Dear Pruthviraj Balekai,

welcome,

This question is interesting.

There are two types of models for any device including the solar cell; the behavioral model and the physically based model. The behavioral model describes the terminal performance of the device by looking  at and satisfying the terminal performance irrespective of the physics of the device. So, it is at the end effect some sort of curve fitting. This type of models has limited applicability as it can not describe the device performance in a wide range of operating conditions such as temperature and illumination intensity.  except with large number of parameters.

The more efficient and practical way is to develop physically based circuit models of the solar cells based on their physical operation. Since the solar cell is an illuminated diode, its equivalent circuit will be that of the diode added to it, the effect of the illumination by a photocurrent. So, from the operating principles the solar cell is a diode plus a photcurrent.  This model works well and describes the measured performance of the solar cell with sufficient accuracy and the smallest numbers of the model parameters if the the solar cells works as an ideal diode in the sense that the  dark current is limited by the recombination in the neutral regions of the p-n junction. One type of cells follow this model which is the single crystal Si solar cells as an example.

It is so that some solar cells can not be described fairly accurate with one diode, then one has to add an other diode in parallel. This is to account for the extra appreciable recombination current in space charge region of the diode of the solar cells.

In the heterojunction solar cells, there will be also two dominant recombination regions, the interface region and the neutral regions of the pn junction. The recombination current in both regions has different ideality factors and thereby needs to diode for each one.

In case of pin solar cells, it is observed that the superposition of the dark current and the photocurrent is not valid which is apparent in crossing of the illuminated i-v to the dark curve at lower forward voltages. This is due to extra recombination in the i-region and thereby the collected photo current decreases with forward bias.

This type of solar cells is modeled by a diode and an extra loss current in parallel to the diode represented in the form of current source. Fore more information of such model of the pin solar cells please refer to the paper in the link:https://core.ac.uk/download/pdf/16200506.pdf

To take into consideration the homogeneous dark current distribution in the real large area solar cells the solar cell is represented by a distributed network of elementary diodes. To follow such distributed model please follow the paper in the link: https://www.researchgate.net/.../3062547_A_distributed_SPICE-model_of_a_solar_ce...

In case of that the metal semiconductor contacts not acting usually as ohmic contact one has to add a leaky diode in series with the series resistance of the solar cell:

To see such model please follow the link: https://www.researchgate.net/post/The_effect_of_MS_contacts_on_solar_cell_performance

In developing a model for a device it must describe the behavior of the device with acceptable accuracy while having the minimum number of model parameters. As the model gets more complicated, it will have more parameters and its computational load will increase. So, the increase of the model parameters must be handled with great care which means tha t they must be necessary.

Best wishes

Yes, there is 3-diode model

You might find additional PV models in the Modelica community. There are various PV libraries from different Research Institutes.

Example: https://github.com/raulrpearson/PVSystems

Yes, there is a three diode model available for PV modules but according to literature, the improvement in performance by using three diode model as compared to two diode model is sufficiently admissable only for large industrial panels.

Even in the case of double diode Vs Single diode, the improvement in accuracy is only at specific conditions, such as low irradiation etc.

In the end, it depends the application and extent of research you are conducting on the solar module for the selection of the apprpriate model

yes there is three diode model