Re: US Power Outages

At 18:15 8/11/96, Dave Farber wrote:
>The avalanche behavior of power systems is still not
>well understood and techniques to prevent such failures are not obvious.
>Same can be said of telephone and computer networks at different levels.

Does somebody here have a pointer to literature on this topic? A system in
which small localized disturbances can amplify, propagate through the
system, leading to catastrophic failure is the worst of all possible
designs. I fail to understand why a system as important as the power grid
would display this type of behavior. Why is the grid negatively dampened?

TIA,


-- Lucky Green <mailto:shamrock@netcom.com> PGP encrypted mail preferred.
   Defeat the Demopublican Unity Party. Vote no on Clinton/Dole in November.
   Vote Harry Browne for President.

>From what I read, this wasn't a "small localized disturbance".  
Apparently, a fire underneath one of the main towers on the CA-OR border 
was the cause of the problem.  Now that may not sound like too much, but 
the lines were carrying at least 3000Mw of electricity, enough "to power 
3-1/2 Seattles for a day" (quote from local newspaper).  My guess is that 
when there is a problem involving that much power with no place to go, 
the safety systems shut everything down to prevent damage.

Zach Babayco

zachb@netcom.com  <----- finger for PGP public key
http://www.geocities.com/SiliconValley/Park/4127


On Sun, 11 Aug 1996, Lucky Green wrote:

> At 18:15 8/11/96, Dave Farber wrote:
> >The avalanche behavior of power systems is still not
> >well understood and techniques to prevent such failures are not obvious.
> >Same can be said of telephone and computer networks at different levels.
> 
> Does somebody here have a pointer to literature on this topic? A system in
> which small localized disturbances can amplify, propagate through the
> system, leading to catastrophic failure is the worst of all possible
> designs. I fail to understand why a system as important as the power grid
> would display this type of behavior. Why is the grid negatively dampened?
>

-----BEGIN PGP SIGNED MESSAGE-----

In article <Pine.3.89.9608112235.A16390-0100000@netcom3>,
Z.B. <zachb@netcom.com> wrote:
>Now that may not sound like too much, but 
>the lines were carrying at least 3000Mw of electricity, enough "to power 
>3-1/2 Seattles for a day" (quote from local newspaper).

<GRUMBLE>
Watts are a measure of energy per unit time; it makes sense to say
"60 W powers a light bulb", not "60 W powers a light bulb for one hour".
</GRUMBLE>

But my _favourite_ example of this was a newspaper clipping I used to have
that said that in the previous month, the city had received "160 square
pounds of rain".   That just defied common sense.

   - Ian "closely followed by temperatures 'doubling' (which happens more
          often when they use Celcius)"

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Well, all I remember is the 3-1/2 Seattles part - I put the"for a day" 
part in because I wasn't sure about it.  


Zach Babayco

zachb@netcom.com  <----- finger for PGP public key
http://www.geocities.com/SiliconValley/Park/4127


On 12 Aug 1996, Ian Goldberg wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> 
> <GRUMBLE>
> Watts are a measure of energy per unit time; it makes sense to say
> "60 W powers a light bulb", not "60 W powers a light bulb for one hour".
> </GRUMBLE>
> 
> But my _favourite_ example of this was a newspaper clipping I used to have
> that said that in the previous month, the city had received "160 square
> pounds of rain".   That just defied common sense.
>