[Lowfer] Re: Power Outages

[Costas Krallis SV1XV]

At 11:22 19/08/2003 +0200, you wrote:

> Yes, but there must surely be somewhere a frequency control device.
> The system cannot be self-sustained, just relying on the fact that each
> generator is kept in sync solely by its connection to a power grid
> with energy at 50 or 60 Hz. Somewhere something must have set that
> frequency at 50 or 60 Hz.
> Who controls the frequency and how ?

Well, not really. The actual frequency varies by as much as plus or
minus 1% in most networks. When the demand is high, our grid runs
at about 49.5 Hz. I have repeatedly measured even lower frequencies,
although our utility would not admit it. Now if the demand is
low, the frequency would be somewhat over 50 Hz, but in this case
they would shut down some plants, so it never happens.

BTW I noticed that you are in Italy. Out national grids are
interconnected with a DC underwater link crossing the Otranto
strait. At each end there are power thyristors which convert
DC to AC and vice versa, eliminating any need for frequency
synchronization.

73 Costas SV1XV