Good morning,

 

I am considering the following configuration of 5 strings of 18 modules each with the 20KTL Huawei inverter and AC-300M/60S modules:

 

That is, not the typical configuration of two identical strings per MPP, as the current would be too high:

 

I understand that the first configuration is possible, but I'm not sure how the connection would be done in the "real world". Would it be a string per MPP input entrance, leaving the sixth unused? How would the inverter know I'm not following the second configuration, which is not allowed?

 

Thanks in advance, kind regards,

 

Ricardo

UPDATE:

I contacted Huawei and they confirmed that the proposed configuration will not work.

 

Is there any other way that the mentioned modules and inverter can be configured together?

Hi Ricardo,

how it would be done in the real world is a very good question. I guess you should ask the Huawei people I quickly scanned the user and installation manual for the SUN2000-20 KTL but I did not find any settings that would tell the inverter how to handle the MPP trackers and DC inputs.

The ability to operate the MPP trackers together is something that the manufacturers enter into our database. So perhaps it would be best to ask the technical support of Huawei. support@huawei.com

Kind regards,

Martin

ah, you were faster. So the database entry is wrong. I will inform our database team.

Thanks Martin,

So just to confirm, there is no way to configure 90 AC-300M/60S modules with the 20KTL inverter, then? This messes my planning a bit, as I took for granted that PV SOL was offering a feasible solution...

Kind regards,

Ricardo

Hi Ricardo,

I mean you could still use the configuration as in your version 2. The maximum current is only exceeded by 0.54 A, I guess that the energy losses due to current clipping will not be too high.

I just simulated it with one-minute values for Berlin, and the current clipping (down-regulation) is really insignificant.

Kind regards,

Martin

Thanks, I'll try that.