pvl_calcparams_desoto

Calculates five parameters to compute IV curves using the De Soto model [1].

Contents

Syntax

Description

Calculates IL, I0, Rs, Rsh, and a according to the model in [1]. The results can be used in the single diode equation to determine IV curves at irradiance S and cell temperature Tcell.

Inputs

Outputs

Notes

If the reference parameters in the ModuleParameters struct are read from a database (e.g. the SAM module database), it is important to use the same values for EgRef and dEgdT that were used to generate the reference parameters, regardless of the actual bandgap characteristics of the semiconductor. For example, in the case of the System Advisor Model library, created as described in [2], EgRef and dEgdT for all modules were 1.121 eV and -0.0002677 eV/K, respectively.

Example 1

IV curves at a range of irradiance values

Ee = [200 400 600 800 1000 1100]; % effective irradiance Levels (W/m^2) for parameter sets
Tcell = 45; %deg C

load('CECModuleDatabaseSAM2014.1.14.mat')
% Yingli Energy (China) YL295P-35b  # 9764
Module = CECModuleDB(9764);
% Bandgap and Bandgap temperature dependence from [2]
EgRef = 1.121; %Reference band gap.
C = -0.0002677;  %Band gap dependence on temperature.

[IL, I0, Rs, Rsh, a] = pvl_calcparams_desoto(Ee, Tcell, Module.alpha_sc, Module, EgRef, C);
NumPoints = 1000;
[IVResult] = pvl_singlediode(IL, I0, Rs, Rsh, a, NumPoints);

figure
for i=1:6
plot(IVResult.V(i,:),IVResult.I(i,:))
hold on
scatter(IVResult.Vmp(i),IVResult.Imp(i),'filled')
text(2,IVResult.Isc(i)+0.3,[num2str(Ee(i)) ' W/m^2'])
end
xlabel('Voltage (V)')
ylabel('Current (A)')
title('Example IV Curve from De Soto Single Diode Model','FontSize',14)
ylim([0 11])

Example 2

IV curves at a range of cell temperature values and at AM = 3

S = 1000; %broadband irradiance Levels for parameter sets
Tcell = [30 40 50 60 70 80]; %deg C
AMa = 3; % Absolute (pressure corrected) airmass

% Bandgap and Bandgap temperature dependence from [2]
EgRef = 1.121; %Reference band gap.
C = -0.0002677;  %Band gap dependence on temperature.

% Representative coefficients for estimating M/Mref for Poly-crystalline Si
% From Table A.1 in [1].
M = polyval([-0.000126 0.002816 -0.024459 0.086257 0.918093], AMa);

Ee = S.*M;

[IL, I0, Rs, Rsh, a] = pvl_calcparams_desoto(Ee, Tcell, Module.alpha_sc, Module, EgRef, C);
NumPoints = 1000;
[IVResult] = pvl_singlediode(IL, I0, Rs, Rsh, a, NumPoints);

figure
for i=1:6
plot(IVResult.V(i,:),IVResult.I(i,:))
hold on
scatter(IVResult.Vmp(i),IVResult.Imp(i),'filled')

end
xlabel('Voltage (V)')
ylabel('Current (A)')
title('IV Curves (Cell Temp from 30-80 deg C)','FontSize',14)
ylim([0 11])

References

See also

pvl_singlediode, pvl_SAMLibraryReader_CECModules

Copyright 2014 Sandia National Laboratories