Fronius generation data wiggles

Inverters Fronius
#1

I just commissioned a new system with a Fronius Primo inverter. I doesn’t have a solar meter. Instead, I’ve configured the inverter to upload at five minute intervals, and to send the log once an hour, as mentioned here.

This all works, I get the generation data just fine: Michi's New Cloud Attractor 6.660kW (Consumption data is uploaded by a Flukso.)

I have these wiggles in the generation data, which look like sampling artefacts. I’m wondering whether it’s possible to smooth out the graph?

Thanks,

Michii.

#2

There have been a few past attempts at explaining what is going on there - see
https://forum.pvoutput.org/search?q=fronius%20waves

(search ‘waves’ instead of ‘wiggles’)

The best explanation for the wiggles you are seeing is this Whirlpool post:
https://forums.whirlpool.net.au/thread/2634198?p=22#r428

The hourly ‘logdata’ push causes these wiggles (sampling, as you say, against the update interval inside the Fronius counters). The Logdata hourly push is there to recover any of the 5-minute samples that are missed - if your network connection is good and you don’t skip any of the 5-minute samples, you might be able to stop the hourly Logdata push and that may reduce or remove the wiggles.

You’re

#3

It’s a form of aliasing in the data used to generate the charts. One interval slightly under reports due to sample frequency not aligning with the reporting frequency, which is caught up by the following interval and the cycle repeats.

You’ll need to identify the cause of the aliasing. Is it the way PVO calculates interval data, or is it the way the data is presented to PVO?

#4

I wrote that post on WP long ago and still stand by that explanation. I saw the post here from Michi but by coincidence I happen to know him personally so contacted him directly to deal with this issue.

#5

Fronius does an artificial quality reduction :frowning:

#6

This issue has been addressed in https://forum.pvoutput.org/t/fronius-push-logdata-pac-options-ripple-fix/5489