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gprado avatar image

SolarEdge AC coupling

I'm looking for a off-grid inverter that would handle a 20 kWh Tesla battery bank (2p2s 5.3kw modules) with a 8.8 kW solar system. I would like 10 kW peak power capability. Can I use a SolarEdge inverter and AC couple a Quattro inverter. I like the optimizer technology for dealing with partial shade issues. Any thoughts?

offgrid
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I am interested in this too. I already have a SolarEdge HDWave inverter with a 99.7% efficiency which I am interested in AC-Coupling. PowerControl via Frequency is supported; I am having trouble identifying the proper settings to achieve this however. See this document here, you may find helpful: https://www.solaredge.com/sites/default/files/application_note_power_control_configuration.pdf

I think I am actually very close to figuring this out; based on this section here we can infer the final value in the ESS Assistant, "Converter will disconnect when the frequency is higher than XX Hz", based on your country's electric code:

"The inverter de-rates power according to the defined graph, until the frequency reaches the trip value and the inverter disconnects (the trip point is preset per country therefore does not need to be defined as one of the two points)."


I am trying to find this information where I am located still unfortunately, but if you are able to identify this, then you have all you need. Enter this value for "Converter will disconnect when the frequency is higher than XX Hz"


The other two settings, This can be set in your inverter by the following:

To set P(f) and change the P or f values: 1. From the Power Control menu, select Active Power  P(f) 7. In the P(f) menu, enter Frequency (Hz) and P (% of nominal active power) values for P0 and P1.


P1 Will be your value for "Output will be reduced to minimum when frequency reached XX Hz" ... I think this should be set about 0.3 Hz below the last value for the disconnect frequency. As for the power factor, this is somewhat up to you, I am planning on testing a value of 5% here, which would be about 500W; the AC-Output demand is always 500W or above.


P0 will be your value for "the solar converter will start reducing it's out at XX Hz". I think this should be set to about 0.3Hz above your normal grid frequency (either 50.3Hz or 60.3Hz). And as for the Power Factor, I'm not entirely sure here weather this should be 100%, as in frequency needs to rise above this before being reduced, or to set this at about 90% so that it will already start to reduce at 0.3Hz above.


Once I have had a chance to test, I will let you know what I find.

Dear,

I experience a strange behaviour of the P(f) ramp on Solaredge side (operating in off grid and AC coupled). P(f) only works in one direction, power is reduced as a function of rising frequency. It then gets stuck at the lowest power limit. If frequency is reduced again, the Solaredge will not follow. Only when it reaches 50.0Hz and some time has passed a new cycle (only reduction, no gradual increase say from 51.2 Hz to 50.8Hz) will start. I use country parameter "Italy". @ee21Can you confirm this behaviour?


2 Answers
ee21 avatar image

I have tested and confirmed AC-Coupling works with my SolarEdge inverter. Steps to do so found here: https://community.victronenergy.com/questions/29888/need-some-help-defining-frequencies-in-ess-for-sol.html?childToView=30491#answer-30491

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Daniël Boekel (Victron Energy Staff) avatar image

Hi @gprado

from the manual:

To set P(f) and change the P or f values:

1. From the Power Control menu, select Active Power 

P(f) 7. In the P(f) menu, e

nter Frequency (Hz) and P (% of nominal active power) values for P0 and P1.

so if you set 100% 50,2Hz and 0% 53Hz and set your PV or ESS assistant in the Multi at the same values, this should work.


But please notice that I haven't worked with Solar Edge personally, and check with SE if these settings are withing the capability of the PV inverter.

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