Application of Extended Solar Cell Parameters to monitoring of IV characteristics

Detailed monitoring the reliability of photovoltaic (PV) modules often relies on analyzing the standard solar cell parameters over time. However, with current-voltage (I-V) sweeps available to determine the solar cell parameters, much information is lost if only four standard values (V
oc
, I
sc
, V
mpp
, I
mpp
) are used for further analysis. In this paper we present extended solar cell parameters which allow a compact and standardized description of a complete I-V characteristic. Furthermore, the extended solar cell parameters are readily combined with the IEC60891 norm to obtain a temperature and irradiation dependent I-V model. We demonstrate that using this model also more subtle changes in the shape of the I-V characteristics can be effectively monitored.