question

daryl avatar image
daryl asked

Limit Charge Current with frequency shifting when off-grid behaving strangely

I have a 3-phase Multiplus II system with BYD batteries & AC coupled Solaredge with some DC coupled PV for black-start scenarios.

I use frequency shifting to control the Solaredge production. I can see the Solaredge ramp up/down according to the frequency changes.

I also use DVCC->Limit Charge Current to slowly charge the batteries each day and maximise the usage of the DC PV (it does not export). If I turn off the charge limiting, the Multiplus II's work hard, spin up their fans which can be heard inside the house so I want to keep it on.

If I drop the grid to the system, the Limit Charge Current setting seems to interfere with the frequency shifting to the point where the battery discharges rather than increase the AC coupled production to cover the load.

Limit charge current set to 50A, Victron setting the frequency to 50.9Hz:

1630365928751.png

Limit charge current turned off, Victron setting the frequency to 49.9Hz

1630365946987.pngDoes anyone have any ideas?

ESSDVCC
1630365928751.png (77.7 KiB)
1630365946987.png (83.7 KiB)
1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

daryl avatar image daryl commented ·

Anyone have any ideas? I feel like it's a software bug but of course maybe I'm missing some detail in one of the documents that tells me this is a feature.

0 Likes 0 ·
1 Answer
shaneyake avatar image
shaneyake answered ·
This does seem very strange, have you updated the GX and Multiplus to the latest firmware to see if it fixes it?
1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

daryl avatar image daryl commented ·
Thanks for the reminder about firmware. I did update the multiplus before posting, but it seems it didn't quite take it to the latest version. I did it again, also updated the ESS assistant and now that seems to have resolved the issue.
0 Likes 0 ·