In message , T i m
writes
On Sun, 11 Oct 2020 21:50:41 +0100, Vir Campestris
wrote:

snip

Frequency - AIUI generate DC, and use some clever electronics to get it
on the grid. Not quite clever enough though...

I think we went to a small power station when I was at college doing
my HND in Electrical Engineering and I think they synched the
frequency of their output to that of the grid manually ... or hit the
big connection switch manually suggesting if they got it wrong by more
than a bit, it could rip the generators off their mounts?

Cheers, T i m

I did a fair amount of 'heavy current' electrical engineering at
university, and one of the lab experiments was to run up a large (and
fairly ancient) three-phase generator (driven by a DC motor) and
synchronise it with the mains.

Not only did you have to get the speed right, but (obviously) you had to
ensure that the three phases were correct. This was achieved by having a
lamp bulb across each of the contacts of the three-pole switch that
connected the three generator armature outputs to the mains. [I believe
the lamps were coloured red, blue and yellow.] As you approached
synchronous speed the fluctuations in their brightness would slow to a
stop - and when the brightness was at a minimum you then had to adjust
the generator field current to get the generator output voltage to
exactly match the mains voltage (when the lamps went out). Only then
could you throw the switch - and if there wasn't a big bang and a
grinding of metal you knew you had got the generator successfully locked
to the mains.

You then did various measurements about (for example) what happened when
you altered the drive power supplied by the DC motor and the amount of
generator field current. Again you had to be careful, because if you
varied things too far the system could unlock from the mains (with the
aforementioned spectacular results).

All this was pretty scary stuff, and these days I expect that the
operation of power stations is far more automated and foolproof than it
used to be.
--
Ian