Bifilar pancake coil overunity experiment

[itsu]

I measure the bifilar coil used to have 2.7nF capacity, meaning a reactance of about 40 Ohm at 1.44Mhz.
So i guess that almost all (100%) input is going to be transferred to the load resistors so a COP=1 looks
fine with me.

Itsu

[ayeaye]

So 2.9 times measurement error, that's unimaginable. My result also went closer to COP 1, though always remained slightly higher than 1, but i think it's highly possible that when making it a bit more precise, it goes below 1, so it's not a significant result, a possible measurement error was finally higher than the possible overunity. But i used Hitachi analog oscilloscope and only started to develop my method of digitizing trace data using Inkscape. But they used top notch digital Tektronix, with all the capabilities.

[F6FLT]

Imagine an input power of 1mW that supplies a perfect LC circuit with a very high Q factor so that 2MW of reactive power is reached and stored in the system.
Suppose this system generates a useful power of 3mW, do you think you can easily measure a COP of 3?
When large powers are associated with small ones, measurement errors on small ones are not only imaginable but common.

[partzman]

Itsu,

I have several comments regarding your TK replication.  First, the phase angle is quite low which would mean the Q of your coil is low and/or you might carefully check the dot polarity of your coil connections.

Second, let's look again at your measurements and calculation.  You measure Vin = 1.9v crms, Iin = 47ma crms, Vout = 969mv crms, and the input phase angle as -61.85 degrees.  Therefore the Pin is 1.9*47e-3*cos(-61.85) = 42.13mw and Pout is .969^2/21 = 44.71mw for a COP = 44.71/42.13 = 1.061. 

Since these voltage and current measurements were taken on a cycle basis, I would be somewhat confident in the result.

However, the Math channel calculation may possibly be inaccurate depending on whether it was measured between the cursors or full screen.  You might want to check what cursor setting you had during these measurements.

Regards,
Pm

[itsu]

Hi Partzman,

thanks for the comments.

I hooked up the bifilar coil the same way TK did in his video and double checked the dot polarity of my bifilar pancake coil
to be the same as presented in the diagram which it does.

Thanks for the exact calculations of the data, indeed the COP comes out to be 1.061 and i did saw that, but consider
it to be in the margin of measurement errors.

The Math calculations where done using the full record (gating off) which i think is the most accurate.


When changing the dot polarity on one coil (input), things change of course and brings it somewhat more into the values
TK had, like 87° phase difference and similar voltage and current readings, however, the output drops dramatically
so the COP is 0.03 or so.

See screenshots below and calculations, so i think the first setup used was the proper one.


Scope Math (red) calulates the input to be 5.4mW
Manual calculation for input shows Vrms x Irms    x Cos (phi)    = P ave
                                                1.923x 0.05658 x Cos (-87.27) = 5.18mW   (similar as scope instantaneous calc's)

Pout = U²/R
        = 0.05833²/21
        = 0.16mW  =  160uW

So my setup and calculations then comes to a COP=0.03  or so



Regards Itsu