Abstract:

By experiments, it was found that each solar cell in the photovoltaic (PV) module generally had different temperatures  whose value could be well approximated by normal distribution. The abnormal behavior in the I-U curve was also observed. This study showed that it was reasonable to employ the relative standard error of the temperature as that of the electrical parameters of PV modules. Based on this assumption,  cell parameters were randomly generated, and then the abnormal behavior in the I-U curve was well simulated by the series connection of these cells. The same method was applied to  a virtual 5 kW PV array, and the power loss was estimated around 200W due only  to the electrical parameter fluctuation. The results revealed that the consistency of the electrical parameters of the PV modules should be stressed in the construction of a large PV array.

Key words: solar cell, temperature distribution, quality fluctuation