Modeling of single phase inverter of photovoltaic system using Hammerstein–Wiener nonlinear system identification

This paper proposes a new method to modeling a power inverter of grid-connected photovoltaic system by using a nonlinear system identification technique based on the Hammerstein–Weiner model. In this method, the system is considered as a black box of which it is not necessary to know structures and parameters inside. A nonlinear system identification, which is composed of nonlinear blocks and linear blocks, has been processed and synthesized yielding the modeling from only measured inputs and outputs of the system. An inverter of a grid-connected photovoltaic system has been tested and its model determined. Results on modeling the voltage, current and power waveforms have accuracies of 98.13%, 95.02% and 91.05% respectively. The mathematical model being the representation of the system can be analyzed and provide characteristics on controllability, stability, power quality, power flow.