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: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>
 >
 > Hi All,
 >
 > Jay Reed has sent me the following paper:
 >
 > http://hot-streamer-dot-com/temp/DesigningtripleresonanceTeslatransformers.pdf
 >
 > Designing High-Gain Triple Resonance Tesla-Transformers

Interesting. Is this a published paper?
I seems possible to adapt my design procedure to account for a
capacitance across the third coil, but I wonder how to determine
the value of this capacitance, given the dimensions of the coil.
I usually consider that the capacitances of a coil can be modeled
as two capacitances to ground, similar to Medhurst's capacitances,
one at each end of the coil. The "other plate" of a Medhurst
capacitance is the ground, and not the other end of the coil.
Of course some of the electric field ends at the other end of the
coil, but how to determine how to split the Medhurst capacitance
in two parts, one to ground and another to the other end of the
coil?
A possibility would be to model a coil with distributed capacitance
more precisely, by splitting it into a large LC network, as Paul
Nicholson did, and then looking for the first notch in the frequency
response obtained by exciting the coil at one end and looking at
the voltage at the other. A capacitance across the coil can then
model this notch. The capacitance from the output to ground can
be obtained from the first resonance observed, that would be the
resonance frequency of the coil with the two capacitances added.
An identical capacitance, or a somewhat different one, if the
actual geometry of the system is considered, can be obtained by
exciting the network from the output side and observing the input.
There are other details and complications if this extra capacitor
is added, but nothing that can't be treated.

Antonio Carlos M. de Queiroz