Battery SOC when constrained

Hi, I had a look at the DiOrio paper , and still can't quite make sense of the simulated results for battery SOC in a PV-battery setup.

• To keep it simple, I exclude any grid usage - only PV and battery are allowed to interact
• My inputs under 'Battery Dispatch' are min SOC=10% and max SOC = 80%
• I had expected two possibilities for the modelled SOC data range:

1. 10-80% (ie the model would not scale constrained SOC, and effectively uses SOC values relative to nameplate capacity)
2. 0-100% (ie the model re-factors SOC to the constrained SOC range)

• However, when looking at the resulting SOC data range vs lifetime hourly data, its range is 10-~100%

How can I rationalise what's going on? Thanks! 

Hi Dirk,

We were not able to reproduce these results, but may not have used the same assumptions as yours.

Could you attach a .sam file that demonstrates these results?

Best regards,
Paul.

Hi Paul,
Sorry this took a while. 
I attach file JKM440 south.sam that shows the same outcome after running the standard simulation. 
Ie min SOC 10%, max S)C 80%, and the 'Lifetime hourly data' plot of Battery state of charge shows values in excess of 80% SOC (see attached XL).
(Export into grid and import from grid has been disabled on purpose.)
Kind regards
Dirk

Hi Dirk,

During grid outages, the battery dispatch overrides the minimum and maximum SOC. SAM assumes that it is more important to meet the critical load during outages than avoiding over- or under-charging the battery.

That assumption is based on relatively short grid outages of a few hours or perhaps days in a year.

Best regards,
Paul.

Many thanks for quickly clarifying this aspect Paul, makes sense. 
Kind regards - Dirk