A nonlinear least-squares optimization algorithm based on the Newton model modified with Levenberg parameter, is described for the extraction of the five illuminated solar cell parameters from the experimental data. An initialization routine based on the reduced nonlinear least-squares technique in which only two parameters have to be initialized, is introduced to overcome the difficulty in initializing the cell parameters. The program when incorporated into a microcomputer-based data acquisition software, allows an in-situ theoretical modelling of solar cells in laboratories. Results obtained for a commercial solar cell and a module are given.

Nonlinear Minimization Algorithm for Determining the Solar Cell Parameters with Microcomputers

Identification of PV solar cells and modules parameters using the genetic algorithms: Application to maximum power extraction

Analytical expressions are derived for the rapid extraction of solar cell single diode model parameters from experimental data. The resulting parameter values are shown to have less than 5% error for most solar cells

Accurate analytical method for the extraction of solar cell model parameters

A comparative study of three methods for extracting solar cell parameters of the single-diode lumped-circuit model is presented. The methods compared are the curve-fitting method, an iterative 5-point method and a recently proposed analytical 5-point method. Parameter values were extracted using these three methods from experimental characteristics collected from two silicon cells over a range of illuminations and temperatures. The results show that the curve-fitting method can often give erroneous parameter values and the reasons for the errors are discussed. The 5-point methods are found to be reliable and accurate in situations where the model is a good approximation of cell performance. The analytical 5-point method, however, has the added advantage of simplicity. It is also found that for the cell measured, the single diode model is valid at illuminations above one-half AM1 but gives non-physical parameter values at lower illumination.

M. Abdelkrim

Papers

A practical method of analysis of the current-voltage characteristics of solar cells