Re: Equivalent lumped inductance and toroidal coils

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

Original poster: Paul Nicholson <paul-at-abelian.demon.co.uk> 

Gerry wrote:

 > Is this another way of saying differential current elements
 > or is there something different here?

It's a way of representing mutual inductances between
short segments, rather than loops.  I don't really understand
it or know how to implement it.  There's something about it
in some tuturial notes I found in

  http://videos.dac-dot-com/videos/38th/22/22_1/22_1.pdf

(it also mentiones the quasi-static approximation that we use
when modelling TCs, which decouples the E and H fields allowing
us to use inductance and capacitance as a substitute for field
theory).

Antonio wrote:

 > I am thinking about doing "exact" calculations using as
 > core the mutual inductance between two straight segments.

I wonder if that's the same thing as 'partial inductances'?
Maybe it's like equ 9 in the pdf above.  From Rosa, 1908.

The idea seems to be that you break up the network into
segments, work out the partial inductance between each
possible pair, and then the required loop mutual inductance
are produced by simply summing the relevant partial terms
as per equ 8.  Doesn't sound any different, really, to what
we already do with circular filaments.  I expect Antonio will
say it is the same thing that he is doing now with the
Neumann integration.

Often, with these inductance things, I don't really understand
the formulas involved or try to derive them - I just close my
eyes and plug them in to the computer.
--
Paul Nicholson
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