Joel Kolstad wrote:
"Joel Kolstad" wrote in message
...

For some of the university work I've done, some of our reference papers are
from people modeling power lines as full-fledged transmission lines that are
many wavelengths long at 50Hz. No simple equivalent circuit model works for
them either!


OK, I did get a little over-excited there -- it should say "that are
significant fractions of a wavelength long," (e.g., more than 1/6th) such that
you can't use a simple circuit model for them.


That's interesting -- SPICE has models for (lossless) transmission
lines, and lines of that length can also be adequately modeled with a
few LC sections. I can imagine line loss could be tricky, though. I've
modeled skin effect loss in the process of designing time-domain
circuits to compensate for delay line loss over a wide time range (and
therefore broad frequency range). But loss due to interaction of the
fields with ground underneath the wires might be more difficult. At
least you've only got one frequency to deal with -- unless harmonic
content is high enough to worry about. Perhaps you've also got to deal
with loss due to radiation?

Roy Lewallen, W7EL