high voltage

[raburgeson]

I ran into a snag on my low voltage source and am going to try a large battery charger with a good
boost on it.Flybacks are to weak.We have to figure out a cheap way to get above 300 KV, that of course
doesn't wiegh to much.I'm trying to run ignition coils in parallel and have had some limited success but
the isolation caps between the coils have been arcing between the terminals.Maybe if I make cathodes
and anodes half ellipical  shaped to reduce arcing at the edges and also it wouild move to temrinals farther
apart.(just becase of the shape of the plates)  What do you guys think?

Things are looking up in some other areas though I got a new 8.5 hp motor from Northwestern,
and a 100 amp alternator off an old school bus at the junk yard - that was a good find. I,ve
heard that firetrucks have a better alternator but none of the scrap yards here have one, go
figure.

[betajim]

Hi,

Achieving 300 kV is going to be hard, especially with ignition coils. There are two ways I
would go to get that high a voltage: 1) use a Van de Graff type generator, this has the
advantage of supplying a DC current. 2) find some high voltage step-up transformers of
the type used in high voltage power transmission, the down side is they won't be cheap
even if they could be found surplus.

Are looking to generate 300kV AC or DC?

[Dinorben]

I'm no EHT expert but I wonder if a long voltage doubler circuit might be a better option than trying to stack coils?

But either way, with 300kV I guess the  main problem is going to be insulation - a 20 kV discharge will arc about 10 mm through dry air, but the same discharge can travel over 20mm along a clean surface, and at your target voltage I guess you have to multiply those distances by 15  

Insulating materials perform much better than  air - I wonder if keeping the entire unit potted in wax would help? Even so, at 300kV you might have to resort to using porcelain or even glass insulation immediately adjacent to the conductors.

Dinorben

[raburgeson]

Insulation is a big problem,and I've had companies sell me supposably new materials that are
high quality that has turned out to be recycled bull feeces. I have learned how to test
insulation by throwing some into the microwave and watch for sparks , if it's recycled crap
you will see sparks.

[raburgeson]

Midsun and Sylguard seem to be the best 2 sorry hit the wroung  key and sent post to
early.