[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Sold state IGBT disruptive coil spark gap idea

Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>

Hi DC,

I've run computer simulations and it seems that these high BPS's are very necessay when configured STR just to control the voltage rise. Even 240 BPS sync wont control the rise if STR. Have you tried a LTR PIG design and looked for optimum BPS?? either sinc or async???

Gerry R.

Original poster: "D.C. Cox" <resonance@xxxxxxxxxx>

Pole pig powered coils seem to really "blaze" around 450-550 bks/sec. We usually run an 18 inch dia G-10 rotor with 17 inch dia. electrode spacing, 10 electrodes per rotor, and run at 3450 rpm for a really hot output with most of our pole pig designs. The sparks grow amazingly fast and are really hot when running 30-70 amps on our designs using .06 to 0.1 uF of capacitance. The large rotor insures fast quenching and seems to work much better than slower 1725 rpm designs. If anyone contemplates running at this speed --- always use a competent machine shop to do your rotor work. Flying nuts & bolts and broken tungsten shards at 3450 rpm speeds with this large of dia. rotor are killers!!

Dr. Resonance

Original poster: FutureT@xxxxxxx
In a message dated 4/30/06 6:36:14 PM Eastern Daylight Time, tesla@xxxxxxxxxx writes:

From what the good Dr. has mentioned, he's building loosly coupled
coils, but they are also running closer to Cres by about 18% than the
standard 1.6 x Cres, so his cap voltage is getting to potential
sooner and bps is a little higher.


In that case then other folks who run at higher bps using pigs
or PT's, or NST systems with close-set gaps, should see this
same effect of being able to lower their secondary until the
streamers get shorter without getting racing sparks
(at least up to some power throughput level).  Has anyone
else noticed this?

I agree that coils which use a smaller bang size with higher
bps should be less likely to form racing sparks for a given
streamer length.  Also tighter coupling should be safely
achievable.  It should be possible to get longer sparks
from a given secondary coil and a given toroid size using
small bang/higher bps also.  This is because smaller
bang/higher bps systems develop spark length more via streamer
"growth due to fast repetition", than via bang size.  However
the spark length for a given input power tends to drop as the
bps rises past some rate.

Perhaps you could add a feature to your excellent JavaTC
program which would predict the k point where racing sparks
would occur for a given coil, power level, bang size, bps,
toroid size, etc.  It could get tricky, especially since racing
spark causes may not yet be fully understood.  Still some
empirical info might be able to be utilized with multi-dependent
factors, etc.  The study of such things might lead to new
insights or discoveries in that area.