Montana St Alum wrote: ↑Fri Feb 19, 2021 2:56 pm
Early in my airline career I was a flight engineer. Combining 3 generators, one from each engine, wasn't terribly difficult, but it had to be done manually at the time. And that's a simple combination.
I know a thing or two about sparky-go-spark. Paralleling 3 generators is pretty easy. If you manually did it, most likely they were of the same capacity. So just adjust the governors to make load sharing equal across all three.
Paralleling generators of different capacity is not impossible manually, of course, but load sharing gets to be tricky.
Whatever electrical plant you were in charge of had a specific amount of rotational mass. So, when bringing a new generator on the line, these rotational masses “adjust” at the moment the breaker is closed, the rotating fields are synchronized when hard wired together. If you do it correctly, with the synchroscope rotating “slowly in the fast direction”, and when the synchroscope is immediately before 12 o’clock position (or synchro lights are just extinguished, for the really old plants), the you won’t hardly notice anything. If you perform the procedure out of spec a little, can notice some vibration, which is wear and tear on all associated machinery.
Now, imagine the aggregate rotational mass of the steam turbines/ gas turbines on the West coast, and East coast, and Texas having to adjust to each other simultaneously. That adjustment will cause issues... like bearing failure issues, like catastrophic eddy currents on the bus bars issues.
Really, the only way to unify the country to one grid would be to pick a grid (maybe East Coast) as parent grid. All other generators on all other grids be taken offline. Then one generator on West coast grid is synchronized with East coast grid. Then, all other West coast generators are synchronized to the West Coast grid.
It’s not impossible, but takes a lot of coordination, a lot of broken rice bowls, and a lot of broken egos because there will be only one master. Additionally, reducing quantity of wide area grids for the country has a huge impact to the Failure Mode Effects Analysis (FMEA) for the country’s electrical redundancy. Currently, the failure mode for the entire country is actually protected by using separate grids. So, a huge undertaking in mitigating these extra risks would have to be implemented to maintain the same level of redundancy / battle hardening / etc.
Nothing is impossible. I foresee these discussions becoming much more relevant in the next decade or two.