Hi John,
Using unbalanced HV (or medium voltage) power distribution seems to be a
new thing here in the USA. I have been looking at power lines as long as
I can remember, and the use of one hot lead and one grounded lead for
the distribution on the primary side of the pole pig transformers is
something I have only seen in the last several years. Anyway I think the
biggest problem is going to be the secondary side 120/240 volt
distribution which as untold multitudes of different loads connected to
it, with an incredible variety of reactances caused by all the stuff
people plug into their power outlets. These lines will never be
balanced, and the BPL currents in them will never be balanced. So these
lines will be antennas NOT transmission lines. On the other hand the
primary distribution will have a better chance of acheiving balanced
currents (where balanced instead of single ended circuits are still in
use), however these lines have spacing that is too great to be a
transmission line for HF. They will also be antennas.
DE N6KB
John T. Fleming wrote:
The aspect that I have not seen mentioned when comparing the US power system
to the foreign power systems is the use of 3-phase by most foreign
countries. The lines run parallel and tend to cancel each other like an
antenna with open line feed. In the US, we generally work against "ground"
and the transmission wire will look like an antenna.
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