Inverter loss over nominal inv. power

[alex.reeser]

Question is about where the percentage value in the loss diagram for "inverter loss over nominal inv. power" come from? I've run a few simulations comparing actual production losses over a few DC/AC ratios and it does not appear that this particular loss factor scales properly eg. I remove strings to lower the DC/AC ratio and get 2% lower production but this particular loss only drops by about 0.5%. So would the inverter loss actually be simply the total POWER or TIME that the inverter is clipped and not ENERGY losses?

[André Mermoud]

The "Overload loss" is the not-produced energy, sum of the differences between the available Pmpp and the effective limited power accepted by the inverter according to Pnom when limited.

This value is computed at each simulation time step.

It is not proportional to the power ratio of course, as it is a non-linear effect: when diminishing the Array power, only a few days/hours will be affected by this threshold variation.

Please see the histogram in the tool "Show optimization" (System design dialog), and play with the power ratio for understanding the phenomenon.

[alex.reeser]

The "Overload loss" is the not-produced energy, sum of the differences between the available Pmpp and the effective limited power accepted by the inverter according to Pnom when limited.

This value is computed at each simulation time step.

It is not proportional to the power ratio of course, as it is a non-linear effect: when diminishing the Array power, only a few days/hours will be affected by this threshold variation.

Please see the histogram in the tool "Show optimization" (System design dialog), and play with the power ratio for understanding the phenomenon.

 

I think I am understanding. I think my confusion was just that when changing DC system size, I wasn't also accounting for the difference in this loss in the overall production as well. Thanks for the explanation