Quantum Energy Generator (QEG) Open Sourced (by HopeGirl)

[TinselKoala]

I think you might have errorred here in your calc of Vars.  It's a vector triangle so: sqrt(618*618 - 451*451) =  423 var.
Your pf of 0.73 is a cos(theta) of almost 45 degrees.

Yep. If you go up aways you'll see that the scope is reporting a phase angle of 42 degrees.

[isim]

@Farmland
"And the resistor is a wire one."
Do you mean made of a wound  wire or not?
All CSR must be without inductance!
@+

[TinselKoala]

The ones I'm using are the Ohmite non-inductive Ayrton-Perry wirewound, they are supposed to be less than 1 nH each according to the spec sheet. They were generously donated to the lab for the LMM project. They are about 80 cents US apiece from DigiKey.

[Farmhand]

I think you might have errorred here in your calc of Vars.  It's a vector triangle so: sqrt(618*618 - 451*451) =  423 var.
Your pf of 0.73 is a cos(theta) of almost 45 degrees.

Yes of course you're right, I got confused. And if I use the current value of 0.58 amps from the calculation I get ie. 340 x 0.58 = 197
then 197 x 0.73 = 144, so that is 144 VAR ? Sounds better. pweww.ee with 6.3 Watts input. = 22 to 1.

The resistor is a 5 Watt power resistor 0.1 Ohms.

Tinsel that sounds about right except the frequency might be a tad lower and the capacitance more. I'll need to get more accurate measurements of inductance ect. thanks for the links.

..

P.S. What about the the CSR from a killo watt meter.

..

[TinselKoala]

I found the "second edition" of the Measurement Report from the FTW people.
https://hopegirl2012.files.wordpress.com/2014/05/morocco-qeg-june-2014-test-and-measurement-report-v2-011.pdf

Below I show the Figure 14 scopeshot. This is an actual output scopeshot, showing the secondary voltage and current while driving a full load of light bulbs. Just above this shot is a photo of their input wattmeter showing 607.4 W input to the motor drive.

Let's analyze this shot and the numbers that appear above it.
First we note, as usual, that the channels are AC-coupled. Fail, but ignore that for the moment. Next we note that the attenuations appear to be set to 1x, not to  match the probes of 1000 x (voltage) and 10x (the current transformer). Another fail but not serious as long as we know the probe factors.

OK, so the screen shows a distorted kind-of-sine wave, and the zero-crossings are coincident, or near enough, so we can say that the phase angle is zero, as expected for the resistive light bulb load. And the frequency checks out as about 145 Hz (not 400!).

Now the numbers: the scope says 1.59 V p-p and 88.8 mV p-p. Applying the probe adjustments and type conversion we then have indicated 1590 V p-p and 0.89 A p-p. Right so far? And in agreement with the text.

What are the rms values associated with those peak-to-peak values, assuming sine waves? 1590 V p-p = 562 V rms. But the text has 405 V rms. 
0.89 A p-p = 0.315 A rms. But the text has 0.23 A rms.  
Then they go on to calculate "peak" and "rms" POWER, giving those values as 1415 W p-p and 93 V rms (sic) as these values. WHAAT

The AVERAGE POWER of a zero-phase shifted sinusoidal current and voltage measurement is equal to Vrms x I rms. This represents the real power that is dissipated in a resistive load.  In this case, again fudging and using the sine wave calculation on the distorted waveforms, 562 x 0.315 = 177 Watts average power. "RMS Power" is meaningless in this context and shows that whoever wrote the report doesn't really understand what he or she is writing about.

This results in an efficiency of 177/607 = 0.29 or 29 percent.  But unlike in the disconnected, large VARs measurements that come after, they do not go to the step of computing efficiency for this _actual output_ measurement in the report.

Please check my work.  Can anyone explain to me the discrepancies in the calculated numbers?

http://www.referencedesigner.com/rfcal/vrms-to-vpeak-conversion.php