Re: transferring electrical energy through metal wall

Well it seems to me that the best answer is actually a compromise (or
a combination) of some of the other answers you have received so far.

1) Several people suggested high pressure feedthroughs (I agree)

2) You said that the parts receiving the energy inside the pressure
vessle must move (I take it they will rotate continuously?) and
therefore wires are not paractical (and for that matter I don't think
brushes are practical either since you will be operating the device in
a high pressure environment.)

so you feel that some sort of inductive coupling of the energy to the
moving parts is required. (Once again I agree)

So the answer is to put both your primary and your secondary on the
inside of the device and to power the primary via the high pressure
feed through and allow the secondary to move relative to the primary
to accomidate your necessary movement.

It sounds an awful lot like you are going to test a deepwater
submersible motor to me? Unless you are going to use a high pressure
gas?

This plan allows you to accomidate both the high pressure and still
have high electromagnetic conversion efficiency because you don't have
to resort to turning a bulkhead wall into a crappy transformer core.

Use a better and much more standard transformer/motor design instead.

Although this solution still avoids the basic problem of how to pass a
large amount of energy through a solid ferrous wall with resonable
efficiency and not drill holes?

That in it'self is an interesting question and I suggest that the
discussion  continue on that problem.

Perhaps you could do it with with X-rays? I don't think so but I could
be wrong?

Thanks: Steve Ivy