Re: Designing High-Gain Triple Resonance Tesla-Transformers

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

Original poster: "Antonio Carlos M. de Queiroz" <acmdq-at-uol-dot-com.br> 

Tesla list wrote:
 >
 > Original poster: "Steve Conner" <steve.conner-at-optosci-dot-com>
 >
 >  >Jay Reed has sent me the following paper:
 >
 > Very interesting.. But it seems from the voltage plots (figs. 3 and 4) that
 > his "optimized" design does not have complete energy transfer, since V2
 > doesn't drop to zero when V1 peaks. Compare to the plot for Bienosiek's
 > design, fig. 3, where v1 _does_ drop to zero.
 >
 > Maybe Reed's design is optimised for voltage gain only, and not energy
 > transfer. But I would have thought that improving the energy transfer would
 > increase the voltage gain too, and hence a coil with optimal voltage gain
 > should automatically have 100% transfer.

Apparently he is trying to find a solution similar to what can be done
in
a Tesla coil, by increasing the input capacitor and readjusting the
coupling coefficient (not changing the coils), while keeping the mode.
This can result in a small increase in the voltage gain, at the expense
of incomplete energy transfer. Of course, if the coils are redesigned,
with the same input capacitor complete energy transfer is again
possible,
with still higher gain.
I find strange that the author apparently doesn't realize that with
a transformer any voltage gain can be obtained, in design at least.
So, comparisons with designs with other gains doesn't make sense.
I tried to work an analytical solution for this problem, but so far
didn't obtain anything simple. I tried too numerical optimization, but
much to my surprise the optimizer finds a solution, changing the mode,
that results in higher gain than the solution that keeps the mode.
(See the optmag program in http://www.coe.ufrj.br/~acmq/programs).
The 1:2:3 mode, for example:
The coupling coefficient for the complete energy transfer case is
0.6742.
Multiplying C1 by 2.134 and changing the coupling coefficient to 0.7156,
the voltage gain is multiplied by 1.21 at the second output peak.
It's possible to obtain even more, but several peaks away.

Antonio Carlos M. de Queiroz