Inverter Losses

[Shy A]

Hi,

I am simulating a 440kWp system with a Solectria central inverter.

The inverter's efficiency is 97.9%/97.5%, and there is shading on the roof.

I am using the module layout to accurately calculate the shading loss.

The inverter is loaded at 1.47 DC/AC - so there is power clipping.

My question relates to the various efficiency losses of the inverter, as can be seen in the image attached:

-1.6% Inverter Loss during operation (efficiency) - (this is higher than the max efficiency...)

-0.5% Inverter Loss over nominal inv. power - (this is the power clipping)

0.0% Inverter Loss due to power threshold

0.0% Inverter Loss over nominal inv. voltage

-1.4% Inverter Loss due to voltage threshold (is this due to the shading preventing the inverter from reaching operating/MPP voltage?)

My question is: why is the efficiency at 1.6%, where it should be 2-3%? does it have a relationship with the voltage threshold efficiency loss?

 

 

Thank you!

Shy

[André Mermoud]

Hi Shy

There were indeed an error in the simulation when using the "Module Layout" option, up to the version 6.19, affecting the inverter efficiency (in fact the EArray value).

- Does this strange result still occur if you update to the latest version ?

If yes, please send me your whole project.

Yes, the Il_VmppMin may result of voltage drop due to shadings in the Module Layout part.

[Shy A]

Thanks Andre, indeed, V.22 fixed this issue, see below.