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by bsder 411 days ago
> Harder mostly, See the frequency is set by huge rotating masses in the form of generators

I'm not saying you're wrong, but this isn't obviously correct to me.

Since solar going to a grid is completely dependent upon electronic DC->AC conversion, I would expect that it could follow a lot greater frequency deviation for a lot longer than a mechanical system that will literally rip itself apart on desync.
1 comments
eldaisfish 411 days ago
the person you replied to is mostly wrong.

The real reason that small scale solar PV is grid following (i.e. it depends on an external voltage and frequency reference) is that this ensures power line safety during a power outage. That's it.

An inverter can be programmed to start in the absence of an external reference and it can operate at a wide range of frequencies.

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ExoticPearTree 411 days ago
About 10 years ago I had a chance to work in the Utilities vertical for a power producer. I asked the same question: how is the frequency set and the answer was that the biggest power plant sets the frequency because they can produce a lot power and any other smaller generator would not be powerful enough to change the frequency.
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bsder 410 days ago
Sure, the smaller plant gets pulled into the larger plant's inertia.

However, DC-AC converters don't have an inherent inertia. They can follow almost any frequency and phase within reason. Certainly a DC-AC converter should be able to respond way faster than any frequency/phase changes that a mechanical system can generate.

In theory, they should be able to set themselves to be ever so slightly closer to ideal so that the amount of power they have to sink is limited but are still exerting a very slight force to bring the grid back into compliance rather than continuing to add load which propagates the collapse.

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