This work investigated, using a 3-D modelling, the influence of electrons losses on the performance of a polycrystalline silicon PV cell.
The electrons transport equations have been solved by taking into account the rate of electrons lost at the junction (Sf0) to find the expression of the electrons’ density which allowed to derive the expressions of the electrical parameters (Jph, Vph, P) then those of the performance parameters (η, Rsh) of the PV cell grain. Then we analyzed, from a numerical simulation, the effects of the rate of electrons lost at the junction (Sf0) on the performance parameters (η, Rsh) found from the curves of output power (PT) -diffusion velocity (Sfj).
Results of simulation showed that, in open circuit, there is a leakage current at the junction of the PV cell grain whose density increases from 0 mA.cm-2 à 58.80 mA.cm-2 resulting in a drastic drop in the shunt resistance from infinity to 4.273 Ω.cm 2 and a drop in the conversion efficiency of 34.376%. Considering the manufacturers’ standards, 20% drop in efficiency, so for Sf0 = 1,790×104 cm.s-1 the PV cell is degraded.
This paper investigated, using 1-D analysis, the effect of low energy electrons emitted from Promethium – 147 (Pm-147) on the performance of a silicon PV cell. The Pm-147 source is chosen due to the penetration depth of beta particles with the average kinetic energy of 62.5 KeV emitted from Pm-147, because at this depth the are able to generate charge carriers right down to the base. The continuity equation of excess minority carrier is solved respectively in the emitter for excess holes and in the base for excess electrons. The analytical expression of the density of electrons and holes for each part of the solar cell is derived and, in turn, the electrical parameters (Jsc, Voc, FF, η) of the PV cell are found. The influence of radiation flux on short-circuit current density (Jsc), Open circuit voltage (Voc), fill factor (FF) and conversion efficiency (η) are discussed. if we vary the flux of incident particles up to the value of 3.1010 cm-2, we achieve a relative increase in the PV Cell conversion efficiency of the order of 0.2743 %.
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