pvl_calcparams_CEC

Calculates five parameters for an IV curve using the CEC model.

Contents

Syntax

Description

Applies the temperature and irradiance corrections to calculate the five parameters for an IV curve according to the CEC model [1]. The results of this procedure may be used to determine the IV curve at effective irradiance = S, cell temperature = Tcell.

Inputs

Outputs

Notes

In the case of the CEC model and the parameters in the System Advisor Model library, created as described in [3], EgRef and dEgdT for all modules are 1.121 and -0.0002677, 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);

[IL, I0, Rs, Rsh, a] = pvl_calcparams_CEC(Ee, Tcell, Module);
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 CEC 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

% Representative coefficients for estimating M/Mref for Poly-crystalline Si
% From Eq. 9.23 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_CEC(Ee, Tcell, Module);
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:

[1] P. Gilman, SAM Photovoltaic Model Technical Reference, National Renewable Energy Laboratory (NREL) Technical Report NREL/TP-6A20-64102, May 2015.

[2] A. Dobos, "An Improved Coefficient Calculator for the California Energy Commission 6 Parameter Photovoltaic Module Model", Journal of Solar Energy Engineering, vol 134, 2012.

See also

pvl_singlediode, pvl_SAMLibraryReader_CECModules

Copyright 2015 Sandia National Laboratories