Re: Proposed DC Drive

To: tesla-at-pupman-dot-com
Subject: Re: Proposed DC Drive
From: Tesla List <mod1-at-pupman-dot-com>
Date: Wed, 8 Oct 1997 12:59:29 -0600 (MDT)
Approved: mod1-at-poodle.pupman-dot-com


---------- Forwarded message ----------
Date: Wed, 08 Oct 1997 06:20:20 -0700
From: Bert Hickman <bert.hickman-at-aquila-dot-com>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Proposed DC Drive

Tesla List wrote:
> 
> ---------- Forwarded message ----------
> Date: Wed, 8 Oct 97 03:54:51 UT
> From: Larry Robertson <LWRobertson-at-classic.msn-dot-com>
> To: Tesla Builders <tesla-at-pupman-dot-com>
> Subject: Proposed DC Drive
> 
> >---------- Forwarded message ----------
> >Date: Tue, 07 Oct 1997 11:50:19 +0000
> >From: Greg Leyh <lod-at-pacbell-dot-net>
> >To: Tesla List <tesla-at-pupman-dot-com>
> >Subject: Re: DC drive
> 
> --  Snip ---
> 
> >Interesting idea!  My only concerns would be:
> 
> >Can the storage cap handle the high RF currents?  It must,
> >since adding a decoupling cap to it would defeat the whole
> >purpose of the storage cap.
> 
> >The RF filter will have to be heavy duty.
> 
> >Also, the gap doesn't have to reverse the polarity to
> >achieve the same effect.  The energy per pulse is the same,
> >whether you run the resonance caps at +15 or -15kV.
> 
> >-GL
> 
> That diagram is alot clearer if you draw it on paper.
> 
> I think at the instant the gaps fire, the primary coil will see
> 30 kV - the 15kV in the resonance cap, added to the 15 kV in
> the storage cap. The voltage in the storage cap wouldn't
> change much per pulse since it's capacitance is 100 times bigger.
> The voltage in the resonance cap, however, would change polarity,
> from +15kV to -15kV without ever stopping at zero.
> 
> I haven't the foggiest clue how dwell time and resonant rise
> will change the picture, but we should have a working model
> later this month to put all these theories to the test.
> 
> If I'm not missing something vital - always a possibility - doubling
> the voltage to the primary ought to quadruple the energy input.
> E=1/2 C(V squared) I seem to recall.
> 
> Anyhow I guess we are staggering around in unknown, but not
> unknowable territory.
> 
> LR

Larry,

The circuit ought to work in a fashion similar to having a single tank
cap charged to 30 KV. Stresses on the tank cap will be quite large since
the DC swing is 30 KV, and the AC excursion is minimally 45 KV. The tank
cap should be rated for at least 90 - 100 KV if you're really going to
run 30 KV rail-to-rail. Because of the interesting "surprises" you'll
undoubtedly encounter, you may want to start out with somewhat lower
rail voltages and work your way up to the 15 KV level! This looks very
similar to the circuit in the current issue of TCBA. Good luck!!

-- Bert --