Brian Gaff wrote:

Yes well I have no real idea how all generating gear can be synchronised
either. Seems a trifle crude but then I guess getting it wrong could be
rather nasty, so how is it done when they import power from other countries,
how do they go about deciding who needs to synchronise to whom?

You either have a fully synchronised grid covering a continent (remember
how serbia/kosovo were causing all european mains to run slow a wile back?)

Or you link them using HVDC, and then you don't need to sync.