Re: Compulsators 6 million amps of raw power!!!

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

Original poster: "Eddie Burwell by way of Terry Fritz <twftesla-at-uswest-dot-net>" <eburwell-at-HIWAAY-dot-net>

At 06:04 PM 4/5/01 -0600, you wrote:
>Original poster: "Drew Murray by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<drewallmighty-at-hotmail-dot-com>
>
>Hello,
>I have been doing some research on railguns and i heard about something 
>called a compulsator. Do spark gaps have to exist? Can a tesla coil primary 
>tank circuit run on low voltage but at huge amounts of current. 

Depends on what you call low voltage.  Since dI/dt=V/L you need a high
voltage and a small inductance to get a large increase in current with time.
Let's assume you havce formed some copper buss bar into a 16" dia loop. This
has an inductance of about 1uH. If you wanted to hit 6 megaAmps in 10uSec
that would be:

6,000,000A  dI        V
--------- = --- = ----------
0.000,01S   dt    0.000,001H 

from this you can see to get 6MA in 10uSec through a 16" loop you would need
600,000V!

 The discharge of a compulsator into a rail gun is slow by comparison to the
discharge of the cap into the primary of a typical tesla coil. If you could
make a secondary with a resonance of 1KHz or less a compulsator might work ok. 
  A spark gap would cause a large amount of power to be lost in a low
voltage high current circuit. A semiconductor switch would be nice but
insanely expensive since the die area to carry 6MA would be enourmous. One
possibility that comes to mind is a large mercury contactor, although this
would limit your rep rate to maybe a pulse per second or so.


Hope this helps,
Eddie Burwell