OLTC - Split core inductors

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

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

Hi All,

I have been learning a whole lot more about inductors than I ever wanted to
know :-p

A closed iron inductor that can take about 5 amps, 120Hz, 150mH, and 3 ohms
DC resistance would be very large due to saturation (also has those odd
non-linearities).  The inductor should not be over 3 ohms of DC resistance
since it hurts the resonant charging (5 amps at 3 ohms is also 75 watts!):

http://hot-streamer-dot-com/temp/OLTC08-16-05.gif

So I looked at air core inductors using the information at this nice site:

http://www.ee.surrey.ac.uk/Workshop/advice/coils/air_coils.html

I did a lot of math and Excel stuff and came up with this list of
"possibilities":

http://hot-streamer-dot-com/temp/OLTC08-16-06.gif

It is based off the needed inductance, resistance, and wire data.

There are no practical solutions!!  For example a #12 wire coil 13.5 inches
in diameter with 2300 feet of wire at 60 pounds!!

The spreadsheet is here if anyone cares:

http://hot-streamer-dot-com/temp/airwire%20chart.xls

So we are looking at a big split core inductor like my split variac core:

http://hot-streamer-dot-com/temp/OLTC8150009.jpg

It measures 47mH so I need SQRT(150/47) = 1.79 as many turns on it.  Very
possible...  It is only 0.4 ohms DC resistance right now and it has
excellent V/I and inductor characteristics.  I am sure a MOT core or any
big iron core be used too.  Sad, we need iron, but the H*** with it ;-))
It really only weighs 3 pounds 14 onces...  More research later will be
need into these inductors and figuring out how to make them easy for anyone
to reproduce.  Now I know why my request for ideas on inductors went
unanswered ;-))  I ain't easy...

I also got the caps today from Richardson electronics.  Took three weeks
and I didn't know if they were ever really going to come, but they did.
Chris was also getting caps for me :-|  No worries, I think we can find a
use for them in the higher power version :-))

Much construction work to do...

Cheers,

	Terry