Eldarion and Bruce's build of Bob's Energy Converter

[MeggerMan]

Hi Mark,
To get a single pulse to fit into a cable means that you need so have a pulse shorter than the VoP (velocity of propogation) of the coil.
According to Wikipedia: http://en.wikipedia.org/wiki/Velocity_of_propagation
For example a cable that has a VoP of 70% of speed of light means that the signal will travel 1 meter in 4.7ns
The only thing is does coiling up the cable change the VoP of the wire dramatically?
Certainly a wire of about 3-4 meters long should be enough to allow a pulse of about 10ns to fit inside the coil.
As you know IXYS have a range of mosfets and drivers that can handle these narrow pulse widths:
http://www.ixysrf.com/app/high_voltage.html but at a price though.
Could get expensive if things go bang during testing.
In my short experience I think the mosfets are OK to overload with current, its just the drivers that you have to be careful with. I suppose you could use some very low value resistors to limit current. Perhaps a carbon brush could be used.

With the idea of allowing the pulse to travel around the coil continuously you could use a schottky diode in series with the start and end of the coil wires. Can a schottky diode handle the switching speeds though?

Regards
Rob

[MarkSnoswell]

@Meger Man
I dont wan to divert the thread here so just a quick note. Yes -- a coil as a tranmission line can have dramatically lower transmission speeds. If we have interactin with a coer -- aluminum even then the transmission velocity caould be dramatically lower. This is expecially releveant if there is sone phonon-electron spin interaction in the core that is retarding the wave.

[Bob Boyce]

All,

Just to let you know, I have found yet another large instability in my pulse generator, so the above null results are probably incorrect.  The instability is quite the difficult bug to smash!

Eldarion

What sort of instability are you seeing eldarion?

Hey, I just won high bid on a pair of Tektronix 2445A scopes on ebay for cheap

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=230185659755
and
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=230185659791

I figure if it comes down to it, it's better to fry a cheap scope than the one I paid a lot for new. Besides, can't hurt to have spares that are the same as my main scope ;-)

Bob

[eldarion]

Hi Bob,

I was seeing an odd, repetitive pulse ordering error, whereby the correct pulse sequence would be generated for a little while (maybe a few milliseconds) and then the position of the F1 pulse would shift to a completely wrong location in the waveform.  I had not noticed it until recently because I had never expanded the timebase of the scope beyond a couple of cycles!

I have since completely rewritten the pulse generation core from scratch, and that bug seems to be gone.    The new core checks out reliably over quite a number of cycles (20+), and the frequency jitter I was also seeing before is now completely gone!

Ahh, the joys of digital logic design.

Eldarion

EDIT: Here is a scope shot of the MOSFET driver outputs with the new core.  Notice the lack of jitter!
http://www.falconir.com/pics/mosfet_driver_chip_outputs_fixed.jpg

[Bob Boyce]

Hi Bob,

I was seeing an odd, repetitive pulse ordering error, whereby the correct pulse sequence would be generated for a little while (maybe a few milliseconds) and then the position of the F1 pulse would shift to a completely wrong location in the waveform.  I had not noticed it until recently because I had never expanded the timebase of the scope beyond a couple of cycles!

I have since completely rewritten the pulse generation core from scratch, and that bug seems to be gone.    The new core checks out reliably over quite a number of cycles (20+), and the frequency jitter I was also seeing before is now completely gone!

Ahh, the joys of digital logic design.

Eldarion

EDIT: Here is a scope shot of the MOSFET driver outputs with the new core.  Notice the lack of jitter!
http://www.falconir.com/pics/mosfet_driver_chip_outputs_fixed.jpg

Eldarion, that pulse pattern does look to be right, if the channel orders are correct that is. Hard to tell without channel references ;-)

Now when you go to test, please try to keep in mind the directions of energy flows, both within, and through the circuits. Remember the two drawings that showed the windings? Where in the first one, the capacitor shorts out a very large portion of the captured LEM energy to ground, while the second one does not lose as much. Keep in mind the reference points and potential differences.

http://www.overunity.com/index.php?action=dlattach;topic=2865.0;attach=11978;image
http://www.overunity.com/index.php?action=dlattach;topic=2865.0;attach=11980;image

Rich in FL has also had success with another load configuration, where the secondary is referenced to HV on one side and the bulb load is directly across the secondary with the DC blocking cap in series with the bulb. He said it takes a wider pulse width to get things going, but if you increase the primary pulse voltages, you can reduce pulse width. It is with this configuration that he was lighting, and recently burned out, a 75 watt 120 volt bulb, and the bulb continued to arc internally. Remember, he can only run in pulsed mode, as he has no controller capable of phased rotational drive.

Bob