pvlib.ivtools.sdm.fit_cec_sam#
- pvlib.ivtools.sdm.fit_cec_sam(celltype, v_mp, i_mp, v_oc, i_sc, alpha_sc, beta_voc, gamma_pmp, cells_in_series, temp_ref=25)[source]#
Estimates parameters for the CEC single diode model (SDM) using the SAM SDK.
- Parameters
celltype (str) – Value is one of ‘monoSi’, ‘multiSi’, ‘polySi’, ‘cis’, ‘cigs’, ‘cdte’, ‘amorphous’
v_mp (float) – Voltage at maximum power point [V]
i_mp (float) – Current at maximum power point [A]
v_oc (float) – Open circuit voltage [V]
i_sc (float) – Short circuit current [A]
alpha_sc (float) – Temperature coefficient of short circuit current [A/C]
beta_voc (float) – Temperature coefficient of open circuit voltage [V/C]
gamma_pmp (float) – Temperature coefficient of power at maximum point point [%/C]
cells_in_series (int) – Number of cells in series
temp_ref (float, default 25) – Reference temperature condition [C]
- Returns
I_L_ref (float) – The light-generated current (or photocurrent) at reference conditions [A]
I_o_ref (float) – The dark or diode reverse saturation current at reference conditions [A]
R_s (float) – The series resistance at reference conditions, in ohms.
R_sh_ref (float) – The shunt resistance at reference conditions, in ohms.
a_ref (float) – The product of the usual diode ideality factor
n
(unitless), number of cells in seriesNs
, and cell thermal voltage at reference conditions [V]Adjust (float) – The adjustment to the temperature coefficient for short circuit current, in percent.
- Raises
ImportError – if NREL-PySAM is not installed.
RuntimeError – if parameter extraction is not successful.
Notes
The CEC model and estimation method are described in 1. Inputs
v_mp
,i_mp
,v_oc
andi_sc
are assumed to be from a single IV curve at constant irradiance and cell temperature. Irradiance is not explicitly used by the fitting procedure. The irradiance level at which the input IV curve is determined and the specified cell temperaturetemp_ref
are the reference conditions for the output parametersI_L_ref
,I_o_ref
,R_s
,R_sh_ref
,a_ref
andAdjust
.References
- 1
A. Dobos, “An Improved Coefficient Calculator for the California Energy Commission 6 Parameter Photovoltaic Module Model”, Journal of Solar Energy Engineering, vol 134, 2012. DOI: 10.1115/1.4005759