Abstract-This paper focuses on a Matlab/SIMULINK model of a photovoltaic cell. This model is based on mathematical equations and is described through an equivalent circuit including a photocurrent source, a diode, a series resistor and a shunt resistor. The developed model allows the prediction of PV cell behaviour under different physical and environmental parameters. The model can also be used to extract the physical parameters for a given solar PV cell as a function of temperature and solar radiation. In addition, this study outlines the working principle of PV module as well as PV array. In order to validate the developed model, an experimental test bench was built and the obtained ...view middle of the document...
This free electron finds its path through an external circuit toward the positive layer resulting in an electric current from the positive layer to the negative one.
Fig.1.Photocurrent generation principle. Typically, a PV cell generates a voltage around 0.5 to 0.8 volts depending on the semiconductor and the built-up technology. This voltage is low enough as it cannot be of use. Therefore, to get benefit from this technology, tens of PV cells (involving 36 to 72 cells) are connected in series to form a PV module. These modules can be interconnected in series and/or parallel to form a PV panel. In case these modules are connected in series, their voltages are added with the same current. Nevertheless, when they are connected in parallel, their currents are added while the voltage is the same. Three major families of PV cells are monocrystalline technology, polycrystalline technology and thin film
INTERNATIONAL JOURNAL of RENEWABLE ENERGY RESEARCH Tarak Salmi et al., Vol.2, No.2, 2012 technologies. The monocrystalline and polycrystalline technologies are based on microelectronic manufacturing technology and their efficiency is in general between 10% and 15% for monocrystalline and between 9% and 12% for polycrystalline. For thin film cells, the efficiency is 10% for a-Si, 12% for CuInSe2 and 9% for CdTe [3]. Thus, the monocrystalline cell that has the highest efficiency is the focus of this paper. This paper carried out a Matlab/SIMULINK model of monocrystalline PV cell that made possible the prediction of the PV cell behaviour under different varying parameters such as solar radiation, ambient temperature, series resistor, shunt resistor, diode saturation current, etc. The focus of this paper is on solar cell modelling which is discussed in section two. Section three presents the effects of the variation of the solar radiation. In section four, the influence of temperature on the PV cell outputs are investigated. The effects of the series resistance have been presented in section five. Section six focuses on the effects of the shunt resistance. In section seven, the effects of the diode reverse saturation current are studied. The model features and its experimental validation are discussed in sections eight through ten. While conclusions and future works are presented in section eleven. 2. PV cell model Fig. 4.I-V curves and P-V curves for a given PV cell 3. Effects of Solar Radiation Variation and Rsh, the I-V and P-V curves are generated as shown in Fig.4.
Fig. 3. PV cell Matlab/SIMULINK model.
The equivalent circuit of a PV cell is shown in Fig. 2. It includes a current source, a diode, a series resistance and a shunt resistance [4, 5].
The above model includes two subsystems: one that calculates the PV cell photocurrent which depends on the radiation and the temperature according to equation (2) [3].
I ph I sc K i T 298 1000
(2)
where Ki=0.0017 A/◦C is the cell's short circuit current...