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Overunity SSG - 1.23 COP! (Corrected again)
GO DIRECTLY TO MY POST #15 FOR THE CORRECTED CALCULATIONS SHOWING 1.60 COP.
Hi everyone,
First of all, yes, I know the word "overunity" is an oxymoron - you can't have more than everything. But obviously this word has persisted for so long and it is known that it's intended meaning is for a device that is over 1.0 COP and that is why I used it.
This old dinosaur, my first ever SG from 12 years ago gives a 2.38 COP on the output battery and that doesn't even include mechanical work. That is just one recent test.
Circuit is MJl21194, both trigger and spike diodes are 1N4007 and base resistor is 60 ohms with a 1k 10 turn precision pot in series. Rotor is pink roller skate wheel from a $2 pair of roller skates from the good will with bearings in fair condition. I'm actually using neos - 3/8" thick double stacked neos...1 recessed into the wheel flush and the 2nd on top of that. Magnets are every 90 degrees and it is running in the enhanced mode described in Bedini SG - The Complete Beginner's Handbook. The power windings is 23 awg and trigger is 26 awg. The power winding is 4 ohms so that tells you how long it is. I built it originally with a MPS 8099 and followed the instructions in the original SG diagram posted on Keelynet WAY back.
For this particular test, I used different batteries than are shown in the pictures. In the pictures are 12v 7ah gel cells that were from an electric scooter. I used to charge those up with a bicycle wheel trifilar SG and used to drive it down to John Bedini's shop when I worked at a pulsed light healing device company down the street about 10 years ago or so. They're not in perfect shape but it is a miracle they're even half way good considering the agony and torment that I've put them through.
Anyway, for the COP test I did yesterday, I used 18v nicads from a Black & Decker Grasshog trimmer. They are rated at 1200 mah or 1.2 Ah.
Looks like this:
That one is actually a 2.0 Ah model, but the ones I have are 1.2 Ah that have been heavily used for the last 5 years. 90% of the time I charged it up, I used my 1AU Tesla Charger.
The input battery was fully charged up and so was the secondary battery. The secondary battery, I put a fixed C20 load (300 ohms) across the secondary to drain it overnight. I was going to stop it at 18.0 volts exactly but didn't catch it until it was at 17.41 volts.
I then disconnected it and hooked up the run battery to the SSG in the pics above and got it up to the fastest speed for the least draw. With a coil this small, you don't need the neon for protection and can run it without a secondary battery hooked up.
Anyway, after I had the base resistance where I liked it so it would be the fastest with the least draw and the lowest duty cycle, I hooked up the output battery.
I used a Fluke Scopemeter 123 for the test. It is 2 channels. I had a 0.25 ohm calibrated current sensing resistor on the ground line of the input battery and had both channels across that resistor.
Input battery went from 18.83 to 18.20 and I ran it with a battery on the back end for 32 minutes.
Before I give you the real numbers, I want to give you numbers that will handicap it to show the greatest draw - more than it actually drew so I have a bigger number to beat with the draw down test on the secondary battery.
I will use 18.83 volts (starting voltage and NOT average voltage) to calculate draw for entire running time. Voltage across the 0.25 ohm resistor was 0.0347 volts when the run started. So again, I'm using the HIGHEST numbers to show what it drew to be conservative. If I used lower numbers, it would be easier to beat so let's see what this shows us first.
0.0347 volts / 0.25 ohm resistor = 0.1388 amps of current. 0.1388 amps X 18.83 volts = 2.614 watt seconds per second. 2.614 watts X 25.3% (using the largest duty cycle towards the end, again to handicap the results to the max) = 0.6612418 joule seconds per second "burned" from the input X 60 seconds = 39.67 joule seconds per minute X 32 minutes of running time = 1269.58 joule seconds burned from the input.
The volt reading across the resistor was done using DC Mean instead of RMS since at these relatively low speeds it is accurate. If we're running in the mhz or something, then we'd definitely want to use RMS. The Frequency was about 300hz, which is 18000 cycles per minute divided by 4 magnets every 90 degrees = 4500 RPM at the start just to give you an idea of what the wheel is doing. Anyway, 300 cycles per second is very much in the slow range to use DC Mean on a scope to measure the voltage across the current sensing resistor.
At 32 minutes of run time, the output battery was disconnected and a C20 load was applied. 1.2 Ah C20 rate is a 60ma current draw. The battery voltage I used was 18.0 v / 0.06 amps = 300 ohm load. I used 3 X 100 ohm 10 watt power resistors with the 0.25 ohm current sensing resistor in series on the ground side of the string.
The starting voltage was 18.7 and it took 45 minutes to go down to 17.41 v where it was drained to before it was charged up.
AGAIN - to double handicap the numbers in favor of conservative numbers, I'm going to calculate the total draw using the voltage of 17.41 (when the battery was drained) so it will show that I drew the least amount from the output battery.
at 17.41 volts, the voltage across the resistor was 0.015 volts. 0.015 volts / 0.25 ohms = 0.06 amps. 0.06 amps X 17.41 volts = 1.0446 watt seconds per second and of course we leave it at that since the fixed resistive load is at a 100% duty cycle.
1.0446 watt seconds per second x 60 = 62.676 watt seconds per minute X 45 minutes until it hit the 17.41 volt goal = 2820.42 joule seconds burned from the output recovery battery, which was charged from the input.
2820.42 joules on the output battery / 1269.58 joules on the input battery = 2.22 COP and that does NOT include any mechanical work.
We used the highest possible numbers to show a large input and the lowest possible numbers on the recovery battery to show a small output - handicapping it in both directions for the benefit of the doubt.
Using the real averages, averaging the average of the different geometrical ramp downs on the voltage grahps, the average voltage was 18.515 with a voltage across the current sensing resistor of 0.0346 volts. 0.0346 / 0.25 ohms = 0.1384 amps X 18.515 = 2.562476 watts X 24.90 average % duty cycle = 0.638 watt seconds per second X 60 = 38.28 watt seconds per minute X 32 minutes = actual joules burned on input of 1225.07.
Using real averages for draw down test on output battery, considering actual averages of both geometrical ramp downs of the graph, 18.25v for 14 minutes at 0.0155 volts across resistor = 0.0155 / 0.25 = 0.062 amps X 18.25 v = 1.1315 watt seconds per second X 60 sec x 14 minutes = 950.46 joule seconds burned.
Then the second part of the graph average is 17.6 volts with 0.015 volts across 0.25 ohm resistor = current of 0.06 amps x 17.6 volts = 1.056 watt seconds per second x 60 seconds = 63.36 watt seconds per minute X 31 minutes at this average = 1964.16 joule seconds burned.
950.46 + 1964.16 joules burned on the output until battery got back down to 17.41 volts = 2914.62 actual joules burned on output battery.
2914.62 divided by 1225.07 = 2.38 COP and that still doesn't include any mechanical work added to that. With mechanical work, will be about 2.8.
Even with handicapping the input and output for the worst case scenario, the COP is still 2.22, but using the real averages, it is 2.38 COP and that is without any mechanical work added to the equation.
The output battery obviously will recharge itself a bit and some skeptics will grip about C20 being too low of a discharge. Obvoiusly if we use a C50 rate, we could probably wind up with a COP of 5+, but C20 IS realistic. And with these numbers, I could do a C10 rate and would probably still beat 1.0 COP easily.
Is my little SSG "overunity"?
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