pvlib.pvsystem.dc_ohms_from_percent

pvlib.pvsystem.dc_ohms_from_percent(vmp_ref, imp_ref, dc_ohmic_percent, modules_per_string=1, strings=1)

Calculate the equivalent resistance of the conductors from the percent ohmic loss of an array at reference conditions.

Parameters:

• vmp_ref (numeric) – Maximum power voltage of one module at reference conditions. [V]

• imp_ref (numeric) – Maximum power current of one module at reference conditions. [A]

• dc_ohmic_percent (numeric) – Array DC power loss as a percent of DC power loss at reference conditions. In percent, e.g. 1.5% loss is input as 1.5.

• modules_per_string (int, default 1) – Number of series-connected modules per string in the array.

• strings (int, default 1) – Number of parallel strings in the array.

Returns:

Rw (numeric) – Equivalent resistance. [ohm]

See also

pvlib.pvsystem.dc_ohmic_losses

Notes

Equivalent resistance is calculated as:

\[R_w = \left(\frac{L_{stc}}{100}\right) \times \left(\frac{ V_{array}}{I_{array}}\right)\]

\(R_w\) is the equivalent resistance in ohms. \(V_{array}\) is the array voltage, equal to vmp_ref times modules_per_string. \(I_{array}\) is the array current, equal to imp_ref times strings. \(L_{stc}\) is the input DC loss percent at reference conditions.