RE: Fwd: [jlnlabs] TESLA COIL REVISED

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

Original poster: "John H. Couture" <couturejh-at-mgte-dot-com> 


Dan -

You are correct the Cp/Cs and Ls/Lp ratios are identical if the TC is in
tune.
I said the ratios and should of said the impedances are different.  When the
input wattage is the same and the ratios are changed the impedances change
and the currents change. The losses also change and so does the overall
efficiency. The goal of the TC designer is to find the optimum conditions in
the above changes so the overall efficiency is the highest.

If the toroid is increased in size the capacitance ratio and the inductive
ratio are both decreased. However, the primary current is decreased but the
secondary current is increased. The opposite happens if the toroid is made
smaller. These curves gives us an opportunity to find optimum conditions. I
don't believe these optimum conditions have ever been found for any Tesla
coil.

John Couture

--------------------------------------


-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Tuesday, January 06, 2004 9:58 AM
To: tesla-at-pupman-dot-com
Subject: Re: Fwd: [jlnlabs] TESLA COIL REVISED


Original poster: dhmccauley-at-spacecatlighting-dot-com

John,

I believe the Cp/Cs and Ls/Lp ratios are identical.

In a "tuned" classic tesla coil, the design parameter is that Cp*Lp=Cs*Ls

If you play with that equation, you'll find the gain equations using Cp/Cs
and Ls/Lp are identical as Cp and Cs will
vary with Lp and Ls to maintain the tuned design parameter Cp*Lp=Cs*Ls.

Dan


  > Ed, Dan -
  >
  > This is a typical unsolved (?) Tesla coil problem. Which ratio, Cp/Cs or
  > Ls/Lp do you use to find  the true spark (gain) when the input wattage is
  > the same? The other effective spark length parameter in the TC is the
  > overall efficiency. What capacitive or inductive ratios give the best
  > overall efficiencies? This would depend on the complex wave currents
which
  > are different for a capacitive load compared to a inductive load. The
  > question is which ratio gives the best efficiency the optimum capacitive
  > ratio or the optimum inductive ratio? It is relatively easy to adjust
either
  > ratio for a tuned system. To my knowledge this type of question has never
  > been answered for Tesla coils.
  >
  >     John Couture
  >
  > ----------------------------
  >
  >
  > -----Original Message-----
  > From: Tesla list [mailto:tesla-at-pupman-dot-com]
  > Sent: Saturday, January 03, 2004 10:12 PM
  > To: tesla-at-pupman-dot-com
  > Subject: Re: Fwd: [jlnlabs] TESLA COIL REVISED6
  >
  >
  > Original poster: Ed Phillips <evp-at-pacbell-dot-net>
  >
  > "By reducing the number of turns in your secondary, you are reducing the
  > inductance.  Maintaining a constant primary side of your coil, you will
  > need
  > to increase
  > the topload of your secondary to maintain resonance.  Now since GAIN =
  > SQRT
  > (C1/C2) it is fairly obvious that by increasing C2 you are decreasing
  > the
  > maximum
  > theoretical gain of your secondary.
  >
  > Dan"
  >
  > Note that, if both primary and secondary are in tune, the secondary to
  > primary inductance ratio can be used instead.  However, since the energy
  > in the secondary was stored in the primary CAPACITOR before the gap
  > fired, I prefer to think in terms of the capacitance ratio.
  >
  > Ed
  >