Unable to complete the power sharing

[MGLopez]

Hello,

Here is the description of the PV system:

Paramètres d'orientation
Type de champ:                     Plan incliné fixe
Inclinaison plan/azimut =       25°/18°

Compatibilité entre système et ombrages
Orientation du système compinclin/azim = 25° / 18°
      3 sous-champs                 PNom = 112 kWp,  surface de modules = 535 m²
      champs ombrages 3D       4 tables,      : , surface brute totale , . 739 m²

Paramètres du système
3 sous-champs définis
Sous-champ #1                      Shed 6
Modules PV:                            4 strings of 23 modules in series, 92  total
    Pnom = 405 Wc                  Pnom array = 37 kWc,  Area = 178 m²
Onduleurs (110 kWac)           4 entrées MPPT, Total 35 kW
Sous-champ #2                      Shed 7
Modules PV:                            4 strings of 23 modules in series, 92  total
    Pnom = 405 Wc                  Pnom array = 37 kWc,  Area = 178 m²
Onduleurs (110 kWac)           4 entrées MPPT, Total 38 kW
Sous-champ #3                      Shed 8
Modules PV:                            4 strings of 23 modules in series, 92  total
    Pnom = 405 Wc                  Pnom array = 37 kWc,  Area = 178 m²
Onduleurs (110 kWac)           4 entrées MPPT, Total 35 kW

I removed the shading scene description, suspecting it has no impact on the issue.

I try to use one single invertor Sunny Tripower STP 110-60-Core2, with 12 mppt to accept the 3 sub-arrays. I manage to assign only Shed 6 and Shed 7, so 8 mppt, and the Shed 9 is greyed so I cannot add it up to the configuration.

Checking Auto-equal Pnom or not does not change the fact that Shed 9 is out of reach.

Furthermore, I do not understand why the Pnom/MPPT figures do not match the actual hereabove given description, in the Power sharing dialog box. It shows the following :

- Shed 6 => 8.871 kW/MPPT, 8.06%Pnom,

- Shed 7 => 9.462 kW/MPPT, 8.60%Pnom

As both strings have the same amount of modules, one should read 9.315kW/MPPT

Thanks in advance for your help.

[Lazare Fesnien]

Hi,

The power isn't identical (35 and 38 kW) this explains the difference Pnom/MPPT.

To better help you we would need to analyze the complete project. 

You can send it to us at support@pvsyst.com