Re: primary solid/ tube and DC TENSION LINES

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

Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-qwest-dot-net>" <evp-at-pacbell-dot-net>

Tesla list wrote:
> 
> The other, probably more important, reason for DC has to do with the
> inductance and capacitance of the long line making the system hard to
> stabilize... with a DC link, one end has a constant current sink and the
> other has a constant voltage source, and it stabilizes itself...  none of
> this horrible stuff with synchronous var compensation, generator
> synchronization, and so forth.
> 
> I have heard that on the Pacific Intertie (a big AC link running on the
> West Coast) it takes upwards of 8-10 hours for the transients to die out.

	When I went to Caltech (long, long ago) a standard problem for an AC
power course was to calculate what happened when the line from Boulder
Dam to Los Angeles was interrupted. We had to do a point-to-point
analysis of the transient which resulted when it was reconnected after
enough time for the turbines at Boulder to pick up speed due to the loss
in load.  Lotsa work in those days, but really simple now.  Stability of
large interconnected systems with many sources and loads is marginal at
best, and maintaining everything synchronized and delivering the right
power is a really big problem these days.

	Something sort of related to power system stability is the problem
associated with connecting a self-excited oscillator to a resonant
load.  Standard situation with a VTTC driven from an oscillator rather
than an amplifier.  Somewhere I have an interesting paper written by a
guy who was involved in the design of the driver circuits for a
cyclotron at UCLA.  The conclusion I drew from it was that using a
master oscillator - power amplifier configuration for a VTTC might
really simplify tuning, but I've never tried it.

Ed