Modeling a Multi-Junction PV Cell Based on Analytical Relations for Use in Associated Simulations

Photovoltaic cells are the basic elements in each PV system. In any condition, the behavior of a PV system can be analyzed by studying its constitutive PV cells. Single-junction PV cells are widely used in most of PV systems because of their low price. SJ cells have a disappointing defect and that is their low efficiency. Maximum efficiency for SJ cells is 15% in best conditions, which is not acceptable. So a new generation of PV cells with higher efficiencies have been produced and their technology is growing fast. New PV cells are multi-junction cells which have efficiencies about 50%. It is easy to predict that with more development in the related technology and lowering the price of MJ cells, they will have a significant share in PV systems. So it is necessary to implement a model for MJ PV cells to use in related simulations. In this paper after gathering basic analytical relations and equations of MJ cells, an appropriate model will be proposed.