Re: A 20 kV DC tank supply

To: tesla-at-pupman-dot-com
Subject: Re: A 20 kV DC tank supply
From: Greg Leyh <lod-at-pacbell-dot-net> (by way of Terry Fritz <twf-at-verinet-dot-com>)
Date: Sat, 12 Dec 1998 22:50:53 -0700
Approved: twf-at-verinet-dot-com

> Original Poster: "D.C. Cox" <DR.RESONANCE-at-next-wave-dot-net>
> 
> to: Marco
> 
>  As long as you can recharge the caps fast enough your idea will work.
> Many times, with a straight AC supply, the recharge rate for full charge in
> the caps is not fast enough and the RSG fires at less than full charge.
> This produces the thinner streamer type sparks I was referring to.  This is
> especially true for large systems running large caps.  Still, you might
> have trouble with the diodes as Greg Leyh did during his initial testing.


?????
I don't know to what trouble you are referring -- the diodes were 
one of the most trouble free parts of the system!  The rotary gap 
was the biggest troublemaker, BY FAR.  *None* of the diodes in 
Electrum's resonant charger have ever failed during the operation 
of the coil!

The only time I've ever lost a diode was during a test of the DC 
power supply, where a wiring error caused 76kVAC to be accidentally 
applied across a 50kV stack -- and even then only one stack out of 
the six total was damaged.  During normal operation of the resonant 
charger the diodes perform to specification.

I should also point out that DC resonant chargers are the standard 
method for charging caps in high rep-rate, high reliability applications 
such as radars and even linear accelerators.  There are 243 150kW class
DCRC's in service along the SLAC accelerator, and they run 24hr/day 
at 180BPS.  The resonant charger topology has been around longer than 
I have, which makes it all the more interesting that no one else has
applied the concept to Tesla Coils (especially coilers named DC! :^)
-- 


-GL
www.lod-dot-org