pvlib.pvsystem.sapm#
- pvlib.pvsystem.sapm(effective_irradiance, temp_cell, module)[source]#
The Sandia PV Array Performance Model (SAPM) generates 5 points on a PV module’s I-V curve (Voc, Isc, Ix, Ixx, Vmp/Imp) according to SAND2004-3535. Assumes a reference cell temperature of 25 C.
- Parameters:
effective_irradiance (numeric) – Irradiance reaching the module’s cells, after reflections and adjustment for spectrum. [W/m2]
temp_cell (numeric) – Cell temperature [C].
module (dict-like) – A dict or Series defining the SAPM parameters. See the notes section for more details.
- Returns:
A DataFrame with the columns –
i_sc : Short-circuit current (A)
i_mp : Current at the maximum-power point (A)
v_oc : Open-circuit voltage (V)
v_mp : Voltage at maximum-power point (V)
p_mp : Power at maximum-power point (W)
i_x : Current at module V = 0.5Voc, defines 4th point on I-V curve for modeling curve shape
i_xx : Current at module V = 0.5(Voc+Vmp), defines 5th point on I-V curve for modeling curve shape
Notes
The SAPM parameters which are required in
module
are listed in the following table.The Sandia module database contains parameter values for a limited set of modules. The CEC module database does not contain these parameters. Both databases can be accessed using
retrieve_sam()
.Key
Description
A0-A4
The airmass coefficients used in calculating effective irradiance
B0-B5
The angle of incidence coefficients used in calculating effective irradiance
C0-C7
The empirically determined coefficients relating Imp, Vmp, Ix, and Ixx to effective irradiance
Isco
Short circuit current at reference condition (amps)
Impo
Maximum power current at reference condition (amps)
Voco
Open circuit voltage at reference condition (amps)
Vmpo
Maximum power voltage at reference condition (amps)
Aisc
Short circuit current temperature coefficient at reference condition (1/C)
Aimp
Maximum power current temperature coefficient at reference condition (1/C)
Bvoco
Open circuit voltage temperature coefficient at reference condition (V/C)
Mbvoc
Coefficient providing the irradiance dependence for the BetaVoc temperature coefficient at reference irradiance (V/C)
Bvmpo
Maximum power voltage temperature coefficient at reference condition
Mbvmp
Coefficient providing the irradiance dependence for the BetaVmp temperature coefficient at reference irradiance (V/C)
N
Empirically determined “diode factor” (dimensionless)
Cells_in_Series
Number of cells in series in a module’s cell string(s)
IXO
Ix at reference conditions
IXXO
Ixx at reference conditions
FD
Fraction of diffuse irradiance used by module
References