Re: OLTC idea...

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Wells,

I was originally thinking of having the primary caps as part of the
inductive loop.  As it "turned out", the caps were brought outside the
loop.  I was afraid that the cap being "part" of the 4500Amp primary may do
something unforseen.  I don't "know" of anything bad, but I didn't want to
take a chance and the thing sort of worked out to what it is now.  I think
Ken's coil may use this for his single loop primary?

Cheers,

	Terry


At 08:30 PM 9/3/2002 -0700, you wrote:
>Hi Terry, all, 
>
>I am writing with a kind of an oddball idea which I had a few years ago,
>and actually made it work on my little desktop coil, and had forgotten
>it completely until today as I was daydreaming...maybe it's a concept
>that would have some use in the OLTC realm, who knows...
>
>Let me first take you back to the heyday of rolled poly caps and Richard
>Quick gaps, about the time when the first little blue boxy-looking phillips
>caps were being soldered together and all the "high power guys" were
>scoffing at the idea of an MMC being used for anything but a little coil...A
>post about rolled poly caps talked about reducing inductance in the rolled
>caps by using strips of foil every turn or two as a terminal, so that
>the charge didn't have to travel around and around the plate to get to
>the terminal. 
>
>well, I got to thinking, what if you could make a cap that had about
>the inducance of a primary, wrapped around a tube which would go around
>the secondary and serve as both the primary and cap in one unit-I think
>I called it a capductor or incapacitator or something, and got some copper
>foil and twisted one up. The way it worked was that each plate had it's
>terminal at opposing ends, so that the charge had to travel in the direction
>that contributed to the magnetic field instead of cancelling it out.
>I wrapped the plate/poly/plate/poly stack around a tube which fit around
>my secondary with about an inch of clearance, and was about 1/3 as high
>as my secondary, with about 8 turns total. The gap and supply went in
>parallel to the "incapacitator", and it resonated with itself. (I know,
>hurts to think about, but basically the inductive properties and the
>capacitive properties produced a unit that resonated at the same frequency
>as my secondary, and served as a primary and cap in one). It actually
>worked! I got the values so close on the first try that I was able to
>tune with 3/4 turn of  refrig. tubing, off axis. 
>
>Anyway, my reasoning was that it would be the lowest loss arrangement
>ever, because the energy wouldn't have to travel out of the capacitor,
>into the primary, and back, but would just be rocking back and forth
>along the plates of the incapacitator. 
>
>I dunno, maybe you could construct a poly and copper plate cap that would
>wrap around the base of the OLTC, and simply connect the IGBT "brick"
>across the leads of the incapacitator? you would have to get the values
>right in designing the thing, but that shouldn't be too hard, I did it
>with wintesla. 
>
>Anyway, just an idea, I thought it was a neat concept at the time, but
>never got much farther than cobble-up. But it was neat seeing "noodle
>theory" turn into reality :>). 
>
>Does this sound like anything you could use?
>
>-- 
>Wells Campbell
>wellscampbell-at-onebox-dot-com
>
> 
>