RE: Sold state IGBT disruptive coil spark gap idea

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Vardan <vardan01@xxxxxxxxxxxxxxxxxxxxxxx>

Hi,

Late report...

It was trivial to add the diode tonight so I did...

It fixed everything!!!!! :-))))))))))))))))))

The gate drive voltage now locks right in at about 27V just like it 
is supposed too (these are all like 25kB "little" files now ;-)):

http://hot-streamer.com/temp/SIDAC-IGBT-GAP-001.gif

After the first peak, the IGBT is locked in good and hard ;-))

It "stays" on just like it is suppose to too :-))  That timing is 
trivial to change...

http://hot-streamer.com/temp/SIDAC-IGBT-GAP-002.gif

I pulled out the jumper so the module is running at the full 900V here:

http://hot-streamer.com/temp/SIDAC-IGBT-GAP-003.gif

No problem at all running 150 amps :-)))

This is the current through and voltage across the gap:

http://hot-streamer.com/temp/SIDAC-IGBT-GAP-004.gif

Power dissipation is high:

http://hot-streamer.com/temp/SIDAC-IGBT-GAP-005.gif

"But" there is "no where else" for the power to go except the gap in 
this case.  The ringdown seem equal to a direct wire short.  It 
"needs" a secondary ;-))) :

http://hot-streamer.com/temp/SIDAC-IGBT-GAP-006.jpg

Efficiency seems to be roughly 60% so the rest of the power is in the 
coil, cap, and wiring...

Here is the board front:

http://hot-streamer.com/temp/SIDAC-IGBT-GAP-007.jpg

And back:

http://hot-streamer.com/temp/SIDAC-IGBT-GAP-008.jpg

I suspect is should be a perfectly stackable 900V 500A module.  Might 
need resistors still across the SIDACs for stability but that is a 
tiny thing (I think Peter mentioned this)....  It should not be "blow 
up able", but NO direct streamer hits (maybe the gate circuit could 
"take it" though...) ;-))  Looks like around $12/900V of 
gap...  Might be real good for lower voltage MOT coils ;-))  Almost 
"any" IGBT with diode could be used.

Sync gaps are a little problem, but the string could be fired "early" 
by shorting a small portion of the gap with conventional 
electronics.  A say 2000V section could be "triggered" and the other 
modules would follow...  Perhaps the gate drive voltage circuit could 
run timers or even PICs...  This is all "public domain" so I add 
those comments just the "break the patents" ;-))

The days of conventional coil "spark gaps" making "bright light" and 
"load noise" are now probably numbered :-)))

Party hardy!!!!!!!!!!

Cheers,

	Terry