, V2, V3 as before.

3. calculate Pitotal by MEAN [V1*V2], which gives the time average input power.

4. calculate Pototal by MEAN [V3*V2] over time, similar to finding the Pitotal.

5. then n = Potatal/Pitotal, which is EXACT as the error in the value of CSR1 is balanced out in the way n is calculated.  O0

This seems to be as simple as it can be. Also, it only leaves tiny energy leaks out of consideration, namely the leaks in the 1k resistor and the coils.

cheers,

lanenal

OK -- I see what you're doing and I like it!  CSR1 is used as a current-measuring resistor for both the input and output legs of the circuit.  As your wrote, and I wish to emphasize:

In fact, we should remove CSR2 and have the LED directly connect to the ground, then the new Pototal can be found by integrate [V3*V2] over time, and this time the Pototal includes the output energy spent on both the LED and the transistor. Moreover, this time the current is estimated by V2 on one single CSR1, so value errors in CSR1 won't be a factor anymore, the calculated n would be EXACT!!!


Looks great to me -- I wonder if others agree, particularly .99 and humbugger.    Any problems seen?

You have, I think, homed in on a simple yet elegant solution to measuring Pin, Pout, and n.
   

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It's not as complicated as it may seem...
lanenal,

I tried your method in PSpice, and it comes very close to the actual summed power in the transistor and LED, but it is lower by about 1.5%. I can not account for that loss at the moment, but it would be handy to have only the one CSR in the circuit.

One other potential problem in combining all the output powers, is we are less likely able to identify where or which device is causing our efficiency to be so high.

At any rate, I'll leave it up to you and the professor to decide which method you want to use.

.99
   
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lanenal,

I tried your method in PSpice, and it comes very close to the actual summed power in the transistor and LED, but it is lower by about 1.5%. I can not account for that loss at the moment, but it would be handy to have only the one CSR in the circuit.

One other potential problem in combining all the output powers, is we are less likely able to identify where or which device is causing our efficiency to be so high.

At any rate, I'll leave it up to you and the professor to decide which method you want to use.

.99


  Great idea, Lanenal -- elegant.   Thanks for checking this, .99. 
I have done some tests now with Lanenal's method and I love the simplicity of it.  The channel 2 probe stays put on CSR1, as do probe-ground leads.  It is quick to move the channel 1 probe between the 2 points, for input and output. 

So, I have done tests using my "best" toroid, one which I wound myself and call J1.  It has looked the best using .99's circuit.   I also extracted the small transformer from a Fuji AA flash throw0awat camera and wired that into the circuit for another test.

I'm using my ATTEN 1062 DSO, which has a MATH function and shows the Power waveform in green Using L's method, I plot the Pin and Pout and then I can straightforwardly compare the AREA under the waveform for one cycle, which gives me

Eout/Ein = Pout/Pin (since for the same time period, one cycle) = n.

Using L's method, I don't have to subtract or add P-csr1, which is great, I can simply calculate the areas under the Power curves (as a function of time, so this yields Energy) for In and Output, and Divide Eout/Ein to get n.
I have done this for toroid J1 and the Fuji transformer.  The results --

Toroid J1:  n = 1.4
Fuji transformer:  n = 1.08

CAVEAT:  Both results are approximate, given that I have done the area calculations by hand.  I may put the CSV data from the DSO into Excel and see if I can refine the calculation; or go up to the University and use the Tek 3032 which calculates the Math Mean directly (giving Pmean with hardly any work) --  applied to the same circuit.

I will post photos of the set-ups soon...  I haven't been able to extract the waveforms in a screen-shot; wish i could to show you directly.  For J1, the area under Pout appears larger than the area under Pin, by eye.  (Have I done something wrong, or is this something to cheer about?  not real sure yet.)

The circuit is rather easy to put together on a circuit-board, and I encourage others to participate and check my and .99's results.
   
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Well done guys!   The research and the collaboration in this thread has been really really impressive -- especially if the result of COP>1 can be replicated.       I will attempt my own replication in the next few weeks -- I'm moving my scope out of storage and into my office this weekend.

Lanenal , your ideas for power measurement were robust and brilliant. 

PhysicsProf, thanks for taking the time to organize this and do all the hard work required to do the measurements.   I know this is not easy, but you've gone ahead with it despite the criticism of some unnamed users on another boards , whose real purpose appears to discourage research rather than have open debate.  I've built Joule Thief too and was mystified by the circuit.   Measuring power on it is non-trivial question.   

Poynt99, thanks for providing the board ,and providing the schematics and intellectual support for this research.

Let's let these COP>1 measurements keep us motivated to pursue multiple avenues of research in order to achieve what we all know is possible.  In the meantime, we need to make sure that the methodology for Joule Thief power measurement is valid and will stand up to scrutiny --  but these results are very encouraging.   Wikipedia knows nothing when it comes to suppressed knowledge.  Wikipedia could get away with telling us the Romans invented the first 365-day solar calendar , unless people question the 'authorized' 'official' knowledge propagated by large institutional hierarchies.

Anyway great job guys, I'm very impressed with the research in this thread.
   
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Thanks for the encouraging words, feynman.

More measurements and care, and I think the n=1.4 number is high.  I have also concluded that my "area under the power curve" method, by hand, is a bit too crude to be reliable for numbers close to unity.
 I plan a trip to the 3032 at the University as soon as I can get there -- and I look forward to .99's measurements.
   
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Here's what Wikipedia says about Joule Thief in terms of waveforms:

   
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Good job guys, and thanks for sharing your results.

Quote from: poynt99
I tried your method in PSpice, and it comes very close to the actual summed power in the transistor and LED, but it is lower by about 1.5%.

It is certainly good to know that the measured Pototal is LOWER than the actual. I'd like to do an analysis to show that it is indeed the case IF we also include the power spent on the 1k resistor (our measuring method unchanged).

Pototal = P1k + Pbe + Pce + Pled.

P1k = power on the 1k resistor = I1k * V1k,
Pbe = power on the be knot of the transistor = Ibe * Vbe,
Pce = power on the ce knot of the transistor = Ice * Vbe,
Pled = power on the LED = Iled*Vled.

On the input side it is relatively simple:
Iin = Icsr1 = Ibat, Vin = Vbat - Vcsr1, so Pitotal = Iin*Vin = Icsr1 * V1
The measurement is exact (Note: Vin=V1, Iin=Icsr1=Vcsr1=V2, with Rcsr1=1).

So I will concentrate on the analysis of the output side, and consider the ON and OFF state of the transistor separately.

When the transistor is OFF, the analysis of the output is simple: Iin = Iled, Pototal = Pled = Vled * Iin. Thus our measurement is exact in this case.

Let's turn to the ON state:

Note that Ie = Ibe + Ice, I1k = Ibe, Iin=Ibat=Iscr1=Ibe+Ice+Iled, and Vled = Vce.

As the current Ice is climbing up, so the coil connected to the collector maintains a voltage drop, we have Vin > Vce. On the other hand, the time interval for Ibe to rise to its working level is tiny, so most of the time,  Vbe+V1k = Vin + Vinduced (ignoring the resistance in the coil), where Vinduced is the induced voltage because the current in the other coil is increasing.

P1k + Pbe = I1k * V1k + Ibe * Vbe
                = I1k * (V1k + Vbe)
                > Ibe * Vin
                > Ibe * Vce.

From which we can proceed as follows:

Pototal = P1k + Pbe + Pce + Pled
           > Ibe*Vce + Ice * Vce + Iled * Vled
           = (Ibe + Ice + Iled) * Vce
           = Iin * Vce

Note that Iin*Vce is what we measured as  Pototal (to see this, Iin = Iscr1 = Ibat, Vce = Vled = V3), so it is indeed less than the actual Pototal.

On the other hand, the measured Pototal should be very close, as Ibe is relatively small to Ice on the average. The bigger the beta, the better the approximation. The gap can be roughly estimated by integrating Ibe * (Vin - Vce) during the ON state of the transistor (ignoring Vinduced), now (Vin - Vce) is the voltage drop over the coil connected to the collector, Ice * (Vin-Vce) is the power stored on that coil, which will be released through the LED later. However, Ice is increasing almost linearly from zero up to (beta * Ibe) [Ibe is relatively constant, so is Vin-Vce, during the ON state], therefore MEAN[beta * Ibe * (Vin - Vce)] during the ON state = 2 * MEAN[ Ice * (Vin-Vce) ] during the ON state. The stored energy MEAN[ Ice * (Vin-Vce) ] during the ON state is released later on the LED, which can be estimated by Pled * ( 1 - Vin/Vled) during the OFF state of transistor. From our previous tests, Pled ~ Pototal, therefore the gap is estimated to be 2 * Pototal * (1 - Vin/Vled) / beta, which is about 200*(1-Vin/Vled)/beta percent of the Pototal. If beta = 50, Vin = 1V, Vled=2V, the gap is then estimated to be 2%. Which is close to your 1.5%, and that 2% also included the 1k resistor. If assume Vinduced = Vin-Vce, as the coils have the same # of windings, the gap becomes 400*(1-Vin/Vled)/beta; in this case if beta=100, Vin=1, Vled=2, the gap should be 2%.

In conclusion: the simplified method of measurement gives a good underestimate of efficiency n.

@PhysicsProf:

It all Looks exciting -- look forward to your verified results.  And your encouraging words are appreciated. I will do my best to join you [might take some time, I need to get a scope and learn how to use it].

@feynman:

Thank you for your encouragement, and it is great that you could join the force here.

cheers, lanenal
« Last Edit: 2011-03-04, 06:20:34 by lanenal »
   
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One other potential problem in combining all the output powers, is we are less likely able to identify where or which device is causing our efficiency to be so high.

Hi .99: very good question you have raised out there -- at this moment I can't say much about how to identify which component is causing the high efficiency, but let's keep thinking about it. However, it could be the case that the high efficiency comes as the synergy of a few components. Another possibility is that some energy comes from the ether (or, if you don't accept ether, the magnetic-electric field) instigated by the make-and-break of the transistor and picked up by the coils. I don't know, guys, just my wild educated guess for you guys to think about.

Later on, we might want to do some fine tuning of it, varying the base resistor, the coils, the transistor beta (by using different transistors) , and measure the efficiency and see how it changes with those parameters.

If we just want to ascertain n > 1, which seems to be our near objective, then the simplified measurement is what I would prefer. To reduce the errors caused by the inaccuracy of scopes, it is good to follow this procedure:

1. measure V1, V2, V3 and calculate n1.

2. swap the probes for V1 and V3, and calculate n2.

3. calculate the final n = sqrt(n1*n2).

This way, relative measuring errors of the probes are canceled out, and the final n should be very accurate.  O0

cheers, lanenal
« Last Edit: 2011-03-04, 03:17:41 by lanenal »
   
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  Good comments, and good adventure.

So, I will attach a photo-composite below, showing the JT circuit and Pout and Pin (labeled on a white card) for this circuit, using my ATTEN 1062C.  
Conditions:  Jameco 1-1/8" yellow toroid which I wound bifilar, 13 windings, 24 uH in each winding.   Vbatt = 1.14 volts, actually from a power supply, which reads 58 mA current (input).  This is approximately the point at which the Green Power curves just touch the zero line -- higher voltage, and the curves move away from the zero line indicating a steady draw of current in addition the sawtooth).  Further, 1.14V is the Voltage for which I obtained the largest n with this particular toroid (according to my rough calculation).  You may observe in the photo that I am using a red LED for these tests.

Note, feynman, that the curves are considerably more interesting than what you found in Wikipedia.   Blue is the Voltage across CSR1, V2 in Lanenal's schematic.   Yellow waveform with Pout represents V3 (including the LED); yellow with Pin gives the V1 waveform.

I will leave it to you to examine the green curves for Pout and Pin -- using Lanenal's circuit (which i also depicted in the photo, because I printed it out this morning and used it).  Note that both Pin and Pout POWER curves come out Negative the way the circuit is hooked up per Lanenal's schematic.  

You can see from the curves that calculating the area under Pin is rather easy -- a triangular sawtooth.  Calculating the area under Pout is more challenging as it is an irregular spike -- and note that it reaches much larger peak power (and voltage) than the input.  I did measurements and calculations by hand on these waveforms to get n -- and found n to be somewhat larger than unity in this case (and a few others), but I'm awaiting runs with the Tektronix 3032 in order to get more reliable and definitive numbers.

Suggest you compare Pout and Pin green waveforms for yourself. 
   
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That's very interesting O0. I did a little marking and rough measuring, see attached. My estimation is that it is anywhere between 90% to 110%. Look forward to the numerical results.  
   
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