A dynamic model of a grid connected PV system based on outdoor measurment using Labview

One of the main task of the grid connected inverter is to derive the maximum available power from a photovoltaic plant, generally performed by a DC-DC converter, under variable irradiance and temperature. The purpose of this paper is to present a low complexity calculation procedure that allows to model the behavior of PV grid connected system at the DC side. The proposed procedure allows deriving dynamic locations of the maximum power point (MPP) of an entire PV plant under operation. Analytical approach combined with outdoor measurements is adopted in order to extract the main five parameters of the one diode I-V characteristic equation. Parameters extraction procedure and MPP derivation have been implemented in Labview and Matlab environment (co-simulation) where measured temperature and irradiance are taken as input variables. Finally, the dynamic model is evaluated under real PV system operation conditions and it has been found that it can be used as a monitoring system and detection of malfunction at the DC side.