Solar Cell Model Parameters Research Articles

The effect of the front contact sheet resistance on solar cell performance

The transparent top contact layer of a solar cell is a distributed resistance that cannot be easily represented mathematically. We have used a finite element model to calculate the current distribution in this transparent layer. The calculation gives the voltage drop along the layer as well as the resulting reduction in the current generated in the active layer of the solar cell. IV curves generated by the model are used to investigate various methods of experimentally determining series resistance. It is found that the suns- V oc method is the most accurate. A fit of the finite element model to experimental IV data from an organic solar cell is used as an example of obtaining solar cell model parameters.

EXTRACTION OF ILLUMINATED SOLAR CELL AND SCHOTTKY DIODE PARAMETERS USING A GENETIC ALGORITHM

Details concerning the implementation of a versatile genetic algorithm are presented. Solar cell and Schottky diode model parameters are extracted based on the fitness of experimental data to theoretical curves simulated in the framework of certain physical processes and the use of this genetic algorithm. The method is shown to be a reliable alternative to conventional numerical techniques in fitting experimental data to model calculations and the subsequent determination of model related parameters. It is demonstrated, through two examples in particular, that some of the drawbacks associated with the conventional methods can be circumvented if a genetic algorithm is used instead. For instance, a good initial guess is not a critical requirement for convergence and an initial broad range for each of the fitting parameters is enough to achieve reasonably good fits.

New method to extract the model parameters of solar cells from the explicit analytic solutions of their illuminated characteristics

Abstract We present a new method to extract the intrinsic and extrinsic model parameters of illuminated solar cells containing parasitic series resistance and shunt conductance. The method is based on calculating the Co-content function (CC) from the exact explicit analytical solutions of the illuminated current–voltage (I–V) characteristics. The resulting CC is expressed as a purely algebraic function of current and voltage from whose coefficients the intrinsic and extrinsic model parameters are then readily determined by bidimensional fitting. The procedure is illustrated by applying it to experimental and synthetic I–V characteristics and an analysis of the errors is presented.

The effect of electron damage on silicon solar cells coated with diamond-like carbon films

The unique properties of the diamond-like carbon (a:DLC), such as high mechanical hardness and abrasive resistance, optical transparency in the visible and IR spectral regions and high thermal conductivity, provide this material with advantages over other types of protecting materials for solar cells. Furthermore, the a:DLC films are inert to corrosive gases and other corrosive agents. Resistance to radiation damage of the a:DLC films deposited on solar cells is very important for space application. In the study we investigate the effect of electron damage on silicon solar cells coated with a:DLC films. We measure the I – V characteristic and the spectral response and calculate the values of the seven parameters of the double exponential solar cell model (usually not investigated) as a function of electron fluence irradiation. In addition we obtain also the usual external parameters Isc, Voc, Im, Vm, FF, and efficiency) of the solar cells. We investigate solar cells with and without anti-reflecting coating coated with a:DLC films which were exposed to electron radiation. The main findings show that the solar cells with a:DLC films of thickness up to 500 nm degrade similarly to regular silicon cells exposed to electron irradiation. The degradation of the spectral response of the solar cell is mainly in the range of longer wavelengths and the irradiation affects the solar cell parameters (mainly the reverse saturation currents). Copyright © 2000 John Wiley & Sons, Ltd.

Analytical solution for solar cell model parameters from illuminated current-voltage characteristics

Abstract An improved analytical approach is introduced to calculate the solar cell parameters based on the lumped single exponential model. The main feature of this approach is that the diode junction ideality factor has been considered as an output characteristic dependent parameter under illuminated conditions. By using the experimental data of Charles, Abdelkrim, Muoy and Mialhe and Chan and Phang for five solar cells, the parameters are calculated and compared with the results of the analytical methods suggested either by Phang, Chan and Phillips or Kishore. The meaningless negative series resistance, caused by the assumption of a constant diode ideality factor along the entire current-voltage curve, can be avoided by the present analytical method.

Accurate analytical method for the extraction of solar cell model parameters

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

Solar power in space

The contribution of solar photovoltaics (PV׳s) in generation of electric power is continually increasing. PV cells are commonly modelled as circuits. Finding appropriate circuit model parameters of PV cells is crucial for performance evaluation, control, efficiency computations and maximum power point tracking of solar PV systems. The problem of finding circuit model parameters of solar PV cells is referred to as “PV cell model parameter estimation problem,” and is highly attracted by researchers. In this paper, the existing research works on PV cell model parameter estimation problem are classified into three categories and the research works of those categories are reviewed. Based on the conducted review, some recommendations for future research are provided.