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Re: DC TC
Tesla List wrote:
>
> Original Poster: "Ruud de Graaf" <rdegraaf-at-daxis.nl>
>
> >> I suspect that adding the diodes prevented some of the energy that was
> >> left in the tank capacitor from flowing "back" into the transformer's
> >> leakage inductance during every AC voltage zero-crossing. The
> >> bidirectional energy transfer that normally occurs between the tank cap
> >> and the leakage inductance of an NST (even for non-resonant charging
> >> systems) was prevented by presence of the diodes. This would have the
> >> impact of reducing the overall efficiency of energy transfer between the
> >> NST and the tank cap, reducing performance.
> >>
> >> Safe coilin' to you!
> >>
> >> -- Bert --
> >>
>
> Hi Bert,
>
> The way I see it, the energy of the primary cap should go to primary coil,
> not back to the secondary power supply! Performance is the ratio Pout/Pin.
> 'The bidirectional energy transfer' you are talking about is loss, so the
> diode(s) should improve things in my opinion. Of course I have not so many
> experience with TC's, so excuse me if I am totally wrong with this theory.
>
> Ruud de Graaf
> Greetings from sunny Holland
Ruud and all,
It turns out that the leakage inductance of the NST and the tank cap
will tend to exchange energy rather than dissipating it. Under some
conditions, the capacitor will actually transfer energy BACK into the
NST leakage inductance (if not blocked by the diodes). This exchange
makes for a more efficient overall transfer of energy between the NST
and the tank cap on the NEXT mains half-cycle. Rather than attempting to
fully explain the theory, I'll instead refer you to the excellent
explanations provided by Richie Burnett regarding inductive ballasting
(which includes NST's), resonant charging, and inductive "kick" effects
- check out the following sections of Richie's site:
Inductive Ballasting Theory:
http://www.staff.ncl.ac.uk/r.e.burnett/ballast.html#inductive
Resonant Charging:
http://www.staff.ncl.ac.uk/r.e.burnett/resonant.html#resonant
Larger Than Resonant Charging - the Inductive Kick effect
http://www.staff.ncl.ac.uk/r.e.burnett/indkick.html#kick
Kinda' heavy stuff... but it actually works! Safe coiling to you, Ruud!
-- Bert --