pvlib.pvsystem.v_from_i

pvlib.pvsystem.v_from_i(resistance_shunt, resistance_series, nNsVth, current, saturation_current, photocurrent)[source]

Device voltage at the given device current for the single diode model.

Uses the single diode model (SDM) as described in, e.g.,
Jain and Kapoor 2004 [1].
The solution is per Eq 3 of [1] except when resistance_shunt=numpy.inf,
in which case the explict solution for voltage is used.
Ideal device parameters are specified by resistance_shunt=np.inf and
resistance_series=0.
Inputs to this function can include scalars and pandas.Series, but it is
the caller’s responsibility to ensure that the arguments are all float64 and within the proper ranges.
Parameters:
resistance_shunt : numeric

Shunt resistance in ohms under desired IV curve conditions. Often abbreviated Rsh. 0 < resistance_shunt <= numpy.inf

resistance_series : numeric

Series resistance in ohms under desired IV curve conditions. Often abbreviated Rs. 0 <= resistance_series < numpy.inf

nNsVth : numeric

The product of three components. 1) The usual diode ideal factor (n), 2) the number of cells in series (Ns), and 3) the cell thermal voltage under the desired IV curve conditions (Vth). The thermal voltage of the cell (in volts) may be calculated as k*temp_cell/q, where k is Boltzmann’s constant (J/K), temp_cell is the temperature of the p-n junction in Kelvin, and q is the charge of an electron (coulombs). 0 < nNsVth

current : numeric

The current in amperes under desired IV curve conditions.

saturation_current : numeric

Diode saturation current in amperes under desired IV curve conditions. Often abbreviated I_0. 0 < saturation_current

photocurrent : numeric

Light-generated current (photocurrent) in amperes under desired IV curve conditions. Often abbreviated I_L. 0 <= photocurrent

Returns:
current : np.ndarray or scalar

References

[1] A. Jain, A. Kapoor, “Exact analytical solutions of the parameters of real solar cells using Lambert W-function”, Solar Energy Materials and Solar Cells, 81 (2004) 269-277.