Optimal bypass diode configuration for PV arrays under shading influence

Under partial shading conditions caused by the unevenly radiation and other ambient environmental conditions the operation of solar cells is influenced. Depending on the degree of shading, the phenomenon causes the decrease of solar cells output power. In the present paper two bypass diode configurations are compared, PV module with a bypass diode across each cell and with a bypass diode across each group cell, which are the most studied in the scientific literature. A PV module with analyzed bypass configurations was implemented in PSpice. This paper analyses the effects of bypass diode configurations on photovoltaic systems operation under various shaded degrees. The simulation results reveal that both solutions can limit the effects of this shading phenomenon and thus enhance the operational performance of photovoltaic (PV) systems. Further, the analysis of simulation results for I-V and P-V characteristic curves highlight the advantages and disadvantages of each type of bypass diode configuration, and also their use in practice.