Calculation: Maximum quantity of modules on a String & Irradiance test influence

[Jordann]

Hi PVSol forum & Team

Question please; how does the 'Irradiance (W/m2) of Maximum Open Circuit Voltage test' influence the calculated 'maximum quantity of modules on a string'?

For example, if test irradiance is set to 1,000W/m2 then you may have a max quantity of modules on a string of 23 modules. Though if if test irradiance is set to 1,250W/m2, then you may have a max quantity of modules on a string of 22 modules etc. A difference of 1 module etc in this quick example.

Question: what is the calculation formula that includes 'Irradiance (W/m2) of Maximum Open Circuit Voltage test'? 

Thank you in advance!

Yours

Jordan

[developer_mh]

Hi Jordan,

you can enter the limits for the voltage and current limit calculations in the options:

https://help.valentin-software.com/pvsol/en/pages/inverters/configuration-limits/

For the open circuit voltage we use the simple equation with the temperature coefficient alpha_U, see formula 11 here on this page:

https://help.valentin-software.com/pvsol/en/calculation/pv-modules/characteristic-curve-models/

Hope that helps, kind regards,

Martin