pvlib.ivtools.sdm.fit_pvsyst_sandia#

pvlib.ivtools.sdm.fit_pvsyst_sandia(ivcurves, specs, const=None, maxiter=5, eps1=0.001)[source]#

Estimate parameters for the PVsyst module performance model.

Parameters:
  • ivcurves (dict) –

    iarray

    One array element for each IV curve. The jth element is itself an array of current for jth IV curve (same length as v[j]) [A]

    varray

    One array element for each IV curve. The jth element is itself an array of voltage for jth IV curve (same length as i[j]) [V]

    eearray

    effective irradiance for each IV curve, i.e., POA broadband irradiance adjusted by solar spectrum modifier [W / m^2]

    tcarray

    cell temperature for each IV curve [C]

    i_scarray

    short circuit current for each IV curve [A]

    v_ocarray

    open circuit voltage for each IV curve [V]

    i_mparray

    current at max power point for each IV curve [A]

    v_mparray

    voltage at max power point for each IV curve [V]

  • specs (dict) –

    cells_in_seriesint

    number of cells in series

    alpha_scfloat

    temperature coefficient of isc [A/C]

  • const (dict) –

    E0float

    effective irradiance at STC, default 1000 [W/m^2]

    T0float

    cell temperature at STC, default 25 [C]

    kfloat

    Boltzmann’s constant [J/K]

    qfloat

    elementary charge [Coulomb]

  • maxiter (int, default 5) – input that sets the maximum number of iterations for the parameter updating part of the algorithm.

  • eps1 (float, default 1e-3) – Tolerance for the IV curve fitting. The parameter updating stops when absolute values of the percent change in mean, max and standard deviation of Imp, Vmp and Pmp between iterations are all less than eps1, or when the number of iterations exceeds maxiter.

Returns:

dict

I_L_reffloat

light current at STC [A]

I_o_reffloat

dark current at STC [A]

EgReffloat

effective band gap at STC [eV]

R_sfloat

series resistance at STC [ohm]

R_sh_reffloat

shunt resistance at STC [ohm]

R_sh_0float

shunt resistance at zero irradiance [ohm]

R_sh_expfloat

exponential factor defining decrease in shunt resistance with increasing effective irradiance

gamma_reffloat

diode (ideality) factor at STC [unitless]

mu_gammafloat

temperature coefficient for diode (ideality) factor [1/K]

cells_in_seriesint

number of cells in series

ipharray

light current for each IV curve [A]

ioarray

dark current for each IV curve [A]

rsarray

series resistance for each IV curve [ohm]

rsharray

shunt resistance for each IV curve [ohm]

uarray

boolean for each IV curve indicating that the parameter values are deemed reasonable by the private function _filter_params

Notes

The PVsyst module performance model is described in [1], [2], and [3]. The fitting method is documented in [4], [5], and [6]. Ported from PVLib Matlab [7].

References