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Re: Skin Effect... and More(croft
Subject: Re: Skin Effect... and More(croft
Date: Mon, 28 Apr 1997 21:57:12 +0500
From: "Alfred A. Skrocki" <alfred.skrocki-at-cybernetworking-dot-com>
To: Tesla List <tesla-at-pupman-dot-com>
On Mon, 28 Apr 1997 17:40:06 +1200 Malcolm Watts
<MALCOLM-at-directorate.wnp.ac.nz> wrote;
> > Malcolm, Alfred, and all,
> >
> > There's even more wierdness associated with Skin Effect! It turns out
> > that some current actually does penetrate the conductor's interior. With
> > increasing depth, the magnitude of this current decreases, AND the phase
> > is continually retarded. What this really means is that it's possible
> > that after a certain depth of penetration, current may actually be
> > flowing in a direction OPPOSITE to that on the surface(!). In such a
> > case, the effective AC resistance of the conductor would be decreased by
> > removing the inside part of the conductor - a copper tube will show less
> > AC resistance than a solid copper rod! This effect _actually occurs_ in
> > high current busbars coming off the generators at 60 Hz in big power
> > plants
>
> That is very interesting. I settled on a rule of 3 skin depths for
> secondary wire diameter as it seemed that using much larger copper
> was not only running into diminishing returns resistance-wise but also
> reducing inductance unreasonably. For example, I calculated that a
> total diameter of 8 skin depths was just about the practical limit
> for reducing resistance but using that wire gauge, inductance is
> slashed to around 1/4 of its value. Now it seems from what you are
> saying that one would actually be going backwards by using wire that
> large.
>
> Fascinating post. Any chance a copy of the book could be procured for
> me?
Book? What book?
Sincerely
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Alfred A. Skrocki
alfred.skrocki-at-cybernetworking-dot-com
.ooo0 0ooo.
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