Huawei optimizer strings configuration - ERRORS and CRASH

[R. Polášek]

Hello,

While putting together a Huawei based system I encountered a series of errors related to the use of Huawei optimizers and am currently unable to progress past the system configuration. Below, I will try to explain the process and the individual errors I am encountering.

The system is composed of 1 inverter (the Huawei SUN2000-40KTL-M3-400V) split into 4 separate sub-arrays, each consisting of 1 MPPT with 2 strings.

Along with the Huawei inverter, Huawei optimizers were selected and distributed across all PV modules, leading to compulsory string configuration which was set up as seen below:

 

This was not immediately possible and I had to manualy close this window and quickly edit the total module number by a few modules more and then back in order to get rid of automated errors claiming the strings were not distributed correctly (unfortunately I was not able to replicate this bug in my latest session).

The problem however remains and while the inverter input distributions claims the string / MPPTs are distribute dcorrectly, there is error at the bottom preventing me from continuing further:

Following the blue text instructions just leads to the reset of the atribution and after repeating the process I arrive at the exact same error of "2 strings strings doubled in the inverter list". If I press okay and then confirm that I want to keep the changes even with the error present, I get brought back to the system window and something even stranger happens, the total AC power just randomly changes from the expected 40kW of the 40kW inverter to seemingly random value up to 40 (30kW AC in the example below):

This persists until the total number of pv modules in any sub-array is changed but this action resets the string configuration of optimizers, requiring me to go through the process again and eventually just leading to the same result (this time the nominal AC power was changed from 40 to 34,7 kW, next time it was 30,4 kW).

If I decide to close the system definition menu using the OK button even though the following error is displayed I am not able to proceed further.

Furthermore, if I decide to save the project at this point, the whole program crashes. I have sent the bug report via email.


Thank you in advance for any replies or answers to this post,
I hope this can lead to quick solution of these problems.

R. P.

[Robin Vincent]

Dear R. Polášek,

Thank you for bringing up this issue. We are aware that the multi-string attribution on a single MPPT with Huawei inverters/optimizers currently has some limitations.

If you're working with just one subarray, this shouldn't pose any problems. However, given your situation with multiple subarrays, unfortunately, it will not function as expected.

We are actively working on a fix, which will be implemented in PVsyst V8. Until then, you won't be able to simulate your project as it is currently configured.

As a temporary solution, we recommend ensuring that each inverter is connected to only one subarray. This should allow you to proceed with your simulation in the meantime.