Re: this was probably really stupid

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

Original poster: Jim Lux <jimlux-at-earthlink-dot-net> 

At 05:35 PM 5/27/2004 -0600, you wrote:
>Original poster: Ed Phillips <evp-at-pacbell-dot-net>
>"As Ed mentioned, it's all in the bundling.  Bundling also reduces
>inductance (which is a BIG deal for long distance high power
>transmission
>lines.. it makes the system hard to stabilize), and reduces skin effect
>losses.  All in all, bundling is a "good thing".  Around here (southern
>CA), you see a lot of two conductor bundles (probably on the 138 or
>345kV
>lines), but occasionally 3 or 4 conductor bundles.  Looking at some
>photos
>of the "Path 15 improvement" project, it looks like they are 3 wire
>bundles
>(Path 15 is a 500kV line)
>http://www.wapa.gov/media/cct/2004/may14/26no102a.htm
>
>I found a picture of a DWP line claimed to be 750kV DC that looks like a
>dual bundle.  However, I always thought that line ran at 500kV (maybe
>it's
>a voltage to ground vs voltage between conductors issue)"
>
>         The conductors on the DC line you mension do consist of two 
> "wires" in
>parallel, at least in the one place I could get out of my car and look
>at them with binoculars.  I'd guess the spacing is of the order of a
>foot and merely that the conductor diameter is much smaller.  A common
>way of speaking of that intertie is "1.5 MV line to line", but that
>doesn't prove the actual voltage, which might actually be varied
>depending on the load.


And, of course, it might be 750 kV at the northern (source) end and 
somewhat less at the southern (load) end.  Although I can't imagine the 
difference would be THAT big... maybe 5% loss overall? And, of course there 
will be transients running up and down that wire as they change the power flow.

I seem to recall that one end is constant voltage and the other is constant 
current, which is how they control it.  All very clever and none of that 
phase shifting and synchronous VAR generator stuff.