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Author Topic: Reliable Measurements and Simulations: Power In and Out and Efficiency n  (Read 51372 times)
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@99

With reference to the last sim you posted:

Reply:#72  prof_gl_scope06.png
http://www.overunityresearch.com/index.php?action=dlattach;topic=773.0;attach=4526

Did you really use 8H for L1 & L2 in that sim???
   

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It's not as complicated as it may seem...
@99

With reference to the last sim you posted:

Reply:#72  prof_gl_scope06.png
http://www.overunityresearch.com/index.php?action=dlattach;topic=773.0;attach=4526

Did you really use 8H for L1 & L2 in that sim???

No, it was not 8H.

The cool thing about SPICE when you begin to use non-linear cores as the coupling media, is that the component values change from inductance to the number of turns. So in fact the "8" shown means "8 turns". The core material and core size/area is known, so all that is needed is the number of turns of wire on that core.

 8)
.99


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"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
   

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

I think you are mistaking the data taken with the bad probe connection with the data acquired later (4 attachments shown above), which have outputs typically in the tens of mW range; although for the 1 LED case, Pout was only about 1.1 mW.  Note the summary I provided (output power in bold here):

So, three voltages and the calculated n values (all data are attached below, starting with the 1.46 V = battery voltage run)
Vin   Pin(mW)   Pout (mW)      n
1.0   3.2          1.7             53%
1.46 32.9        19.7            60%  <--  repeated for numerous cycles, same n found
1.46   30           21             70%  <--  .99's SIM for comparison with above... appears fairly consistent to me
2.0   105.2      86.9             83%

1.46  10.5       1.1          10.5%

I'll comment on the waveforms later; gotta run to a community meeting this pm.


OK professor, that is what I meant by "if this was not a error". Thanks.

Still, the 1.1mW is quite low compared to 20mW, and esp. if the difference in apparent lumens is minimal. It would be interesting to focus on this one LED for some time, to determine if it really is using only 1.1mW of power. Perhaps there is a new ultra-low power mode of LED drive yet to be discovered here?

Cheers,
.99


---------------------------
"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
   
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@99

With reference to the last sim you posted:

Reply:#72  prof_gl_scope06.png
http://www.overunityresearch.com/index.php?action=dlattach;topic=773.0;attach=4526

Did you really use 8H for L1 & L2 in that sim???

Good call duff.  This reminds me of something.
ION,

Here are the results of the tests with a core-type unit (3C90 material). I ran 3 tests; 1LED, 2LEDs, 3LEDs in series. Efficiencies computed in each case with LED(s) terminated at GND and at Vbat. All LED powers added together in cases where there is more than one.


1xLED

GND Connection:

Pbat: 61.3, Pled: 25, n=40.8%

Vbat Connection:

Pbat: 63.7, Pled: 18.08, n=23.38%


2xLED

GND Connection:

Pbat: 75, Pled: 12.5+12.5 n=33%

Vbat Connection:

Pbat: 74, Pled: 10+10, n=27%


3xLED

GND Connection:

Pbat: 79.8, Pled: 8.16+8.16+8.16, n=30.6%

Vbat Connection:

Pbat: 78.1, Pled: 7.07+7.07+7.07, n=27.2%


I suspect this trend will continue while adding LEDs in series, until finally, the two efficiencies will equal out at 0%.

In all the cases above, a GND connection shows a better efficiency. Unless this simulation is not telling the truth, I'd be inclined to always connect my LEDs to GND, if I was indeed a Joule Thief enthusiast that is.  ;)

.99

Professor, can you increase the number of LEDs in series and check for efficiency next time?  I suppose if we can transfer as much as energy in voltage instead of current.
   
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OK professor, that is what I meant by "if this was not a error". Thanks.

Still, the 1.1mW is quite low compared to 20mW, and esp. if the difference in apparent lumens is minimal. It would be interesting to focus on this one LED for some time, to determine if it really is using only 1.1mW of power. Perhaps there is a new ultra-low power mode of LED drive yet to be discovered here?

Cheers,
.99

Right -- and I like Gibbs' suggestion also:
Quote
Professor, can you increase the number of LEDs in series and check for efficiency next time?  I suppose if we can transfer as much as energy in voltage instead of current
.

Sure, this will be interesting... I'll start a list of things to check empirically with the Tek 3032...  I learn a lot each session.
I'm just about ready to agree with Feynman, however -- that the JT-type circuits are not likely to be much overunity...   In any case, I love to learn.

   
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I don't think it's OU either, but IMO, it's going to be an epic battle between sim and scope.  ;)
   
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...
I should also note that using the 1X probe causes a change in brightness of the LED...  I believe this may be due to the capacitance of the probe itself.
...

I confirm this fact, even in 10x mode which is the usual position of my probes when signals are strong enough.
I'm still playing with high Q and Stiffler like circuits, whose capacity is around 1 or 2pF and  frequencies between 2 and 30 Mhz.
A probe changes noticeably the resonant frequency, even if it is quartz crystal controlled. When connected to the hot point, it becomes the dominant capacity. I have to disconnect the probe and to put it next to the hot point of the resonant circuit, i.e. to reduce this parasitic capacity down to 0.1pF or less, in oder to check the real natural resonant frequency of my circuit.

   

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Quote from: poynt99
Itsu,

The voltage probes are not on any particular "setting" actually. The RMS voltages that you see the scope displaying, are there for "interest" sake only. The MATH multiplication is always performed using the raw data samples within the scope. With this now acquired p(t) wave form trace, we use the scope "measurement" functions to perform a MEAN computation on this red MATH trace, and it displays that for us as well. This is the one we are interested in.

Hope that clears things up for you Itsu.


It does Poynt99,  thanks again.

As my channels can only be set at Cyc RMS, Mean or P2P, and none of those show any creditable values when measuring Pout using the csr2 resistor (using the multiple DDM/RC method for Pin), i can not make any usefull power calculations, so i will refrain from posting any.

I can confirm same behaviour when using the probes in the 1x position that the normal polarity (dim) led goes out when attaching.

Regards Itsu
   
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Thanks, Itsu -- and EMDevices! I had a bit of a sleepless night as I realized that with your circuit (attached again), there could be quite a bit of current flowing through CSR2, ie through the LED, without this being detected in CSR1 which measures the NET flow.  That is, the effectively-recycling current through L1 and the LED could be quite high relative to the current flowing through CSR1.   This would also explain/allow for the brightness of the LED as we have been puzzling about (see above discussion).

Further, I will add a CSR3 (1 ohm) south of L1 in order to compare the currents flowing through L1 and the LED -- and I want to look at the phase relationships also.  Whew!  This could get interesting again as Gibbs noted.  (Good point, Gibbs)  Thanks again EMD, and my apologies for being so dense on this issue in the past.  

Also, I think the SIM with CSR2 and CSR3 would be interesting to see...  not sure the sim and the empirical circuit are yet in agreement since the SIM has the power in one of the  LED's (in the two LED circuit) at zero when it is actually lit....  
   

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

I can confirm same behaviour when using the probes in the 1x position that the normal polarity (dim) led goes out when attaching.
Regards Itsu

That is quite interesting Itsu, thanks.

As I mentioned before, I think it might be possible to develop a new low-power mode of LED drive, if we can perform a few more controlled tests of the hypothesis, that being the LED can be illuminated almost to full brightness with extremely short pulses, or perhaps with a pulsed electric field which is below the forward turn-on threshold of the LED.

.99


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"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
   
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Further, I will add a CSR3 (1 ohm) south of L1 in order to compare the currents flowing through L1 and the LED -- and I want to look at the phase relationships also.  Whew!  This could get interesting again as Gibbs noted.  (Good point, Gibbs)  Thanks again EMD, and my apologies for being so dense on this issue in the past.  


Alright, I have added 1 ohm resistors as advertised, CSR2 (voltage drop V4) south of the LED oriented as EMD recommended, and another (CSR3) south of L1 (voltage drop I'll call V5).
To measure power across the LED, I have the ATTEN provide the waveform for V3*V4, then I take the integrated area for one cycle (by hand).
Similarly,
To measure power across L1, I have the ATTEN provide the waveform for V3*V5, then I take the integrated area for one cycle (by hand).

To measure power INPUT, I have the ATTEN provide the waveform for V1*V2, then I take the integrated area for one cycle (by hand).

Of course, with the Tek 3032, it will calculate MEAN Power in each case, saving me a lot of trouble.

I find the relative power varies with applied voltage Vin, with more power going to the LED with increasing Vin, that is, P-LED/P-L1 increases.
Using x10 probes and at 1.83 volts on my system described in earlier posts, I find that PL1 is approximately 40% of the power dissipated in the LED leg.  This is not negligible...
but I'm unsure just how to incorporate P-L1 into a calculation of n, because the inductor L1 is not a simple resistive load...

Do I simply take n = (P-LED +P-L1)/ Pin  ? 

We're to the point where the pieces are measured separately and can now be put together... in principle.  If the above is not the equation for n, what is?
   

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It's not as complicated as it may seem...
Just a friendly reminder, that before the single-CSR method was proposed, on Feb 27 I had proposed (and it was agreed upon later I thought) that the correct method for determining the power in each separate component involves it's own CSR. See the schematic below, and note that I made mention in note 5) that a CSR for the transistor could also be added, i.e. CSR3.

It seems we've gone full circle, and as a reminder to mitigate errors, we need to ask ourselves "what is the VOLTAGE ACROSS and CURRENT THROUGH the component I am interested in?"

.99


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"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
   
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   Gibbs quotes .99:

Quote
Here are the results of the tests with a core-type unit (3C90 material). I ran 3 tests; 1LED, 2LEDs, 3LEDs in series. Efficiencies computed in each case with LED(s) terminated at GND and at Vbat. All LED powers added together in cases where there is more than one.

1xLED

GND Connection:

Pbat: 61.3, Pled: 25, n=40.8%

Vbat Connection:

Pbat: 63.7, Pled: 18.08, n=23.38%

Just what does this mean, GND connection, as opposed to Vbat connection?  Don't think I understand fully.  Somehow, there needs to be a completion of the circuit back to the battery (-), right?   Thanks.
   
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There is an outstanding question for .99 in my previous post, above, which I hope you'll address, .99 (regarding GND connection).
  
In the last few days, I have been running the Joule Booster JB (or "reverse JT") circuit attached, with LED direction as urged by EMDevices. (thanks!)
There are a few changes from that diagram,
1.  Add a variable resistor between the LED and point P21T ("V3" point) -- I decided to try dumping power here, and adjusted the R till it suited me (looking at Pin on the oscilloscope).
Later measured this Rvar = 1061 ohms.

2.  Added a cap of 151 pF between the same point P21T and P22T
My goal was to minimize Pin while maximizing Pout, looking at the power waveforms on my ATTEN, and those mods were what I came up with empirically.

Here are the other parameters of the JB set-up:
Vbatt = 1.3 V (older AA battery)
1888 ohms (including a second variable resistor) instead of the 1K ohm R shown in the attached schematic
MPS2222A transistor
151 pF cap along with L2 = 80 uH
L1 = 67 uH

Now, attached is a photo of the JB running and the red LED lit quite brightly.  What surprises me is that the LED is lit up when there is a 1061 ohm resistance (1.06Kohms) in SERIES with the LED!


I have some results showing Pin and Pout for this circuit, but first I would like to ask .99 (or anyone!) to do the SIMULATION for this circuit, including the 1.06Kohm R in series with the LED, to see what power is going through the LED-output-leg of the circuit.  Is the LED lit up -- in the sim?


I think there may be something unusual here, based on this result and Power measurements with this circuit, but before going on would like to see what the SIM result is...

PS -- this is NOT an April Fool's joke!
   

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It's not as complicated as it may seem...
  Gibbs quotes .99:

Just what does this mean, GND connection, as opposed to Vbat connection?  Don't think I understand fully.  Somehow, there needs to be a completion of the circuit back to the battery (-), right?   Thanks.

Sorry Professor, I did not see this post/question.

This is referring to where the LED is terminated. It either goes from the transistor collector to ground (as per how we normally see it in our JT circuits), or the LED goes up to the battery rail (as a flyback diode would be situated as shown for eg.).



Hope that makes sense now.

.99


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"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
   

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

It does not surprise me that the LED still works even with a 1k or 2k resistor in series.

What is the voltage on the collector?

Also note that in a previous test, you had very little power in the one LED, and it was still illuminating. There may be something at play here, as I have already mentioned a couple of times.

No need to do the Sim, I know what it will show, almost no power to the LED.

.99


---------------------------
"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
   
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.99: 
Quote
It either goes from the transistor collector to ground (as per how we normally see it in our JT circuits), or the LED goes up to the battery rail (as a flyback diode would be situated as shown for eg.).
Alright-- thanks for the response.

Professor,

It does not surprise me that the LED still works even with a 1k or 2k resistor in series.

What is the voltage on the collector?

Also note that in a previous test, you had very little power in the one LED, and it was still illuminating. There may be something at play here, as I have already mentioned a couple of times.

No need to do the Sim, I know what it will show, almost no power to the LED.

.99


Positive from the battery connects direct to the collector, so it is at the battery voltage.
No Sim:  OK, it seems that we need real measurements/ observations at this point.
   

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It's not as complicated as it may seem...
Positive from the battery connects direct to the collector, so it is at the battery voltage.
No Sim:  OK, it seems that we need real measurements/ observations at this point.

Indeed, that post of mine was in reference to the standard JT circuit.

Right, forgot. Let me re-phrase the question; what is the voltage on the emitter? ;)

I suspect it is showing a high negative swing?

.99


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"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
   
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Indeed the emitter voltage has a high negative swing.  

Corrected:  Vrms for Vemitter is 1.8 volts...  not surprising.


Conditions are as given a few posts earlier, except the refreshed battery has Vin = 1.46 volts now.

PS -- wife and I will be traveling, limited computer contact for about twelve days ...
« Last Edit: 2011-04-04, 18:02:18 by PhysicsProf »
   
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 Taking a probe across the LED, I find the voltage to swing from +1.4V to -!.4 volts.
 Taking a probe across the 1.06Kohm resistor in series with the LED, I find the voltage to swing from +1.0V to -!.0 volts.

I don't see how the red LED can light up under these conditions, but it is lit nevertheless.
   
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In the last few days, I have been running the Joule Booster JB (or "reverse JT") circuit attached, with LED direction as urged by EMDevices. (thanks!)
There are a few changes from that diagram,
1.  Add a variable resistor between the LED and point P21T ("V3" point) -- I decided to try dumping power here, and adjusted the R till it suited me (looking at Pin on the oscilloscope).
Later measured this Rvar = 1061 ohms.


Correction:  Rvar = 2.44 Kohms  (re-measured, completely isolated from other circuit elements)

And replaced the red LED with yellow LED and also green LED --  yellow or green also lit up dimly using a single AA battery for input voltage of about 1.45 V.
Travel begins in earnest today -- wishing you all well as my computer contact will be limited for a couple of weeks now.
   

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

Enjoy your trip.

.99


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"Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa
   
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  Suppose my questions are

1/ How much energy required to charge an inductor to 1/2Li^2.
2/ How much energy can be gain from 1/2Li^2.

Or let me rephrase it in Newtonian equilvalent

1/ How much energy does it takes to cause a mass M to velocity V from relative rest position.
2/ How much energy can we gain from stopping mass M with velocity V to its relative rest.



I'm not surprise if n approaches 2 in this setup.
   
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  I'm back from the trip...  a long one!

  Yesterday, I tried to record ENERGY-IN and ENERGY-OUT from a JT-analog circuit, by using CAPACITORS to provide the input energy, and to collect the output energy.  It worked, sort of.
But the efficiency numbers came in around 70%, which was lower than what I had obtained using the MEAN Power calculations, using a Tektronix 3032.  I would like to understand this result.

  So, I recalled something about apparent non-conservation of energy when stored energy in one cap flows to another cap -- with energy loss being evident.  I tried this experiment using two identical 10,000 uF caps.  The first was charged to 2.66 volts.  Stored energy is 1/2 CV**2.  

Then I simply connected this cap to its twin.  Then the voltage on each one was the same, 1.33 volts -- of course, by charge conservation:

V = Q/C   so by doubling C, the voltage is halved.

BUT -- consider whether ENERGY was conserved:

E = 1/2 CV**2    -- so HALF of the initial energy was lost in the process of simply connecting the charged cap to a twin uncharged-cap!  Work it out -- we have two caps in the end, but the voltage was down by 1/2, square that -- energy in each is 1/4 of the initial energy.  Two of them, so 2 * 1/4 (Einitial) = 1/2 (Einitial) in the final situation.

What happened to the "missing" energy, or did I do something wrong?  (HINT -- if you think I did something wrong, remember I conserved charge but not energy...  it appears in this simple experiment, you can't have it both ways.)

OK -- prove the professor of physics wrong...  OR if you agree with me that energy was lost, then tell me

HOW do we determine n (in a JT-analog circuit, say) using CAPS to provide the input energy, and to store output energy?  That is, do we consider that energy will be LOST necessarily -- as is the case when we directly connect CAPS as in my test above.?  (That is, is the n = 1/2 in this case due to the circuit "inefficiency", or simply due to the requirement of charge conservation coupled with the nature of capacitors?  are direct-connecting wires really just 50% efficient?  I don't think so...)

   
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  PS -- the above questions are serious, not some sort of game.  Although I did enjoy posing such questions to students in my classes, I will certainly admit.

 I would like to know how to determine efficiency n of circuits by various methods -- in this case, how to ACCURATELY use capacitors to provide input energy and to store the output energy.
   
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