In addition to the article on the grid, this link includes a video on how to 'flash' a home generator to make it produce power -[Excerpts]
The now-fabled “February Freeze” left millions, mostly in Texas, scrabbling about in the dark and cold as a series of cascading engineering failures took apart their electrical grid, piece by piece, county by county.
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. . . we’ll be focusing on one aspect of the February grid crash that’s often bandied about but rarely explained: that the Texas grid was mere minutes away from collapsing completely, and that it would have taken weeks or months to restore had it been able to slip away. Is that really possible? Can the power grid just “go away” completely and suddenly? The answer, sadly, is yes, but thankfully a lot of thought has been put into not only preventing it from happening but also how to restart everything if it does happen, by performing what’s known as a “Black Start.”
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Power generation is simple in theory, and we all learned the basics at one time or another — turn potential energy into kinetic energy to spin a magnet inside a big coil of wire. But the details are where the complexity lies. For example, in a coal power plant, milling the raw coal to the proper size to be used as fuel in the boilers takes power, as do the conveyors that feed the boilers, the actuators that control the valves, the sensors and control systems that regulate the speed of the turbines, and the switchgear that connects the generators to the grid. It takes power to make power . . .
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Aside from the equipment needed to fuel and control the power plant, there’s another piece of the black start puzzle that may come into play: excitation current. Most power plants use self-excited generators, meaning a small amount of the current they produce is used to power the field coils of the generator, creating the powerful magnetic field needed to generate electricity. Once a self-excited generator spins to a stop, there’s no current available to excite the field coils.
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Extended outages, however, may cause a rotor’s magnetic field to weaken enough that it will need a little help getting going. Black start procedures need to account for this eventuality by providing a means to “flash” the field windings with external power. The process for smaller generators is very similar, and it’s worth keeping in mind for anyone who stores a generator without actually taking it out and using it occasionally. Just keep in mind that for a power plant, it’s going to take much more than a hand drill to flash the windings.
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At the risk of oversimplifying a complex and far-flung series of events, for want of a set of tire chains, Texas came astonishingly close to losing their power not just for a couple of days, but for weeks or possibly months. It didn’t happen in this case, but only just barely and by several strokes of luck. We’ve no doubt that a lot of engineering skill and ingenuity went into getting the reluctant black start generators back online, too, so hats off to everyone who worked hard to avert the catastrophe. Hopefully, this will serve as a wake-up call . . .
https://hackaday.com/2021/07/15/blac...ets-restarted/
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