Re: charge reactors

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "S&JY" <youngsters@xxxxxxxxxxxxxxx>

Deano & all,

I have also tried this, and it works well.  BUT, as you say, it requires
rather large DC reservoir (filter) caps which are very scary and lethal
things.  I once tried using triggered spark gaps instead of a RSG, but, like
IGBT H-bridges, it was succeptable to "shoot-through" (gaps fired directly
across energy storage caps), resulting in tremendously loud, heart
palpatating BANGS!  Using large filter caps at many KV was so scary that I
sold mine & moved on to the tamer method, below.

The H-bridge RSG is also much more complicated and more lossy.  Mine had 8
gaps total that would fire at each presentation.  There was another person
who first posted regarding his H-bridge setup years ago.  He later used a
resonant charging method with his H-bridge.

--Steve Y.

----- Original Message -----
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Sunday, October 08, 2006 12:46 PM
Subject: Re: charge reactors


> Original poster: David Dean <deano@xxxxxxxxxxxxxxxx>
>
> hi
>
> or you could try this
> http://www.pupman.com/listarchives/2001/July/msg01383.html
>
> or-
> An H-bridge rotary arrangement along the same lines that will charge the
tank
> cap to twice the power supply voltage on second and subsequent bangs as
well
> as eliminating the need for a charging reactor. Though the power supply is
in
> the circuit during the bang, the gap quenches when the tank cap is charged
to
> its level. At the next presentation the power supply voltage is presented
to
> the tank circuit with the same potential but opposite polarity.
>
> Of course I have not tried this, and it may have unforseen problems, but
then
> again it just might work. It would be very important that the energy
storage
> cap be >> than the tank cap and rated for pulse duty.
>
> later
> deano
>
> P.S.  a quick and dirty diagram @
>   http://deanostoybox.com/temp/schem.jpg
>
>
> On Saturday 07 October 2006 22:48, you wrote:
>  > Original poster: "S&JY" <youngsters@xxxxxxxxxxxxxxx>
>  >
>  > Earl,
>  >
>  > I have used 4 MOT secondaries in series for a DC resonant charging
reactor.
>  > Of course, they need to be mounted on insulators and spaced apart, but
they
>  > don't need to be submerged in oil.  The MOTs work fine with no airgap
as
>  > long as you stay above the minimum break rate to avoid trailing arcs in
>  > your RSG.
>  >
>  > There is another way to run a DC resonant charging coil that avoids the
>  > need for the large iron core reactor altogether.  Instead, it just uses
a
>  > small, easily built air core reactor.  It does require an extra set of
gaps
>  > on your rotary spark gap.  The power supply resonant charges the MMC
>  > through one set of gaps, then discharges the MMC into the secondary
with
>  > the other set of gaps.  This works wonderfully well, allowing break
rates
>  > as low as you want with no risk of destructive trailing arcs, and
>  > effectively disconnects the power supply during the main bang.
>  >
>  > Contact me off list if you want more details on the alternate method.
>  > --Steve Y.