Implementation of 3D lookup tables in PLECS for modeling photovoltaic modules

Creating a meaningful photovoltaic (PV) model for circuit simulation software is a task that designers of PV interfacing converters usually deal with during the early stage of a project. The electrical behavior of a PV module can be represented by a 3D lookup table storing values of the PV current for different values of voltage, solar irradiation and temperature. This paper proposes a rounded guideline to produce such 3D lookup tables. Three fundamental aspects are covered: estimate of the five unknown modeling parameters of the single-diode equivalent circuit uniquely from datasheet values; analysis of solar irradiation and temperature effects on the PV current; and calculation of the 3D lookup table. A PV modeling case study for a polycrystalline PV module is presented. It is shown how the framework outlined in this paper outputs more accurate results than the methodology used in an application example issued by PLECS.