On Sun, 2011-05-08 at 09:40 -0400, Carl Denk wrote:
> Far from an expert in this area, but: I heard something recently, that=20
> once that switch was thrown to bring the generator online to the grid,=20
> the the electromagnetic forces took over. If the generator was trying to=
=20
> run too fast (governor set higher RPM), the load increased slowing the=20
> generator and bringing into phase, and if too slow, then the load was=20
> lessened and speed increased. There is probably a better explanation of=20
> the phenomena. The main generating station compares the clock to a=20
> standard time piece, and adjusts their speed to provide us with correct=20
> time within a second or so.

That's correct.

In my 3rd (or 4th, can't remember) power electronics course we actually
did that. We had a setup where we had a motor turning a generator with a
light bulb between it and the grid. Our aim was to adjust the motor
speed so that the light bulb remained as close to "off" as possible
(constant mean we'd matched frequency, off meant we'd matched phase).
Once we were close we'd throw the switch and the generator would be on
the grid.

Some students didn't really understand how things worked, lab time was
ending and they still hadn't gotten their generator on the grid. In an
act of desperation, despite their lightbulb blinking quite quickly they
threw their switch.

A huge thud, and breakers blowing were the only things heard in the
room.

Very "real" way to learn about these things! :)

TTYL

--=20
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