SolarEdge - Optimizer derating max power

[76mtbeggs]

Hello,

For reference, I'm using V6.73.

While modelling with SolarEdge equipment, I'm finding that in the system definition tab, the array nominal power becomes derated, such that overload losses & production values appear to be inaccurate.

Example: screen shot attached

- Ex. 144x 365w module = 52.6kWp DC; Inverter = 43.2kW AC; DC/AC ratio = 1.22, yet...

- In the Array Design for SolarEdge architecture area, the Pnom ratio shows 1.13 and Overload loss shows 0.1%

- Note: 'Reference for sizing' box indicates that there's a Max. power of 678W/optimizer (acc. to best clear sky conditions). The behind the scenes calculation that arrives at the 678 W / optimizer seems to be causing the discrepancy.

Equipment spec'd:

- Hanwha Q Cells, Q.Peak L-G4.2 365 (2017): 144 pcs.

- SolarEdge P730-US: 2 modules in series, 1 module in parallel

- SolarEdge 14.4kW inverter; 8 optimizers in series / 9 strings in parallel

[André Mermoud]

With SolarEdge optimizers, the maximum power of a PV module is not defined as the Pnom (STC) nameplate value, as for any other sizing. It is indeed the maximum power delivered by this PV module over the whole year, for this array disposition, in clear sky conditions.

This was a reqirement of SolarEdge people when developing the SolarEdge devices in PVsyst.

[76mtbeggs]

Thank you.

Can you help me understand how the Max. Power per optimizer is calculated? For example, I see that changing the Field Thermal Loss Factor in Detailed Losses has an effect on inverter overload loss in the System configuration, but not on the Max. Power per optimizer.

I'd like to suggest the addition of a clickable question mark box next to the 'Reference for sizing' box in the Array Design for SolarEdge architecture that details how the the Max. power per optimizer is calculated.