More three phase fun...

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Jim Lux" <jimlux@xxxxxxxxxxxxx>

OK.. here's another idea.

You want a BIG coil, drawing a bunch o' power (say, 10kVA +)

you want to run off three phase (so you can use primary side chokes and
resonant charging)

You want to be reasonably portable (as in, it can be towed behind a
reasonable sized SUV)

You don't want to fool with all sorts of idler motors, big boxes of
capacitors and such like to draw the 10kVA from your single phase service at
home (although, 10kVA is only 40A from the 240V service)

You want to "own" the gear, as opposed to renting a big generator each time
you play with the coil.


Get 3 inexpensive gasoline powered generators... (e.g. Coleman power mate
3750W @ 249 from PepBoys, etc.)
http://www.colemanpowermate.com/generators/pm0523202_17.shtml

Run them in parallel, phased 120 degrees apart.

Now... you're going to say, How in the world do you do that??
I'm not sure, yet, but I suspect you can do it the same way you can parallel
two generators.. You start them both, measure the relative phase (connect
the "neutral" on both, put a lightbulb between the "hot", and adjust the
speeds until the lightbulb stays out) and adjust until in phase, then
connect the two together, after which, they'll remain locked (except for
some potential problems with resonance, governor mismatches, etc.)

So, I think, if you had some sort of "three phase" intertie (a smallish
zigzag transformer, or even a small three phase motor), you could do this.
The key is the intertie.. if one generator slows down a bit (retarding the
phase), then it needs to draw less power, so it can catch up.

Yes, these cheap generators are just that... cheap, noisy, etc.  However,
you're running a big (presumably noisy) tesla coil with them. They're also
heavy!  100 pounds each.

I recognize that a "better" solution is probably to get a surplus 20kVA 3
phase genset.