Re: Bipolar capacitive transformer/transformerless TC

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

Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <teslalist-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:

 > Original poster: "Jolyon Vater Cox by way of Terry Fritz 
<teslalist-at-qwest-dot-net>" <jolyon-at-vatercox.freeserve.co.uk>
 >
 > I would be interested to know whether the topology below would be any use
 > in building either a bipolar "capacitive transformer" TC or
 > (with the capacitors C2a and C2b replaced with two inductors both equal to
 > half the total inductance of L2) a bipolar "transformerless" TC.
 >...

Attempts to use ideal transformers don't work, since they would have
to have too high inductances and unity coupling. With real
transformers, or uncoupled inductors, the two halves are different,
and it's not possible to design your circuit (if possible at all) from
the values or an unbalanced prototype.

A bipolar transformerless coil with capacitive coupling can be:

o--+----2C1----+----2C2---+---+
    |           |          |   |
   gap          L1         L2  C3
    |           |          |   |
o--+----2C1----+----2C2---+---+

or, easier to build, but dangerous (60 Hz at the induction
planes):

o--+----L1/2----+----2C2---+---+
    |            |          |   |
   gap           C1         L2  C3
    |            |          |   |
o--+----L1/2----+----2C2---+---+

The values come from the capacitive transformer coil. L2 would be a
suspended resonator coil with influence planes (forming the
capacitances 2C2 with it) at both ends. C3 is formed by the remaining
capacitance across L2.

With direct coupling, the circuit would need two uncoupled
resonators:

o--+----2C1----+----L2/2---+
    |           |           |
   gap          L1          C2
    |           |           |
o--+----2C1----+----L2/2---+

or (very dangerous due to 60 Hz at the output):

o--+----L1/2----+----L2/2---+
    |            |           |
   gap           C1          C2
    |            |           |
o--+----L1/2----+----L2/2---+

C2 is the series association of the self-capacitances of the
resonators, with some extra capacitance due to the terminals
and the spark gap that may be added between them. The element
values come from the unbalanced design.

A more efficient system can be in the form of a balanced
transformerless magnifier with a capacitive transformer
at the end:

o--+----2C1----+---L2/2---+---2C3---+---+
    |           |          |         |   |
   gap          L1         C2        L3  C4
    |           |          |         |   |
o--+----2C1----+---L2/2---+---2C3---+---+

or, with two capacitive transformers:

o--+----2C1----+---2C2---+---2C3---+---+
    |           |         |         |   |
   gap          L1        L2        L3  C4
    |           |         |         |   |
o--+----2C1----+---2C2---+---2C3---+---+

All the prototypes can be designed with the program mreshp, at:
http://www.coe.ufrj.br/~acmq/programs.

I will have to set up a web page with my comments on Jolyon's ideas.
A lot of circuits already.

Antonio Carlos M. de Queiroz