Re: OLTC - Primer

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

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

Hi Malcolm,

At 04:01 PM 8/15/2002 +1200, you wrote:
>Hi Terry,
>          I'd be tempted to run a sim with a 500nH inductor and 47uF 
>and see just how low total primary AC resistance has to go to score a 
>Q of 10 or so (typical of a half decent SG coil) at your proposed 
>operating frequency.
>
>Regards,
>malcolm
>

We have a cap, IGBT array, and a primary coil.

The cap specs are, for ten in Parallel (done well), 0.4 mOhms (0.0004)
3.8nH.  The IGBTs have an effective resistance of about 0.001 ohms!!

The primary coil is 14 inches in diameter of three parallel 1/2 inch copper
tubes:

http://hot-streamer-dot-com/temp/P8140005.jpg

F0 = 33kHz.

So we are dealing with "really small" impedances here :-))  It seems crazy
passing such low (500V) through such low impedances (milliohms) to get
oscillation, but that is what this thing is about...  We are looking at
3000-5000 amp peak primary currents too!

Sounds "odd", but no HV tranny and no variacs...  A very different machine
indeed ;-))

Hehehehehe!!

Cheers,

	Terry