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petajoule asked

Sub-50Hz compensation in PV-Inverter support

PV Inverter support uses frequency shifting to steer PV Inverter output on the AC branch.

This works very nice and reliable with Fronius inverters in our nstallations.

However, this frequency shift works only in the 50Hz+ range, there is never a compensation below 50Hz:

Now all devices in the microgrid that take these 50Hz as source for their internal clocks (actually quite a few do - e.g. microwave oven clocks) start to get ahead of time noticeably within a month.

Wouldn't it be possible to implement a sub-50Hz compensation in the nighttime to counter the effect that accumulates over daytime?

As soon as e.g. the Fronius switches off for the night, there shouldn't be any adverse effects to lower network frequency to 49.5 or so.

According to our measurements, the clock skew can be as much as 0.8% per day - so I'd really appreciate if the assistant had some compensation measures built-in.


PS: If I choose "50Hz" as tag, it gets converted to "EasySolar All-in-one". ???

AC PV Couplingfrequency
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