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Re: OLTC maggy - Modeling and "kickback"



Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>

What an odd thing to ponder...

"So we can't win!!  Since the voltage and current will always be 180 
degrees out of phase, we either have to loose energy due to "left over" 
primary cap voltage or left over inductor current."

Since spark gaps always* quench at a zero current crossing, the left over 
voltage probably gets burned up in the gap "flame".  Just 
waisted...  Probably a fairly big contributor to spark gap losses.  Thus 
comes into play those "sweet spots" of years gone by.  Those special cases 
where the losses, component values, coupling... all come into play to leave 
zero energy in the primary circuit just at the instant of the first notch 
quench....

Normal coils have far too many goofy things going on to really care.  But 
the precise OLTCs show this problem very well.

I think changing the coupling slightly would really help this.  Not sure if 
it would really help, but...  I guess I have the model working, so I'll 
search around...   Couldn't find one...  But second notch quenching at say 
73.8uS leaves far less energy in the system.  But the losses may make 
second notch quenching worse.

http://hot-streamer-dot-com/temp/OLTCsc30.gif

But the models seem to think it will give better performance:

http://hot-streamer-dot-com/temp/OLTCsc31.gif

Have to actually try that one...

If Steve tries the 'Maggy OLTC", Antonio's sweet spots may be really 
important.  Since the OLTC tends to have pretty low losses, it may follow 
the "ideal" cases well.

http://www.coe.ufrj.br/~acmq/tesla/magnifier.html

http://www.coe.ufrj.br/~acmq/tesla/tefp.html


Cheers,

	Terry

*DC Cox's high-speed super-multigap can actually break at full primary current!