Re: Auto Quenching - OOPs!! forget that one ;-)

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Bert Hickman by way of Terry Fritz <twftesla-at-qwest-dot-net>" <bert.hickman-at-aquila-dot-net>

Terry,

Now THAT looks better... :^) Couldn't understand how Auto-Quenching
worked assuming reasonable losses... thanks for the clarification!

-- Bert --
-- 
Bert Hickman
Stoneridge Engineering
"Electromagically" Shrunken Coins!
http://www.teslamania-dot-com

Tesla list wrote:
> 
> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>
> 
> Hi All,
> 
> Disregard yesterday's post and my ideas about "auto quenching".  As it
> turns out, the effect does not exist.  It was just a computer modeling
> error on my part.  The way I had it set up allowed the firing voltage to
> vary as I changed the coupling.  As I worked with my coil last night it
> seemed that something was really wrong with the idea.  I churned through
> the models today and found the problem.  The proper peak voltage vs.
> coupling graph, even with all the losses, looks like this:
> 
> http://hot-streamer-dot-com/temp/OLTC08-29-01.gif
> 
> Probably exactly what Marco and Antonio would agree with ;-))
> 
> Sorry if I caused any confusion.
> 
> Cheers,
> 
>         Terry
> 
> ====================
> 
> >Hi Antonio, and Marco too,
> >
> >My small coil was designed for auto quenching using these methods.  "Auto
> >quenching" is a big subject I was always going to write up "someday"...  I
> >never did...
> >
> >Here is the "short" explanation...
> >
> >When you consider the losses of Rpri, Rsec, and streamer loading, the coil
> >looses power very quickly.  Subtle sweet spots indicated by the lossless
> >case are swamped by these giant losses.  Lower quenching allows all the
> >primary's energy to be impressed on the secondary in a single burst for
> >maximum secondary voltage.  I looks like a "ball" where the secondary rings
> >up to maximum voltage and then all the system's energy is gone.  There is no
> >second or third notch.  Modeling definitely suggests this is the optimal
> >situation and my small coil is a great performer given it's power.  My work
> >tonight with the OLTC shows that this is a great value for k as well.  It is
> >hard to "see" without actually "being there" or having a nice paper like
> >Marco's to explain it...  But just imagine the coupling is set to pump the
> >maximum voltage into the secondary in one single shot where we trap it
> >before all these nasty looses ruin it.
> >
> >It may seem that high coupling is good, but it tends to restrict the
> >secondary voltage from ringing up to the best value too.  It seems that
> >hitting the secondary with a well planed single burst at lower coupling
> >allows the highest secondary voltage to build up in the "high loss" case.
> >Remember, that a streamer in a 1000 watt coil may be eating 300 watts of
> >power!!  You just "can't" ignore that giant load and it's effects!!
> >
> >I know it is "unpleasant", but you really "need" to consider Rpri, Rsec, and
> >streamer loading in defining the best values for k.  Since there are no
> >closed form equations for the high loss case (or at least they have never
> >been found.  Perhaps a problem for computer math programs like "Maple"), you
> >will have to use iterative computer programs like MicroSim to find the
> effects.
> >
> >"My bad" for never following up on all this before...  But it is a giant
> >subject I never was able to grab hold of and explain properly...
> >
> >Cheers,
> >
> >       Terry
> >
> >
> >At 10:36 PM 8/28/2002 -0300, you wrote:
> >>Tesla list wrote:
> >>>
> >>> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>
> >>>
> >>> Hi All,
> >>>
> >>> I ran various MicroSim models with K going from 0.05 to 0.25 with primary
> >>> resistances of 0.5, 1.5, and 2.5 mOhms.  I found the resulting peak
> >>> secondary voltages:
> >>>
> >>>         http://hot-streamer-dot-com/temp/OLTC08-28-01.gif
> >>>
> >>>         http://hot-streamer-dot-com/temp/OLTC08-28-02.gif
> >>>
> >>> I think the dip in the yellow line at 13 is a mistake in my data.  In the
> >>> low loss (r=0.0005) case you can see the effect of sweet spots above
> k=0.20.
> >>
> >>The results seem strange. Increasing the coupling should always reduce
> >>the loss, increasing the maximum secondary voltage. The sweet spots
> >>don't
> >>make great difference at these levels of coupling. The large increase
> >>observed for low coupling is very strange. Are you sure that
> >>you are measuring the output voltage with both polarities?
> >>
> >>Antonio Carlos M. de Queiroz
> >>